Friday, December 31, 2021

The rise and fall of rationality in language

Fascinating language analysis from Scheffer et al. that illustrates over the past decades a marked shift in public interest from the collective to the individual, and from rationality toward emotion:  

Significance

The post-truth era has taken many by surprise. Here, we use massive language analysis to demonstrate that the rise of fact-free argumentation may perhaps be understood as part of a deeper change. After the year 1850, the use of sentiment-laden words in Google Books declined systematically, while the use of words associated with fact-based argumentation rose steadily. This pattern reversed in the 1980s, and this change accelerated around 2007, when across languages, the frequency of fact-related words dropped while emotion-laden language surged, a trend paralleled by a shift from collectivistic to individualistic language.
Abstract
The surge of post-truth political argumentation suggests that we are living in a special historical period when it comes to the balance between emotion and reasoning. To explore if this is indeed the case, we analyze language in millions of books covering the period from 1850 to 2019 represented in Google nGram data. We show that the use of words associated with rationality, such as “determine” and “conclusion,” rose systematically after 1850, while words related to human experience such as “feel” and “believe” declined. This pattern reversed over the past decades, paralleled by a shift from a collectivistic to an individualistic focus as reflected, among other things, by the ratio of singular to plural pronouns such as “I”/”we” and “he”/”they.” Interpreting this synchronous sea change in book language remains challenging. However, as we show, the nature of this reversal occurs in fiction as well as nonfiction. Moreover, the pattern of change in the ratio between sentiment and rationality flag words since 1850 also occurs in New York Times articles, suggesting that it is not an artifact of the book corpora we analyzed. Finally, we show that word trends in books parallel trends in corresponding Google search terms, supporting the idea that changes in book language do in part reflect changes in interest. All in all, our results suggest that over the past decades, there has been a marked shift in public interest from the collective to the individual, and from rationality toward emotion.

Wednesday, December 29, 2021

Senolytic therapies for healthy longevity

An article on increasing longevity by getting rid of senescent cells (cells that have stopped dividing and generate products that accelerate aging) has been languishing in my queue of potential posts for over a year, and I want to finally give it a mention. (This continues the thread of MindBlog posts over the years that have dealt with anti-aging supplements. You can enter 'resveratrol' in the search box in the right column of this blog to get a sample. I've reported on several self experiments, none of which ended all that well. A 2008 post on my experimenting with a resveratrol supplement generated a comment thread that has continued for many years.)

Here is the abstract of the review article by Jan M. van Deursen in Science Magazine:

The estimated “natural” life span of humans is ∼30 years, but improvements in working conditions, housing, sanitation, and medicine have extended this to ∼80 years in most developed countries. However, much of the population now experiences aging-associated tissue deterioration. Healthy aging is limited by a lack of natural selection, which favors genetic programs that confer fitness early in life to maximize reproductive output. There is no selection for whether these alterations have detrimental effects later in life. One such program is cellular senescence, whereby cells become unable to divide. Cellular senescence enhances reproductive success by blocking cancer cell proliferation, but it decreases the health of the old by littering tissues with dysfunctional senescent cells (SNCs). In mice, the selective elimination of SNCs (senolysis) extends median life span and prevents or attenuates age-associated diseases (1, 2). This has inspired the development of targeted senolytic drugs to eliminate the SNCs that drive age-associated disease in humans.
A few clips from the article:
Much of our current knowledge about the properties of SNCs is based on experiments in cultured cells, largely because SNCs in tissues and organs are difficult to identify and collect. One key characteristic of SNCs is that they are in a state of permanent cell-cycle arrest....SNCs produce a bioactive “secretome,” referred to as the senescence-associated secretory phenotype (SASP). This can disrupt normal tissue architecture and function through diverse mechanisms, including recruitment of inflammatory immune cells, remodeling of the extracellular matrix, induction of fibrosis, and inhibition of stem cell function . Paradoxically, although cellular senescence has evolved as a tumor protective program, the SASP can include factors that stimulate neoplastic cell growth, tumor angiogenesis, and metastasis, thereby promoting the development of late-life cancers. Indeed, elimination of SNCs with aging attenuates tumor formation in mice, raising the possibility that senolysis might be an effective strategy to treat cancer.
The article proceeds to outline several different efforts to identify senolytic drug targets. It notes that:
...natural products with anticancer properties, such as quercetin and fisetin, and quercetin in combination with the pan-tyrosine kinase inhibitor dasatinib, have been reported to eliminate SNCs in vitro and in mice [M. Xu et al., Nat. Med. 24, 1246 (2018); M. J. Yousefzadeh et al., EBioMedicine 36, 18 (2018)]. Although quercetin, fisetin, and dasatinib are often referred to as senolytics, it should be noted that they each act on a myriad of pathways and mechanisms implicated in diverse biological processes. This makes it difficult to decipher how these drugs eliminate or otherwise impact SNCs and to attribute any therapeutic or detrimental effects they may have in clinical trials to senolysis.
A brief google search on these flavinoid antioxidant compounds (found in fruits and vegetables...strawberries, watercress, cilantro, etc.) finds a large number of "Life Extension" dietary supplements featuring them. There is no data on their effects on senolysis or life span in humans.

Monday, December 27, 2021

MindBlog gets an extreme comment on Covid

I've debated on whether it would be better to ignore (and not amplify by passing on) an extreme comment of a sort MindBlog almost never receives. It is sent as a response to, but does not actually comment on, last Wednesday's post on the David Brooks article "What Happened to American Conservatism."  Although I am in complete disagreement with the comment's content, I've decided to pass it on because  it is an instructive example of the quality, style, stance and arguments of a fraction of America's population large enough to guarantee the continued generation of Covid variants that will maintain Covid as a chronic disease for the foreseeable future.  Here's the comment:
Re the "the human condition"... The TRUE human condition or world we live in is about 2 pink elephants in the room and has never been on clearer display than with the deliberate global Covid Scam atrocity — check out “The 2 Married Pink Elephants In The Historical Room –The Holocaustal Covid-19 Coronavirus Madness: A Sociological Perspective & Historical Assessment Of The Covid “Phenomenon”” at w w w d o t CovidTruthBeKnown d o t c o m 
“[…] when you do things to people against their will and force them it destroys their spirit, it destroys the integrity of their body. […]. Being an adult is meaningless if you cannot even protect the integrity of your own body.” -- Jennifer Daniels, MD, MBA, Holistic Doctor 
If your employer (even educational or federal employers) wants you to take a Covid vaccine give him/her one of these form letters of exemption found at w w w d o t lc d o t o r g/exempt 
By the way, with the letters of "omicron" an alleged Covid variant you can spell "moronic"...
And further speaking of stupid herd people not getting the glaringly obvious truth/ie not getting the constant onslaught of BIG lies of the official authorities, the world we live in and what the human condition is really is encapsulated in the following reality... 
"2 weeks to flatten the curve has turned into...3 shots to feed your family!" --- Unknown

Saturday, December 25, 2021

A musical offering.

For this day that was central in my Protestant Christian Texas childhood: a performance by the Netherlands Bach Society of the Gloria in Excelsis Deo from Bach's  Christmas Cantata BVW 191 first performed in Leipzig ~1742. There is joy in this music that transcends it’s religious origins. 

Wednesday, December 22, 2021

What Happened to American Conservatism?

