Monday, September 27, 2021

Models of how political polarization happens

I want to recommend the article "Modeling the power of polarization" by Waldrop in the Sept. 14th PNAS (open source). I pass on just a few fragments:
There are two kinds of polarization that the media and the public often get confused... One type is issue polarization: “how much people disagree on policies like ‘What should be the tax rates?’, or ‘What should be the laws to regulate guns?’.” Those divisions have been widening of late. But they aren’t nearly as incendiary as social or “affective” polarization, which is about anger, distrust, resentment, tribal identity, and mutual loathing (see Figure, click to enlarge).

Figure Legend - Recent years have seen a marked rise in “affective” polarization, a feeling of mutual dislike and mistrust between the two sides. The trend is illustrated in data from the American National Election Survey: People's feeling of warmth toward members of their own party (green) has held steady since 1980, whereas their feelings toward members of the other party (purple) have dropped. The difference (black) is a measure of affective polarization.

[There are] ...at least four basic strategies for studying any form of polarization...The classic method is observation: using surveys and historical data to track how polarization has increased or decreased over time and which issues have been the most divisive...A second, newer strategy is to analyze the tsunami of data now available from the Internet...very useful for studying things that you cannot learn from a survey...like exactly who listens to whom and how ideas spread through the resulting social network like a contagion...Then there is the experimental approach: watching how polarization develops among volunteers in a laboratory setting. These experiments allow you to control the conditions, separate the signal from the noise, and tease out what’s cause and what’s effect...finally...models in the form of mathematical equations or computer simulations can help researchers explore the sometimes surprising outcomes of simple starting conditions or assumptions.
Several different kinds of modeling work are described in the article. Here is just the first:
Axelrod, a political scientist at the University of Michigan in Ann Arbor, "wasn't interested in the left-to-right kind of differences, so I treated ‘culture’ simply as a list of arbitrary features that were observable, like ‘What kind of hat do you wear?’ or ‘What ethnicity are you?’” Next, Axelrod modeled people as independent snippets of code, or “agents,” that could move around a simulated landscape, and gave each agent some initial set of cultural features. Then he set them to interacting with their neighbors according to two simple rules. First, the more items of culture agents share, the more likely they are to interact. And second, if agents do interact, they adopt some feature of the agent they’re interacting with...In sum, says Axelrod, the model was nothing but assimilation plus homophily: “Like gravity, it's all pulling together, right? There's nothing but attraction.” Yet the result wasn’t anything like global consensus. Instead, says Axelrod, the model consistently locked itself into a patchwork resembling the multiple language regions of Europe—or those filter bubbles on Facebook. “It’s what I call local convergence and global polarization,” he says: Cultures do indeed tend toward consensus within a finite region. But at the boundaries, the differences eventually become so stark that the agents on either side quit interacting at all. “So they never talk to each other again,” says Axelrod, “and that's why it freezes.”
Subsequent models take on emotions, show the critical role played by negative emotions, and show how groups tend to split into two cliques. The last section of the article discusses interventions to reduce polarization.