I want to strongly recommed that you read David Brooks' article on conservatism in the January/February 2022 issue of The Atlantic. I read slowly though it three times, think it makes a compelling summary of our current political quandry, and wish that it offered more insight into possible ways out of our current predicament as we watch what seems to be an unstopable slippage back to pre-Enlightenment mentalities. Just a few clips of text towards the end of the piece:
...perhaps the biggest reason for conservatism’s decay into Trumpism was spiritual. The British and American strains of conservatism were built on a foundation of national confidence...By 2016, that confidence was in tatters. Communities were falling apart, families were breaking up, America was fragmenting. Whole regions had been left behind, and many elite institutions had shifted sharply left and driven conservatives from their ranks. Social media had instigated a brutal war of all against all, social trust was cratering, and the leadership class was growing more isolated, imperious, and condescending. “Morning in America” had given way to “American carnage” and a sense of perpetual threat.
...a pessimistic shadow conservatism has always lurked in the darkness, haunting the more optimistic, confident one. The message this shadow conservatism conveys is the one that Trump successfully embraced in 2016: Evil outsiders are coming to get us. But in at least one way, Trumpism is truly anti-conservative. Both Burkean conservatism and Lockean liberalism were trying to find ways to gentle the human condition, to help society settle differences without resort to authoritarianism and violence. Trumpism is pre-Enlightenment. Trumpian authoritarianism doesn’t renounce holy war; it embraces holy war, assumes it is permanent, in fact seeks to make it so. In the Trumpian world, disputes are settled by raw power and intimidation. The Trumpian epistemology is to be anti-epistemology, to call into question the whole idea of truth, to utter whatever lie will help you get attention and power. Trumpism looks at the tender sentiments of sympathy as weakness. Might makes right.
...the populist and nationalist forces are rising. All of life is seen as an incessant class struggle between oligarchic elites and the common volk. History is a culture-war death match. Today’s mass-market, pre-Enlightenment authoritarianism is not grateful for the inherited order but sees menace pervading it: You’ve been cheated. The system is rigged against you. Good people are dupes. Conspiracists are trying to screw you. Expertise is bogus. Doom is just around the corner. I alone can save us.
Trumpian Republicanism plunders, degrades, and erodes institutions for the sake of personal aggrandizement. The Trumpian cause is held together by hatred of the Other. Because Trumpians live in a state of perpetual war, they need to continually invent existential foes—critical race theory, nongendered bathrooms, out-of-control immigration. They need to treat half the country, metropolitan America, as a moral cancer, and view the cultural and demographic changes of the past 50 years as an alien invasion. Yet pluralism is one of America’s oldest traditions; to conserve America, you have to love pluralism. As long as the warrior ethos dominates the GOP, brutality will be admired over benevolence, propaganda over discourse, confrontation over conservatism, dehumanization over dignity. A movement that has more affection for Viktor Orbán’s Hungary than for New York’s Central Park is neither conservative nor American. This is barren ground for anyone trying to plant Burkean seedlings.
I’m content, as my hero Isaiah Berlin put it, to plant myself instead on the rightward edge of the leftward tendency—in the more promising soil of the moderate wing of the Democratic Party. If its progressive wing sometimes seems to have learned nothing from the failures of government and to promote cultural stances that divide Americans, at least the party as a whole knows what year it is. In 1980, the core problem of the age was statism, in the form of communism abroad and sclerotic, dynamism-sapping bureaucracies at home. In 2021, the core threat is social decay. The danger we should be most concerned with lies in family and community breakdown, which leaves teenagers adrift and depressed, adults addicted and isolated. It lies in poisonous levels of social distrust, in deepening economic and persisting racial disparities that undermine the very goodness of America—in political tribalism that makes government impossible.
To reduce the economic chasm that separates class from class, to ease the financial anxiety that renders life unstable for many people, to support parenting so that children can grow up with more stability—these are the goals of a party committed to ameliorating, not exploiting, a growing sense of hopelessness and alienation, of vanishing opportunity. Daniel Patrick Moynihan’s brilliant dictum—which builds on a Burkean wisdom forged in a world of animosity and corrosive flux—has never been more worth heeding than it is now: The central conservative truth is that culture matters most; the central liberal truth is that politics can change culture.

Monday, December 20, 2021

The Point is to Stop - a farewell to self help coaching

I want to pass on some points, paraphrase, and central clips from what is essentially a swan song offered by Mark Manson in his latest newsletter - a newsletter whose contents I have mentioned in a number of previous MindBlog posts. This Manson essay hits me between the eyes, because I'm very aware that one of my main motivations for doing this MindBlog since Feb. 2006, with it's 5,220 posts (and counting) is that it has turned out to be valuable self therapy for Deric (with this abstracting of Manson's current article being one example). 

He begins by referencing an older article noting that 

...the best way to judge the usefulness of self-help advice is by now many people eventually leave it behind.
He notes that people who seek out self help..
...do so with two different mindsets... the "Doctor People" ...look to a book, website or seminar to cure their emotional ails... the "Coach People"...want a mentor or coach..They want strategies, roadmaps, to know the right moves...the problem is that Doctor People see personal growth as information that is to be learned rather than a skill that must be practiced...Self-awareness, managing emotions, empathy, vulnerability are skills ..it can take years to become somewhat good at them... Coach People are in it for the long haul.
But what the Coach People don't get is that the whole point is to eventually stop. It's to leave. Because unlike chess or basketball, there's no world championship for anger management. Nobody is going to give you a trophy for mindfulness...the skill curves are different...In basketball or chess, the better you get, the more effort is required to further improve...in personal growth, the better you get, the less effort is required to further improve...personal growth skills have positive feedback loops bakes into them.. like skiing downhill..it takes a lot of effort to get some speed going, but once you're on your way, the most effective thing you can do to gain speed is nothing.
...what the Coach People miss is that the whole point of this stuff, the way to 'win,' is to one day be free of consciously having to think about it...At some point, you just have to live your damn life...Coach People who identify as the "personal growth" not only get trapped by it, but are likely to bore you at dinner parties with their stories about their ayahuasca retreats.

And, at this point in the article, Mason declares that he is going to leave behind his career as a Coach Person, move on from the self help world he started writing a blog about in 2008, the blog being his own therapy as "I tried to sort through my own shit." 

And now,

I'm no longer the guy at the top of the ski hill struggling to get going. I feel like the guy flying down, full speed ahead..to continue writing about these topics feels like unnecessarily planting my poles into the snow...the standard roadmap for self-help authors when they produce a hit book is to spend the next 20-30 years regurgitating the same ideas over and over again in various formats, on various stages, cashing the checks as they go. To me that sounds about as interesting as sticking my dick in a light socket...I've spent a lot of the past few years anxious and insecure that I would "lose my audience," by stepping away from self-help content. It's taken me way too long to listen to my own advice and just not give a fuck.

Manson then describes how he plans to leave behind a repository (The Subtle Art School) of what he has worked so hard to learn the past ten years, and leave his blog as an archive for posterity. 


Thursday, December 16, 2021

The active grandparent hypothesis

Lieberman et al. suggest that selection in humans for lifelong physical activity, including during postreproductive years to provision offspring, promoted selection for energy allocation pathways which synergistically slow senescence and reduce vulnerability to many forms of chronic diseases. Here is their abstract (motivated readers can obtain a copy of the article from me):
The proximate mechanisms by which physical activity (PA) slows senescence and decreases morbidity and mortality have been extensively documented. However, we lack an ultimate, evolutionary explanation for why lifelong PA, particularly during middle and older age, promotes health. As the growing worldwide epidemic of physical inactivity accelerates the prevalence of noncommunicable diseases among aging populations, integrating evolutionary and biomedical perspectives can foster new insights into how and why lifelong PA helps preserve health and extend lifespans. Building on previous life-history research, we assess the evidence that humans were selected not just to live several decades after they cease reproducing but also to be moderately physically active during those postreproductive years. We next review the longstanding hypothesis that PA promotes health by allocating energy away from potentially harmful overinvestments in fat storage and reproductive tissues and propose the novel hypothesis that PA also stimulates energy allocation toward repair and maintenance processes. We hypothesize that selection in humans for lifelong PA, including during postreproductive years to provision offspring, promoted selection for both energy allocation pathways which synergistically slow senescence and reduce vulnerability to many forms of chronic diseases. As a result, extended human healthspans and lifespans are both a cause and an effect of habitual PA, helping explain why lack of lifelong PA in humans can increase disease risk and reduce longevity.

Tuesday, December 14, 2021

New articles on exercise and the brain

Gretchen Reynolds has done two recent brief reviews:

 The Quiet Brain of the Athlete describes work showing that the brains of fit, young athletes dial down extraneous noise and attend to important sounds better than those of other young people. 

And, 

 Staying physically active may protect the aging brain. Simple activities like walking boost immune cells in the brain that may help to keep memory sharp and even ward off Alzheimer’s disease.

Friday, December 10, 2021

Temporal Self-Compression

Brietzke and Meyer (open source) provide behavioral and neural evidence that our past and future selves are compressed as they move away from the present:  

Significance

For centuries, great thinkers have struggled to understand how people represent a personal identity that changes over time. Insight may come from a basic principle of perception: as objects become distant, they also become less discriminable or “compressed.” In Studies 1–3, we demonstrate that people’s ratings of their own personality become increasingly less differentiated as they consider more distant past and future selves. In Study 4, we found neural evidence that the brain compresses self-representations with time as well. When we peer out a window, objects close to us are in clear view, whereas distant objects are hard to tell apart. We provide evidence that self-perception may operate similarly, with the nuance of distant selves increasingly harder to perceive.
Abstract
A basic principle of perception is that as objects increase in distance from an observer, they also become logarithmically compressed in perception (i.e., not differentiated from one another), making them hard to distinguish. Could this basic principle apply to perhaps our most meaningful mental representation: our own sense of self? Here, we report four studies that suggest selves are increasingly non-discriminable with temporal distance from the present as well. In Studies 1 through 3, participants made trait ratings across various time points in the past and future. We found that participants compressed their past and future selves, relative to their present self. This effect was preferential to the self and could not be explained by the alternative possibility that individuals simply perceive arbitrary self-change with time irrespective of temporal distance. In Study 4, we tested for neural evidence of temporal self-compression by having participants complete trait ratings across time points while undergoing functional MRI. Representational similarity analysis was used to determine whether neural self-representations are compressed with temporal distance as well. We found evidence of temporal self-compression in areas of the default network, including medial prefrontal cortex and posterior cingulate cortex. Specifically, neural pattern similarity between self-representations was logarithmically compressed with temporal distance. Taken together, these findings reveal a “temporal self-compression” effect, with temporal selves becoming increasingly non-discriminable with distance from the present.

Wednesday, December 08, 2021

Severity and clinical course of depression correlates with altered connectivity in sensorimotor cortices.

Interesting work from Ray et al.,  

Significance

Research into neurobiology of depression primarily focuses on its complex psychological aspects. Here we propose an alternative approach and target sensorimotor alterations—a prominent but often neglected feature of depression. We demonstrated using resting-state functional MRI data and computational modeling that top-down and bottom-up information flow in sensory and motor cortices is altered with increasing depression severity in a way that is consistent with depression symptoms. Depression-associated changes were found to be consistent across sessions, amenable to treatment and of effect size sufficiently large to predict whether somebody has mild or severe depression. These results pave the way for an avenue of research into the neural underpinnings of mental health conditions.
Abstract
Functional neuroimaging research on depression has traditionally targeted neural networks associated with the psychological aspects of depression. In this study, instead, we focus on alterations of sensorimotor function in depression. We used resting-state functional MRI data and dynamic causal modeling (DCM) to assess the hypothesis that depression is associated with aberrant effective connectivity within and between key regions in the sensorimotor hierarchy. Using hierarchical modeling of between-subject effects in DCM with parametric empirical Bayes we first established the architecture of effective connectivity in sensorimotor cortices. We found that in (interoceptive and exteroceptive) sensory cortices across participants, the backward connections are predominantly inhibitory, whereas the forward connections are mainly excitatory in nature. In motor cortices these parities were reversed. With increasing depression severity, these patterns are depreciated in exteroceptive and motor cortices and augmented in the interoceptive cortex, an observation that speaks to depressive symptomatology. We established the robustness of these results in a leave-one-out cross-validation analysis and by reproducing the main results in a follow-up dataset. Interestingly, with (nonpharmacological) treatment, depression-associated changes in backward and forward effective connectivity partially reverted to group mean levels. Overall, altered effective connectivity in sensorimotor cortices emerges as a promising and quantifiable candidate marker of depression severity and treatment response.

Monday, December 06, 2021

The Science of Mind Reading

James Somers offers a fascinating article in the Nov. 29 issue of The New Yorker, which I recommend that you read. It describes the development of the technique of Latent Semantic Analysis (L.S.A) originating in the work of a psychologist named Charles Osgood nearly 70 years ago and now being applied to the analysis of fMRI recordings from people to infer what they are internally thinking or seeing.
In 2013, researchers at Google unleashed a descendant of it onto the text of the whole World Wide Web. Google’s algorithm turned each word into a “vector,” or point, in high-dimensional space. The vectors generated by the researchers’ program, word2vec, are eerily accurate: if you take the vector for “king” and subtract the vector for “man,” then add the vector for “woman,” the closest nearby vector is “queen.” Word vectors became the basis of a much improved Google Translate, and enabled the auto-completion of sentences in Gmail. Other companies, including Apple and Amazon, built similar systems. Eventually, researchers realized that the “vectorization” made popular by L.S.A. and word2vec could be used to map all sorts of things. Today’s facial-recognition systems have dimensions that represent the length of the nose and the curl of the lips, and faces are described using a string of coördinates in “face space.” Chess A.I.s use a similar trick to “vectorize” positions on the board. The technique has become so central to the field of artificial intelligence that, in 2017, a new, hundred-and-thirty-five-million-dollar A.I. research center in Toronto was named the Vector Institute. Matthew Botvinick, a professor at Princeton whose lab was across the hall from Norman’s, and who is now the head of neuroscience at DeepMind, Alphabet’s A.I. subsidiary, told me that distilling relevant similarities and differences into vectors was “the secret sauce underlying all of these A.I. advances.”

 


Subsequent sections of the article describe how machine learning has been brought to brain imaging with voxels of neural activity serving as dimensions in a kind of thought space.

...today’s thought-decoding researchers mostly look for specific thoughts that have been defined in advance. But a “general-purpose thought decoder,” Norman told me, is the next logical step for the research. Such a device could speak aloud a person’s thoughts, even if those thoughts have never been observed in an fMRI machine. In 2018, Botvinick, Norman’s hall mate, co-wrote a paper in the journal Nature Communications titled “Toward a Universal Decoder of Linguistic Meaning from Brain Activation.” Botvinick’s team had built a primitive form of what Norman described: a system that could decode novel sentences that subjects read silently to themselves. The system learned which brain patterns were evoked by certain words, and used that knowledge to guess which words were implied by the new patterns it encountered.

Friday, December 03, 2021

In praise of Sheeple - why we shouldn't always think for ourselves

A friend pointed out this interesting article by Ian Leslie, which I recommend that you read. I pass on a few clips at the end of his exposition:
...the human instinct to copy rather than think for ourselves is good for us, up to a point. Cultural anthropologists have done the most to establish that our instinct to copy parents and peers helps us to learn, to get along, to organise, to bond, and ultimately to build the shared behaviours that enable us to survive and progress. They’ve discovered that compared to other primates humans “over-imitate”: we copy even when there’s no reason to.
In a much-replicated experiment, a complicated-looking box is presented to chimps and the researchers demonstrate how to access a bit of food inside. They include some unnecessary steps: tapping the box three times, fiddling with a bolt, whatever. The chimps quickly work out all they need to do is pull a door and grab the food, and ignore the superfluous actions. Do this experiment with very small humans, however, and the kids copy all the actions. The chimps are more efficient and in a way more ‘rational’ but it’s the other primate which has built cities, ships and cathedrals.
Traditions we don’t understand ought not to be dismissed too quickly, since the collective intelligence of the past dwarves our own. In The Secret of Our Success, the anthropologist Joseph Henrich argues that individual humans are not nearly as smart as we think and that it is culture that makes us a successful species. The Naskapi, a foraging tribe from north-eastern Canada, hunt caribou. They have to decide where to hunt, which isn’t straightforward because if they visit one location too often the caribou know to stay away. The best hunting strategy therefore requires randomisation.
But individuals like to think they’re smart and left to their own devices, Naskapi hunters probably wouldn’t be satisfied with setting out in a random direction every day; they’d come up with brilliant plans which proved to be disastrous. Tradition saves them. To decide where to go, the hunters use a divination ritual which involves heating a caribou shoulder blade over hot coals until cracks and spots start to appear on it; the resulting pattern is then used as a map. In a sense it’s a mindless ritual, but it’s also a randomising device which helps the hunters overcome their decision-making biases.
Here’s what I like about the dupes. When everyone around them behaved in a certain way, their first thought wasn’t “I must be smarter than them”. It was, “They must know something I don’t”. There is an admirable humility to that, even if, in this case, it led them to say or do something absurd. The ability of individual humans to think for ourselves is crucial to progress; equally crucial is that we trust, sometimes unthinkingly, in judgements made by others, alive or dead. Societies where too few people are willing to question norms and traditions tend to stagnate and to perpetuate injustices. But there is a positive side to conformism, too. Just as in an imaginary nightclub on fire there’s a good chance that a passing group will lead you to an exit, there’s a good chance that whatever the people around you say is right, is right, even if you don’t fully understand why yet. Society functions best when we’re sheepish.

Thursday, December 02, 2021

What is a DAO? Who needs humans?

A DAO is a Decentralised Autonomous Organisation. My son pointed out this intriguing and also somewhat terrifying video to me. Like Mark Zuckerberg's corporate "Meta" fantasies another step towards tearing our evolved biolgical bodies and social brains away from the organic tactile contacts with each other for which they were designed.

 

Wednesday, December 01, 2021

The Science of Hugs?

Schultz describes an entertaining bit of work pursuing the obvious done by Düren et.al. Guys hugging each other use their arms differently than women do, more frequently doing a crisscross hug (on the left) than a neck-waist hug (on the right), most likely because the neck-waist hug feels a bit more intimate.

Without prompting the students on how to hug, the researchers found the crisscross style was more common, accounting for 66 out of 100 hugs. The preference for crisscross was especially prevalent in pairs of men, with 82% of 28 observed pairs opting for the style. Neither emotional closeness nor height had significant effects on the style of hugging; however, the researchers note that most participants were relatively close in height, and they guess that neck-waist might be more common when heights differ more drastically.

Tuesday, November 30, 2021

Cannabis use during pregnancy correlates with cortisol, anxiety, aggression, and hyperactivity in young children.

Sobering results from Rompala et al.

Significance

Cannabis use is becoming more prevalent, including during developmentally sensitive periods such as pregnancy. Here we find that maternal cannabis use is associated with increased cortisol, anxiety, aggression, and hyperactivity in young children. This corresponded with widespread reductions in immune-related gene expression in the placenta which correlated with anxiety and hyperactivity. Future studies are needed to examine the effects of cannabis on immune function during pregnancy as a potential regulatory mechanism shaping neurobehavioral development.
Abstract
While cannabis is among the most used recreational drugs during pregnancy, the impact of maternal cannabis use (mCB) on fetal and child development remains unclear. Here, we assessed the effects of mCB on psychosocial and physiological measures in young children along with the potential relevance of the in utero environment reflected in the placental transcriptome. Children (∼3 to 6 y) were assessed for hair hormone levels, neurobehavioral traits on the Behavioral Assessment System for Children (BASC-2) survey, and heart rate variability (HRV) at rest and during auditory startle. For a subset of children with behavioral assessments, placental specimens collected at birth were processed for RNA sequencing. Hair hormone analysis revealed increased cortisol levels in mCB children. In addition, mCB was associated with greater anxiety, aggression, and hyperactivity. Children with mCB also showed a reduction in the high-frequency component of HRV at baseline, reflecting reduced vagal tone. In the placenta, there was reduced expression of many genes involved in immune system function including type I interferon, neutrophil, and cytokine-signaling pathways. Finally, several of these mCB-linked immune genes organized into coexpression networks that correlated with child anxiety and hyperactivity. Overall, our findings reveal a relationship between mCB and immune response gene networks in the placenta as a potential mediator of risk for anxiety-related problems in early childhood.

Monday, November 29, 2021

An artificial neural network that responds to written words like our brain's word form area

Interesting work from Dehaene and collaborators:  

Significance

Learning to read results in the formation of a specialized region in the human ventral visual cortex. This region, the visual word form area (VWFA), responds selectively to written words more than to other visual stimuli. However, how neural circuits at this site implement an invariant recognition of written words remains unknown. Here, we show how an artificial neural network initially designed for object recognition can be retrained to recognize words. Once literate, the network develops a sparse neuronal representation of words that replicates several known aspects of the cognitive neuroscience of reading and leads to precise predictions concerning how a small set of neurons implement the orthographic stage of reading acquisition using a compositional neural code.
Abstract
The visual word form area (VWFA) is a region of human inferotemporal cortex that emerges at a fixed location in the occipitotemporal cortex during reading acquisition and systematically responds to written words in literate individuals. According to the neuronal recycling hypothesis, this region arises through the repurposing, for letter recognition, of a subpart of the ventral visual pathway initially involved in face and object recognition. Furthermore, according to the biased connectivity hypothesis, its reproducible localization is due to preexisting connections from this subregion to areas involved in spoken-language processing. Here, we evaluate those hypotheses in an explicit computational model. We trained a deep convolutional neural network of the ventral visual pathway, first to categorize pictures and then to recognize written words invariantly for case, font, and size. We show that the model can account for many properties of the VWFA, particularly when a subset of units possesses a biased connectivity to word output units. The network develops a sparse, invariant representation of written words, based on a restricted set of reading-selective units. Their activation mimics several properties of the VWFA, and their lesioning causes a reading-specific deficit. The model predicts that, in literate brains, written words are encoded by a compositional neural code with neurons tuned either to individual letters and their ordinal position relative to word start or word ending or to pairs of letters (bigrams).

Friday, November 26, 2021

Online spread of false information depends on cascade size

Juul and Ugander do an analysis of factors that influence the spread of false news, finding a central role for cascade size and suggesting that to limit the spread of false news, it may be enough to focus on reducing the mean “infectiousness” of the information.  

Significance

Do different types of information spread differently online? In recent years, studies have sought answers to such questions by comparing statistical properties of network paths taken by different kinds of content diffusing online. Here, we demonstrate the importance of controlling for correlations between properties being compared. In particular, we show that previously reported structural differences between diffusion paths of false and true news on Twitter disappear when comparing only cascades of the same size; differences between diffusion paths of images, videos, news, and petitions persist. Paired with a theoretical analysis of diffusion processes, our results suggest that, in order to limit the spread of false news, it may be enough to focus on reducing the mean “infectiousness” of the information.
Abstract
Do some types of information spread faster, broader, or further than others? To understand how information diffusions differ, scholars compare structural properties of the paths taken by content as it spreads through a network, studying so-called cascades. Commonly studied cascade properties include the reach, depth, breadth, and speed of propagation. Drawing conclusions from statistical differences in these properties can be challenging, as many properties are dependent. In this work, we demonstrate the essentiality of controlling for cascade sizes when studying structural differences between collections of cascades. We first revisit two datasets from notable recent studies of online diffusion that reported content-specific differences in cascade topology: an exhaustive corpus of Twitter cascades for verified true- or false-news content by Vosoughi et al. [S. Vosoughi, D. Roy, S. Aral. Science 359, 1146–1151 (2018)] and a comparison of Twitter cascades of videos, pictures, news, and petitions by Goel et al. [S. Goel, A. Anderson, J. Hofman, D. J. Watts. Manage. Sci. 62, 180–196 (2016)]. Using methods that control for joint cascade statistics, we find that for false- and true-news cascades, the reported structural differences can almost entirely be explained by false-news cascades being larger. For videos, images, news, and petitions, structural differences persist when controlling for size. Studying classical models of diffusion, we then give conditions under which differences in structural properties under different models do or do not reduce to differences in size. Our findings are consistent with the mechanisms underlying true- and false-news diffusion being quite similar, differing primarily in the basic infectiousness of their spreading process.

Thursday, November 25, 2021

Caution around the fountain of youth.

Lee et al. do a review "Antiaging diets: Separating fact from fiction" in Science Magazine. The link takes you to their summary, abstract, and a nice graphic. I pass on a Box 1 from the body of the article titled "reclaiming the term 'anti-aging'":
The phrase “antiaging” is greatly abused in popular culture, often for the purpose of marketing cosmetic procedures or unproven nutritional supplements purported to slow or reverse aging. This has the unfortunate consequence of creating confusion among the general public and diminishing the impact of legitimate scientific discovery. Here, we define “antiaging” as delaying or reversing biological aging by targeting the established molecular mechanisms of aging, which have been formalized as “hallmarks” or “pillars” of aging (93, 94). Effective antiaging interventions in laboratory animals increase both median and maximum population life span and broadly delay the onset and progression of many age-related functional declines and diseases. The latter effect is often referred to as “extending health span,” which is a qualitative term referring to the period of life free from chronic disease and disability (95). Recent studies show that at least some antiaging interventions, such as the drug rapamycin, can reverse functional declines across multiple tissues in aged animals (96). On the basis of this definition, there are as yet no clinically validated antiaging interventions in humans. However, there is some evidence consistent with antiaging effects for CR and related diets in humans as well as a small number of putative geroprotective compounds, including metformin and rapamycin (97).
93. C. López-Otín, M. A. Blasco, L. Partridge, M. Serrano, G. Kroemer, The hallmarks of aging. Cell 153, 1194–1217 (2013).
94. B. K. Kennedy, S. L. Berger, A. Brunet, J. Campisi, A. M. Cuervo, E. S. Epel, C. Franceschi, G. J. Lithgow, R. I. Morimoto, J. E. Pessin, T. A. Rando, A. Richardson, E. E. Schadt, T. Wyss-Coray, F. Sierra, Geroscience: Linking aging to chronic disease. Cell 159, 709–713 (2014).
95 M. Kaeberlein, How healthy is the healthspan concept? Geroscience 40, 361–364 (2018).
96 R. Selvarani, S. Mohammed, A. Richardson, Effect of rapamycin on aging and age-related diseases-past and future. Geroscience 43, 1135–1158 (2021).
97 M. B. Lee, M. Kaeberlein, Translational Geroscience: From invertebrate models to companion animal and human interventions. Transl. Med. Aging 2, 15–29 (2018).

Wednesday, November 24, 2021

Volatile hexadecanal emitted by babies could make men more docile and women more aggressive

Interesting observations from Mishor et al.:
In terrestrial mammals, body volatiles can effectively trigger or block conspecific aggression. Here, we tested whether hexadecanal (HEX), a human body volatile implicated as a mammalian-wide social chemosignal, affects human aggression. 

Using validated behavioral paradigms, we observed a marked dissociation: Sniffing HEX blocked aggression in men but triggered aggression in women. Next, using functional brain imaging, we uncovered a pattern of brain activity mirroring behavior: In both men and women, HEX increased activity in the left angular gyrus, an area implicated in perception of social cues. HEX then modulated functional connectivity between the angular gyrus and a brain network implicated in social appraisal (temporal pole) and aggressive execution (amygdala and orbitofrontal cortex) in a sex-dependent manner consistent with behavior: increasing connectivity in men but decreasing connectivity in women. These findings implicate sex-specific social chemosignaling at the mechanistic heart of human aggressive behavior.
From the author's discussion:
....what behavioral setting could underlie selection for a body volatile that increases aggression in women but decreases it in men? Or in other words, what could be the ecological relevance of these results? In this respect, we call attention to the setting of infant rearing. Parents across cultures are encouraged to sniff their babies, an action that activates brain reward circuits in women. Our results imply that sniffing babies may increase aggression in mothers but decrease aggression in fathers. Whereas maternal aggression has a direct positive impact on offspring survival in the animal world, paternal aggression has a negative impact on offspring survival. This is because maternal aggression (also termed maternal defense behavior) is typically directed at intruders, yet paternal aggression, and more so nonpaternal male aggression, is often directed at the offspring themselves. If babies had a mechanism at their disposal that increased aggression in women but decreased it in men, this would likely increase their survival. With the hypothesis in mind that HEX provides babies with exactly such a mechanism, we first note that infant rearing is the one social setting where humans have extensive exposure to conspecific feces, a rich source of HEX. We also turned to a recently published analysis of baby-head volatiles, yet in contrast to our hypothesis, this report did not mention HEX. We turned to the authors of that report, who explained that the published analysis was not tuned to the near semivolatile range of HEX. With our question in mind, they (now coauthors T.U. and M.O.) sampled an additional 19 babies, using gas chromatography (GC) × GC–mass spectrometry, and observed that HEX is one of the most abundant baby-head volatiles...

Tuesday, November 23, 2021

Socrates, Diderot, and Wolpert on Writing and Printing

I have to pass on these quotes sent by one my Chaos and Complexity Seminar colleagues at the University of Wisconsin:
Socrates on writing, from Phaedrus, 275a-b
"For this invention will produce forgetfulness in the minds of those who learn to use it, because they will not practice their memory. Their trust in writing, produced by external characters which are no part of themselves, will discourage the use of their own memory within them. You have invented an elixir not of memory, but of reminding; and you offer your pupils the appearance of wisdom, not true wisdom, for they will read many things without instruction and will therefore seem to know many things, when they are for the most part ignorant and hard to get along with, since they are not wise, but only appear wise."
Denis Diderot, Encyclopédie, 1755
"As long as the centuries continue to unfold, the number of books will grow continually, and one can predict that a time will come when it will be almost as difficult to learn anything from books as from the direct study of the whole universe. It will be almost as convenient to search for some bit of truth concealed in nature as it will be to find it hidden away in an immense multitude of bound volumes."
Lewis Wolpert (1929--2021) Lewis Wolpert - Scientist - Web of Stories
"Reading rots the mind."

Monday, November 22, 2021

Fluid intelligence and the locus coeruleus-norepinephrine system

Tsukahara and Engle suggest that the cognitive mechanisms of fluid intelligence map onto the locus coeruleus–norepinephrine system. I pass on their introductory paragraph (the link takes you to their abstract, which I think is less informative):
In this article, we outline what we see as a potentially important relationship for understanding the biological basis of intelligence: that is, the relationship between fluid intelligence and the locus coeruleus–norepinephrine system. This is largely motivated by our findings that baseline pupil size is related to fluid intelligence; the larger the pupils, the higher the fluid intelligence. The connection to the locus coeruleus is based on research showing that the size of the pupil can be used as an indicator of locus coeruleus activity. A large body of research on the locus coeruleus–norepinephrine system in animal and human studies has shown how this system is critical for an impressively wide range of behaviors and cognitive processes, from regulating sleep/wake cycles, to sensation and perception, attention, learning and memory, decision making, and more. The locus coeruleus–norepinephrine system achieves this primarily through its widespread projection system throughout the cortex, strong connections with the prefrontal cortex, and the effect of norepinephrine at many levels of brain function. Given the broad role of this system in behavior, cognition, and brain function, we propose that the locus coeruleus–norepinephrine system is essential for understanding the biological basis of intelligence.

Friday, November 19, 2021

Drifting nerve assemblies can maintain persistent memories

A prevailing model has been that a memory in our brains is stored in a specific set of nerve connections, that, like a book in a library, stays where it belongs. Over the past few years, however, it has become more and more clear that 'representational plasticity' may be the norm. A recent article by Kossio et al. proposes a contrasting memory model (motivated readers can obtain the whole article from me):
Change is ubiquitous in living beings. In particular, the connectome and neural representations can change. Nevertheless, behaviors and memories often persist over long times. In a standard model, associative memories are represented by assemblies of strongly interconnected neurons. For faithful storage these assemblies are assumed to consist of the same neurons over time. Here we propose a contrasting memory model with complete temporal remodeling of assemblies, based on experimentally observed changes of synapses and neural representations. The assemblies drift freely as noisy autonomous network activity and spontaneous synaptic turnover induce neuron exchange. The gradual exchange allows activity-dependent and homeostatic plasticity to conserve the representational structure and keep inputs, outputs, and assemblies consistent. This leads to persistent memory. Our findings explain recent experimental results on temporal evolution of fear memory representations and suggest that memory systems need to be understood in their completeness as individual parts may constantly change.
Here is an explanatory graphic from the article:
Assembly drift and persistent memory. (A) At two nearby times a similar ensemble of neurons forms the neural representation of, for example, “apple” (compare the blue-colored assembly neurons at the first and the second time point). At distant times the representation consists of completely different ensembles (blue-colored assembly neurons at the first and the third time point). Due to their gradual change, temporally distant representations are indirectly related via ensembles in the time period between them. (B) Parts of a thread possess the same form of indirect relation: Nearby parts are composed of similar ensembles of fibers, while distant ones consist of different ensembles, which are connected by those in between. (C) The complete change of memory representations still allows for stable behavior. In the schematic, a tasty apple is perceived. At different times, this triggers different ensembles that presently form the representation of “apple”; see A. Assembly activation initiates a reaching movement toward the apple, despite the dissimilarity of the activated neuron ensembles. Memory and behavior are conserved because the gradual change of assembly neurons enables the inputs (green) and outputs (orange) to track the neural representation.

Wednesday, November 17, 2021

Our brainstems respond to fake therapies and fake side effects.

Here is the abstract from a Journal of Neuroscience paper by Crawford et al. titled "Brainstem mechanisms of pain modulation: a within-subjects 7T fMRI study of Placebo Analgesic and Nocebo Hyperalgesic Responses":
Pain perception can be powerfully influenced by an individual’s expectations and beliefs. Whilst the cortical circuitry responsible for pain modulation has been thoroughly investigated, the brainstem pathways involved in the modulatory phenomena of placebo analgesia and nocebo hyperalgesia remain to be directly addressed. This study employed ultra-high field 7 Tesla functional MRI (fMRI) to accurately resolve differences in brainstem circuitry present during the generation of placebo analgesia and nocebo hyperalgesia in healthy human participants (N = 25; 12 Male). Over two successive days, through blinded application of altered thermal stimuli, participants were deceptively conditioned to believe that two inert creams labelled ‘lidocaine’ (placebo) and ‘capsaicin’ (nocebo) were acting to modulate their pain relative to a third ‘Vaseline’ (control) cream. In a subsequent test phase, fMRI image sets were collected whilst participants were given identical noxious stimuli to all three cream sites. Pain intensity ratings were collected and placebo and nocebo responses determined. Brainstem-specific fMRI analysis revealed altered activity in key pain-modulatory nuclei, including a disparate recruitment of the periaqueductal gray (PAG) – rostral ventromedial medulla (RVM) pathway when both greater placebo and nocebo effects were observed. Additionally, we found that placebo and nocebo responses differentially activated the parabrachial nucleus but overlapped in their engagement of the substantia nigra and locus coeruleus. These data reveal that placebo and nocebo effects are generated through differential engagement of the PAG-RVM pathway, which in concert with other brainstem sites likely influence the experience of pain by modulating activity at the level of the dorsal horn.

Snippets of Bach

To give MindBlog readers a bit of a break from brain and mind posts, I want to point out that the New York Times has a great series of articles that present roughly five minutes of music chosen by artists and composers to make you fall in love with different genres of classical music: piano, opera, cello, Mozart, 21st-century composers, violin, Baroque music, sopranos, Beethoven, flute, string quartets, tenors, Brahms, choral music, percussion, symphonies, Stravinsky, trumpet and Maria Callas. 

 

The most recent installment presents the stirring, consoling music of Johann Sebastian Bach, the grand master of the Western classical tradition.

Monday, November 15, 2021

Coevolution of tool use and language - shared syntactic processes and basal ganglia substrates

Thibault et al. show that tool use and language share syntactic processes. Functional magnetic resonance imaging reveals that tool use and syntax in language elicit similar patterns of brain activation within the basal ganglia. This indicates common neural resources for the two abilities. Indeed, learning transfer occurs across the two domains: Tool-use motor training improves syntactic processing in language and, reciprocally, linguistic training with syntactic structures improves tool use. Here is their entire structured abstract:   

INTRODUCTION

Tool use is a hallmark of human evolution. Beyond its sensorimotor components, the complexity of which has been extensively investigated, tool use affects cognition from a different perspective. Indeed, tool use requires integrating an external object as a body part and embedding its functional structure in the motor program. This adds a hierarchical level into the motor plan of manual actions, subtly modifying the relationship between interdependent subcomponents. Embedded structures also exist in language, and syntax is the cognitive function handling these linguistic hierarchies. One example is center-embedded object-relative clauses: “The poet [that the scientist admires] reads the paper.” Accordingly, researchers have advanced a role for syntax in action and the existence of similarities between the processes underlying tool use and language, so that shared neural resources for a common cognitive function could be at stake.
RATIONALE
We first tested the existence of shared neural substrates for tool use and syntax in language. Second, we tested the prediction that training one ability should affect performance in the other. In a first experiment, we measured participants’ brain activity with functional magnetic resonance imaging during tool use or, as a control, manual actions. In separate runs, the same participants performed a linguistic task on complex syntactic structures. We looked for common activations between tool use and the linguistic task, predicting similar patterns of activity if they rely on common neural resources. In further behavioral experiments, we tested whether motor training with the tool selectively improves syntactic performance in language and if syntactic training in language, in turn, selectively improves motor performance with the tool.
RESULTS
Tool-use planning and complex syntax processing (i.e., object relatives) elicited neural activity anatomically colocalized within the basal ganglia. A control experiment ruled out verbal working memory and manual (i.e., without a tool) control processes as an underlying component of this overlap. Multivariate analyses revealed similar spatial distributions of neural patterns prompted by tool-use planning and object-relative processing. This agrees with the recruitment of the same neural resources by both abilities and with the existence of a supramodal syntactic function. The shared neurofunctional resources were moreover reflected behaviorally by cross-domain learning transfer. Indeed, tool-use training significantly improved linguistic performance with complex syntactic structures. No learning transfer was observed on language syntactic abilities if participants trained without the tool. The reverse was also true: Syntactic training with complex sentences improved motor performance with the tool more than motor performance in a task without the tool and matched for sensorimotor difficulty. No learning transfer was observed on tool use if participants trained with simpler syntactic structures in language.
CONCLUSION
These findings reveal the existence of a supramodal syntactic function that is shared between language and motor processes. As a consequence, training tool-use abilities improves linguistic syntax and, reciprocally, training linguistic syntax abilities improves tool use. The neural mechanisms allowing for boosting performance in one domain by training syntax in the other may involve priming processes through preactivation of common neural resources, as well as short-term plasticity within the shared network. Our findings point to the basal ganglia as the neural site of supramodal syntax that handles embedded structures in either domain and also support longstanding theories of the coevolution of tool use and language in humans.

Friday, November 12, 2021

Freedom From Illusion

A friend who attended the lecture I gave last Sunday (A New Vision of how our Minds Work), and mentioned in a Monday post, sent me an article from The Buddhist Review "TRICYCLE" by Pema Düddul titled "Freedom From Illusion". If you scan both texts, I suspect you will find, as I do, a striking consonance between the neuroscientific and Buddhist perspectives on "Illusion." 

From the beginning of the Düddul article:

A shooting star, a clouding of the sight, 
a lamp, an illusion, a drop of dew, a bubble, 
a dream, a lightning’s flash, a thunder cloud: 
this is the way one should see the conditioned.
This revered verse from the Diamond Sutra points to one of Buddhism’s most profound yet confounding truths—the illusory nature of all things. The verse is designed to awaken us to ultimate reality, specifically to the fact that all things, especially thoughts and feelings, are the rainbow-like display of the mind. One of the Tibetan words for the dualistic mind means something like “a magician creating illusions.” As my teacher Ngakpa Karma Lhundup Rinpoche explained: “All of our thoughts are magical illusions created by our mind. We get trapped, carried away by our own illusions. We forget that we are the magician in the first place!”
Compare this with my talk's description of predictive processing, and how what we see, hear, touch, taste, and smell are largely simulations or illusions about the world. Here is a summary sentence in one of my slides, taken from a lecture by Ruben Laukkonen, in which I replace his last word, 'fantasies,' with the word 'illusions.'
Everything we do and experience is in service of reducing surprises by fulfilling illusions.

Wednesday, November 10, 2021

Computational evidence that predictive processing shapes language comprehension mechanisms in the brain.

Having just posted a lecture on predictive processing that I gave two days ago, I come across this fascinating work from Schrimpf et al.:  

Significance

Language is a quintessentially human ability. Research has long probed the functional architecture of language in the mind and brain using diverse neuroimaging, behavioral, and computational modeling approaches. However, adequate neurally-mechanistic accounts of how meaning might be extracted from language are sorely lacking. Here, we report a first step toward addressing this gap by connecting recent artificial neural networks from machine learning to human recordings during language processing. We find that the most powerful models predict neural and behavioral responses across different datasets up to noise levels. Models that perform better at predicting the next word in a sequence also better predict brain measurements—providing computationally explicit evidence that predictive processing fundamentally shapes the language comprehension mechanisms in the brain.
Abstract
The neuroscience of perception has recently been revolutionized with an integrative modeling approach in which computation, brain function, and behavior are linked across many datasets and many computational models. By revealing trends across models, this approach yields novel insights into cognitive and neural mechanisms in the target domain. We here present a systematic study taking this approach to higher-level cognition: human language processing, our species’ signature cognitive skill. We find that the most powerful “transformer” models predict nearly 100% of explainable variance in neural responses to sentences and generalize across different datasets and imaging modalities (functional MRI and electrocorticography). Models’ neural fits (“brain score”) and fits to behavioral responses are both strongly correlated with model accuracy on the next-word prediction task (but not other language tasks). Model architecture appears to substantially contribute to neural fit. These results provide computationally explicit evidence that predictive processing fundamentally shapes the language comprehension mechanisms in the human brain.

Monday, November 08, 2021

A MindBlog lecture - A New Vision of how our Minds Work

Yesterday I gave a short talk to the Austin Rainbow Forum discussion group that I started up with several other members of the Austin Prime Timers in January 2018. As I promised at the outset of the talk, which was fairly intense, I am now putting a PDF of the lecture text and slides on my website, and here am passing it on to MindBlog readers who might be interested in having a look. Here is the second slide of the talk, listing its topics:

 


It’s Quitting Season

I want to pass on two articles with the similar themes of people taking stock of their lives and deciding to stop making themselves unhappy. The piece by Crouse and Ferguson is a video, by and directed towards, Millenials, with the following introductory text:
It’s been a brutal few years. But we’ve gritted through. We’ve spent time languishing. We’ve had one giant national burnout. And now, finally, we’re quitting...We are quitting our jobs. Our cities. Our marriages. Even our Twitter feeds...And as we argue in the video, we’re not quitting because we’re weak. We’re quitting because we’re smart...younger Americans like 18-year-old singer Olivia Rodrigo and the extraordinary Simone Biles are barely old enough to rent a car but they are already teaching us about boundaries. They’ve seen enough hollowed-out millennials to know what the rest of us are learning: Don’t be a martyr to grit.
I feel some personal resonance with points made about a whole career path in the piece by Arthur Brooks, To Be Happy, Hide From the Spotlight, because this clip nails a part of the reason I keep driving myself to performances (writing, lecturing, music) by rote habit:
Assuming that you aren’t a pop star or the president, fame might seem like an abstract problem. The thing is, fame is relative, and its cousin, prestige — fame among a particular group of people — is just as fervently chased in smaller communities and fields of expertise. In my own community of academia, honors and prestige can be highly esoteric but deeply desired.
I suggest you read the whole article, but here are a few further clips:
Even if a person’s motive for fame is to set a positive example, it mirrors the other, less flattering motives insofar as it depends on other people’s opinions. And therein lies the happiness problem. Thomas Aquinas wrote in the 13th century, “Happiness is in the happy. But honor is not in the honored.” ...research shows that fame ...based on what scholars call extrinsic rewards... brings less happiness than intrinsic rewards...fame has become a form of addiction. This is especially true in the era of social media, which allows almost anyone with enough motivation to achieve recognition by some number of strangers...this is not a new phenomenon. The 19th-century philosopher Arthur Schopenhauer said fame is like seawater: “The more we have, the thirstier we become.”
No social scientists I am aware of have created a quantitative misery index of fame. But the weight of the indirect evidence above, along with the testimonies of those who have tasted true fame in their time, should be enough to show us that it is poisonous. It is “like a river, that beareth up things light and swollen,” said Francis Bacon, “and drowns things weighty and solid.” Or take it from Lady Gaga: “Fame is prison.”
...Pay attention to when you are seeking fame, prestige, envy, or admiration—especially from strangers. Before you post on social media, for example, ask yourself what you hope to achieve with it...Say you want to share a bit of professional puffery or photos of your excellent beach body. The benefit you experience is probably the little hit of dopamine you will get as you fire it off while imagining the admiration or envy others experience as they see it. The cost is in the reality of how people will actually see your post (and you): Research shows that people will largely find your boasting to be annoying—even if you disguise it with a humblebrag—and thus admire you less, not more. As Shakespeare helpfully put it, “Who knows himself a braggart, / Let him fear this, for it will come to pass / that every braggart shall be found an ass.”
The poet Emily Dickinson called fame a “fickle food / Upon a shifting plate.” But far from a harmless meal, “Men eat of it and die.” It’s a good metaphor, because we have the urge to consume all kinds of things that appeal to some anachronistic neurochemical impulse but that nevertheless will harm us. In many cases—tobacco, drugs of abuse, and, to some extent, unhealthy foods—we as a society have recognized these tendencies and taken steps to combat them by educating others about their ill effects.
Why have we failed to do so with fame? None of us, nor our children, will ever find fulfillment through the judgment of strangers. The right rule of thumb is to treat fame like a dangerous drug: Never seek it for its own sake, teach your kids to avoid it, and shun those who offer it.

Friday, November 05, 2021

Variability, not stereotypical expressions, in facial portraying of emotional states.

Barrett and collaborators use a novel method to offer more evidence against reliable mapping between certain emotional states and facial muscle movements:
It is long hypothesized that there is a reliable, specific mapping between certain emotional states and the facial movements that express those states. This hypothesis is often tested by asking untrained participants to pose the facial movements they believe they use to express emotions during generic scenarios. Here, we test this hypothesis using, as stimuli, photographs of facial configurations posed by professional actors in response to contextually-rich scenarios. The scenarios portrayed in the photographs were rated by a convenience sample of participants for the extent to which they evoked an instance of 13 emotion categories, and actors’ facial poses were coded for their specific movements. Both unsupervised and supervised machine learning find that in these photographs, the actors portrayed emotional states with variable facial configurations; instances of only three emotion categories (fear, happiness, and surprise) were portrayed with moderate reliability and specificity. The photographs were separately rated by another sample of participants for the extent to which they portrayed an instance of the 13 emotion categories; they were rated when presented alone and when presented with their associated scenarios, revealing that emotion inferences by participants also vary in a context-sensitive manner. Together, these findings suggest that facial movements and perceptions of emotion vary by situation and transcend stereotypes of emotional expressions. Future research may build on these findings by incorporating dynamic stimuli rather than photographs and studying a broader range of cultural contexts.
This perspective is opposite to that expressed by Cowen, Keltner et al. who use another novel method to reach opposite conclusions, in work that was noted in MindBlog's 12/29/20 post, along with some reservations about their conclusions.

Wednesday, November 03, 2021

People mistake the internet’s knowledge for their own

Fascinating experiments from Adrian Ward:   

Significance

In the current digital age, people are constantly connected to online information. The present research provides evidence that on-demand access to external information, enabled by the internet and search engines like Google, blurs the boundaries between internal and external knowledge, causing people to believe they could—or did—remember what they actually just found. Using Google to answer general knowledge questions artificially inflates peoples’ confidence in their own ability to remember and process information and leads to erroneously optimistic predictions regarding how much they will know without the internet. When information is at our fingertips, we may mistakenly believe that it originated from inside our heads.
Abstract
People frequently search the internet for information. Eight experiments (n = 1,917) provide evidence that when people “Google” for online information, they fail to accurately distinguish between knowledge stored internally—in their own memories—and knowledge stored externally—on the internet. Relative to those using only their own knowledge, people who use Google to answer general knowledge questions are not only more confident in their ability to access external information; they are also more confident in their own ability to think and remember. Moreover, those who use Google predict that they will know more in the future without the help of the internet, an erroneous belief that both indicates misattribution of prior knowledge and highlights a practically important consequence of this misattribution: overconfidence when the internet is no longer available. Although humans have long relied on external knowledge, the misattribution of online knowledge to the self may be facilitated by the swift and seamless interface between internal thought and external information that characterizes online search. Online search is often faster than internal memory search, preventing people from fully recognizing the limitations of their own knowledge. The internet delivers information seamlessly, dovetailing with internal cognitive processes and offering minimal physical cues that might draw attention to its contributions. As a result, people may lose sight of where their own knowledge ends and where the internet’s knowledge begins. Thinking with Google may cause people to mistake the internet’s knowledge for their own.

Monday, November 01, 2021

What the mind is - similarities and differences in concepts of mental life in five cultures

From Weisman et al., who do a fascinating study of cognitive structures 'from the bottom up', allowing data to give rise to ontological structures, rather than working 'from the top down' by using a theory to guide hypothesis-driven data collection. :
How do concepts of mental life vary across cultures? By asking simple questions about humans, animals and other entities – for example, ‘Do beetles get hungry? Remember things? Feel love?’ – we reconstructed concepts of mental life from the bottom up among adults (N = 711) and children (ages 6–12 years, N = 693) in the USA, Ghana, Thailand, China and Vanuatu. This revealed a cross-cultural and developmental continuity: in all sites, among both adults and children, cognitive abilities travelled separately from bodily sensations, suggesting that a mind–body distinction is common across diverse cultures and present by middle childhood. Yet there were substantial cultural and developmental differences in the status of social–emotional abilities – as part of the body, part of the mind or a third category unto themselves. Such differences may have far-reaching social consequences, whereas the similarities identify aspects of human understanding that may be universal.

Friday, October 29, 2021

People listening to the same story synchronize their heart rates.

Several studies have shown that people paying attention to the same videos or listening to the same stories show similar brain activity, as measured by electroencephalogram (EEG). Electrocardiogram (EKG) measurements are experimentally much easier to perform. Pérez et al. now show that heart rates of participants of their study measured by EKG tended to speed up or slow down at the same points in the story, demonstrating that conscious processing of narrative stimuli synchronizes heart rate between individuals. Here is their abstract:  

Highlights

• Narrative stimuli can synchronize fluctuations of heart rate between individuals 
• This interpersonal synchronization is modulated by attention and predicts memory 
• These effects on heart rate cannot be explained by modulation of respiratory patterns 
• Synchrony is lower in patients with disorders of consciousness
Summary
Heart rate has natural fluctuations that are typically ascribed to autonomic function. Recent evidence suggests that conscious processing can affect the timing of the heartbeat. We hypothesized that heart rate is modulated by conscious processing and therefore dependent on attentional focus. To test this, we leverage the observation that neural processes synchronize between subjects by presenting an identical narrative stimulus. As predicted, we find significant inter-subject correlation of heart rate (ISC-HR) when subjects are presented with an auditory or audiovisual narrative. Consistent with our hypothesis, we find that ISC-HR is reduced when subjects are distracted from the narrative, and higher ISC-HR predicts better recall of the narrative. Finally, patients with disorders of consciousness have lower ISC-HR, as compared to healthy individuals. We conclude that heart rate fluctuations are partially driven by conscious processing, depend on attentional state, and may represent a simple metric to assess conscious state in unresponsive patients.

Wednesday, October 27, 2021

What are our brains doing when they are (supposedly) doing nothing?

Pezullo et al. address the question of this post's title in an article in Trends in Cognitive Sciences: "The secret life of predictive brains: what's spontaneous activity for?" (motivated readers can obtain a PDF of the article by emailing me). They suggest an explanation for why brains are constantly active, displaying sophisticated dynamical patterns of spontaneous activity, even when not engaging in tasks or receiving external sensory stimuli. I pass on the article highlights and summary: 
Spontaneous brain dynamics are manifestations of top-down dynamics of generative models detached from action–perception cycles. 
Generative models constantly produce top-down dynamics, but we call them expectations and attention during task engagement and spontaneous activity at rest. 
Spontaneous brain dynamics during resting periods optimize generative models for future interactions by maximizing the entropy of explanations in the absence of specific data and reducing model complexity. 
Low-frequency brain fluctuations during spontaneous activity reflect transitions between generic priors consisting of low-dimensional representations and connectivity patterns of the most frequent behavioral states. 
High-frequency fluctuations during spontaneous activity in the hippocampus and other regions may support generative replay and model learning.
Brains at rest generate dynamical activity that is highly structured in space and time. We suggest that spontaneous activity, as in rest or dreaming, underlies top-down dynamics of generative models. During active tasks, generative models provide top-down predictive signals for perception, cognition, and action. When the brain is at rest and stimuli are weak or absent, top-down dynamics optimize the generative models for future interactions by maximizing the entropy of explanations and minimizing model complexity. Spontaneous fluctuations of correlated activity within and across brain regions may reflect transitions between ‘generic priors’ of the generative model: low dimensional latent variables and connectivity patterns of the most common perceptual, motor, cognitive, and interoceptive states. Even at rest, brains are proactive and predictive.

Monday, October 25, 2021

Scientific fields don't advance if too many papers are published.

Fascinating work from Chu and Evans

Significance

The size of scientific fields may impede the rise of new ideas. Examining 1.8 billion citations among 90 million papers across 241 subjects, we find a deluge of papers does not lead to turnover of central ideas in a field, but rather to ossification of canon. Scholars in fields where many papers are published annually face difficulty getting published, read, and cited unless their work references already widely cited articles. New papers containing potentially important contributions cannot garner field-wide attention through gradual processes of diffusion. These findings suggest fundamental progress may be stymied if quantitative growth of scientific endeavors—in number of scientists, institutes, and papers—is not balanced by structures fostering disruptive scholarship and focusing attention on novel ideas.
Abstract
In many academic fields, the number of papers published each year has increased significantly over time. Policy measures aim to increase the quantity of scientists, research funding, and scientific output, which is measured by the number of papers produced. These quantitative metrics determine the career trajectories of scholars and evaluations of academic departments, institutions, and nations. Whether and how these increases in the numbers of scientists and papers translate into advances in knowledge is unclear, however. Here, we first lay out a theoretical argument for why too many papers published each year in a field can lead to stagnation rather than advance. The deluge of new papers may deprive reviewers and readers the cognitive slack required to fully recognize and understand novel ideas. Competition among many new ideas may prevent the gradual accumulation of focused attention on a promising new idea. Then, we show data supporting the predictions of this theory. When the number of papers published per year in a scientific field grows large, citations flow disproportionately to already well-cited papers; the list of most-cited papers ossifies; new papers are unlikely to ever become highly cited, and when they do, it is not through a gradual, cumulative process of attention gathering; and newly published papers become unlikely to disrupt existing work. These findings suggest that the progress of large scientific fields may be slowed, trapped in existing canon. Policy measures shifting how scientific work is produced, disseminated, consumed, and rewarded may be called for to push fields into new, more fertile areas of study.

Friday, October 22, 2021

Metabolism modulates network synchrony in the aging brain

Wow, this work from Weistuch et al. temps me to reconsider my decision to stay away from the various mitochondrial metabolism stimulating supplements I have experimented with over the past 10-15 years (they made me a bit hyper). It has been hypothesized that declining glucose metabolism in older brains drives the loss of high-cost (integrated) functional activities (activities of the sort I'm trying to carry out at the moment in cobbling together a coherent lecture from diverse sources). From the paper's introduction:
We draw on two types of experimental evidence. First, as established using positron emission tomography, older brains show reduced glucose metabolism. Second, as established by functional MRI (fMRI), aging is associated with weakened functional connectivity (FC; i.e., reduced communication [on average] between brain regions). Combining both observations suggests that impaired glucose metabolism may underlie changes in FC. Supporting this link are studies showing disruptions similar to those seen with aging in type 2 diabetic subjects.

The Significance Statement and Abstract:  

Significance

How do brains adapt to changing resource constraints? This is particularly relevant in the aging brain, for which the ability of neurons to utilize their primary energy source, glucose, is diminished. Through experiments and modeling, we find that changes to brain activity patterns with age can be understood in terms of decreasing metabolic activity. Specifically, we find that older brains approach a critical point in our model, enabling small changes in metabolic activity to give rise to an abrupt reconfiguration of functional brain networks.
Abstract
Brain aging is associated with hypometabolism and global changes in functional connectivity. Using functional MRI (fMRI), we show that network synchrony, a collective property of brain activity, decreases with age. Applying quantitative methods from statistical physics, we provide a generative (Ising) model for these changes as a function of the average communication strength between brain regions. We find that older brains are closer to a critical point of this communication strength, in which even small changes in metabolism lead to abrupt changes in network synchrony. Finally, by experimentally modulating metabolic activity in younger adults, we show how metabolism alone—independent of other changes associated with aging—can provide a plausible candidate mechanism for marked reorganization of brain network topology.

Wednesday, October 20, 2021

A debate over stewardship of global collective behavior

In this post I'm going to pass on the abstract of a PNAS perspective piece by Bak-Coleman et al., a critique by Cheong and Jones and a reply to the critique by Bak-Coleman and Bergstrom. First the Bak-Coleman et al. abstract:
Collective behavior provides a framework for understanding how the actions and properties of groups emerge from the way individuals generate and share information. In humans, information flows were initially shaped by natural selection yet are increasingly structured by emerging communication technologies. Our larger, more complex social networks now transfer high-fidelity information over vast distances at low cost. The digital age and the rise of social media have accelerated changes to our social systems, with poorly understood functional consequences. This gap in our knowledge represents a principal challenge to scientific progress, democracy, and actions to address global crises. We argue that the study of collective behavior must rise to a “crisis discipline” just as medicine, conservation, and climate science have, with a focus on providing actionable insight to policymakers and regulators for the stewardship of social systems.
The critique by Cheong and Jones:
In vivid detail, Bak-Coleman et al. describe explosively multiplicative global pathologies of scale posing existential risk to humanity. They argue that the study of collective behavior in the age of digital social media must rise to a “crisis discipline” dedicated to averting global ruin through the adaptive manipulation of social dynamics and the emergent phenomenon of collective behavior. Their proposed remedy is a massive global, multidisciplinary coalition of scientific experts to discover how the “dispersed networks” of digital media can be expertly manipulated through “urgent, evidence-based research” to “steward” social dynamics into “rapid and effective collective behavioral responses,” analogous to “providing regulators with information” to guide the stewardship of ecosystems. They picture the enlightened harnessing of yet-to-be-discovered scale-dependent rules of internet-age social dynamics as a route to fostering the emergent phenomenon of adaptive swarm intelligence.
We wish to issue an urgent warning of our own: Responding to the self-evident fulminant, rampaging pathologies of scale ravaging the planet with yet another pathology of scale will, at best, be ineffective and, at worst, counterproductive. It is the same thing that got us here. The complex international coalition they propose would be like forming a new, ultramodern weather bureau to furnish consensus recommendations to policy makers while a megahurricane is already making landfall. This conjures images of foot dragging, floor fights, and consensus building while looking for actionable “mechanistic insight” into social dynamics on the deck of the Titanic. After lucidly spotlighting the urgent scale-dependent mechanistic nature of the crisis, Bak-Coleman et al. do not propose any immediate measures to reduce scale, but rather offer that there “is reason to be hopeful that well-designed systems can promote healthy collective action at scale...” Hope is neither a strategy nor an action.
Despite lofty goals, the coalition they propose does not match the urgency or promise a rapid and collective behavioral response to the existential threats they identify. Scale reduction may be “collective,” but achieving it will have to be local, authentic, and without delay—that is, a response conforming to the “all hands on deck” swarm intelligence phenomena that are well described in eusocial species already. When faced with the potential for imminent global ruin lurking ominously in the fat tail (5) of the future distribution, the precautionary principle dictates that we should respond with now-or-never urgency. This is a simple fact. A “weather bureau” for social dynamics would certainly be a valuable, if not indispensable, institution for future generations. But there is no reason that scientists around the world, acting as individuals within their own existing social networks and spheres of influence, observing what is already obvious with their own eyes, cannot immediately create a collective chorus to send this message through every digital channel instead of waiting for a green light from above. “Urgency” is euphemistic. It is now or never.
The Bak-Coleman and Bergstrom reply to the critique:
In our PNAS article “Stewardship of global collective behavior”, we describe the breakneck pace of recent innovations in information technology. This radical transformation has transpired not through a stewarded effort to improve information quality or to further human well-being. Rather, current technologies have been developed and deployed largely for the orthogonal purpose of keeping people engaged online. We cannot expect that an information ecology organized around ad sales will promote sustainability, equity, or global health. In the face of such impediments to rational democratic action, how can we hope to overcome threats such as global warming, habitat destruction, mass extinction, war, food security, and pandemic disease? We call for a concerted transdisciplinary response, analogous to other crisis disciplines such as conservation ecology and climate science.
In their letter, Cheong and Jones share our vision of the problem—but they express frustration at the absence of an immediately actionable solution to the enormity of challenges that we describe. They assert “swarm intelligence begins now or never” and advocate local, authentic, and immediate “scale reduction.” It’s an appealing thought: Let us counter pathologies of scale by somehow reversing course.
But it’s not clear what this would entail by way of practical, safe, ethical, and effective intervention. Have there ever been successful, voluntary, large-scale reductions in the scale of any aspect of human social life?
Nor is there reason to believe that an arbitrary, hasty, and heuristically decided large-scale restructuring of our social networks would reduce the long tail of existential risk. Rather, rapid shocks to complex systems are a canonical source of cascading failure. Moving fast and breaking things got us here. We can’t expect it to get us out.
Nor do we share the authors’ optimism about what scientists can accomplish with “a collective chorus … through every digital channel”. It is difficult to envision a louder, more vehement, and more cohesive scientific response than that to the COVID-19 pandemic. Yet this unified call for basic public health measures—grounded in centuries of scientific knowledge—nonetheless failed to mobilize political leadership and popular opinion.
Our views do align when it comes to the “now-or-never urgency” that Cheong and Jones highlight. Indeed, this is a key feature of a crisis discipline: We must act without delay to steer a complex system—while still lacking a complete understanding of how that system operates.
As scholars, our job is to call attention to underappreciated threats and to provide the knowledge base for informed decision-making. Academics do not—and should not—engage in large-scale social engineering. Our grounded view of what science can and should do in a crisis must not be mistaken for lassitude or unconcern. Worldwide, the unprecedented restructuring of human communication is having an enormous impact on issues of social choice, often to our detriment. Our paper is intended to raise the alarm. Providing the definitive solution will be a task for a much broader community of scientists, policy makers, technologists, ethicists, and other voices from around the globe.