Friday, September 24, 2021

Asymptomatic infection is the pandemic’s dark matter

Fisman and Tuite do a commentary on the article by Sah et al. (open source) that includes a great graphic showing how estimated asymptomatic COVID can be biased in two different ways. I pass on first the graphic and its explanation, and then the Sah et al. significance statement. The bottom line of their meta-analysis is that more than one-third of infections are truly asymptomatic, with greater asymptomaticity in children compared with the elderly:
The... authors address two important biases in the study of asymptomatic infection in their study and note that failure to address these biases distorts estimates of asymptomaticity. The first bias is an ascertainment effect associated with studies including symptomatic index cases in their estimates. The second bias is introduced when studies capture populations of infected individuals at a single time point, which means that presymptomatic individuals (symptomatic cases whose latent period has ended but who have not yet entered the symptomatic stage) are misclassified as asymptomatic. In their review, the authors find that failure to adjust for these biases results in a predictable underestimation of the frequency of asymptomatic infection in the former case, and overestimation of asymptomaticity in the latter.
These biases, and their effects, are described in Fig. 1 (click to enlarge). The circles at the left-hand side of the figure make up a hypothetical population of infected individuals, with a true prevalence of asymptomatic infection (blue circles) of around 33%. If this population attracts notice as a result of an outbreak with notable illness, we may be more likely to sample symptomatic index cases, creating sample A. By contrast, if we are able to sample the population systematically, and obtain a representative sample of infectives, we will create sample B. If we ascertain the prevalence of symptoms at a single point in time, we will misclassify presymptomatic individuals (diagonally shaded circles) as asymptomatic. This will lead to overestimation of the prevalence of asymptomatic infection. In the diagram, 4/9 (44%) of the sample are “asymptomatic” at the first time point in sample A, while 6/9 (67%) are “asymptomatic” in sample B; both samples provide an overestimate of the true probability of asymptomatic infection. If we allow time to pass so that presymptomatic individuals become symptomatic, the probability of asymptomatic infection in sample A drops to 1/9 (11%), a marked underestimate. However, in sample B, the probability declines to 3/9 (33%), which reflects the true underlying probability of asymptomatic infection in the source population.
The Sah et al. significance statement:
Asymptomatic infections have been widely reported for COVID-19. However, many studies do not distinguish between the presymptomatic stage and truly asymptomatic infections. We conducted a systematic review and meta-analysis of COVID-19 literature reporting laboratory-confirmed infections to determine the burden of asymptomatic infections and removed index cases from our calculations to avoid conflation. By analyzing over 350 papers, we estimated that more than one-third of infections are truly asymptomatic. We found evidence of greater asymptomaticity in children compared with the elderly, and lower asymptomaticity among cases with comorbidities compared to cases with no underlying medical conditions. Greater asymptomaticity at younger ages suggests that heightened vigilance is needed among these individuals, to prevent spillover into the broader community.

Wednesday, September 22, 2021

Is self awareness a mirage?

David Brooks does a brief psychological essay - a sequel to one described in MindBlog's Sept. 10 post.
One of the most unsettling findings of modern psychology is that we often don’t know why we do what we do...We have a conscious self, of course, the voice in our head, but this conscious self has little access to the parts of the brain that are the actual sources of judgment, problem-solving and emotion. We know what we’re feeling, just not how and why we got there...we also don’t want to admit how little we know about ourselves, so we make up some story, or confabulation.
Mary Pipher, the legendary therapist and author of “Reviving Ophelia” ...prefers “what, when, where and how” questions: When do you notice feelings of inferiority? Basically, she wants clients to become closer observers of their own behavior.....Maybe the best way to see yourself is to get out of the deceptive rumination spirals of your own self-consciousness and to think about yourself in the third person...Dan McAdams, the Northwestern scholar who specializes in how people tell their life stories...doubts that we can ever really know why we do anything, so we are compelled to fall back on narratives or what he calls “personal myths.”...some stories are better than others. Stories that are closer to “what really happened” are more reliable than ones that are distorted by self-flattery and self-affirmation... Americans, McAdams has found, tend to tell redemption stories...I was rising, I faltered, I came back better.
Lori Gottlieb, the author of “Maybe You Should Talk to Someone.” She also sees therapy as a form of story-editing. But she is much more optimistic that we can actually get down to the sources of our behavior...You have to understand the “why,” so you can recognize the behavior when it’s happening again and address what’s causing you to behave as you do.
Epley, the "Mindwise" author, stressed that we can attain true wisdom and pretty good self-awareness by looking at behavior and reality in the face to create more accurate narratives, and highlighted the importance of humility in life... recognizing that we don’t have privileged access to our minds, toneing down our self-confidence and realizing don’t know other people as well as we think we do.”

Monday, September 20, 2021

Secure human attachment can promote support for climate change mitigation

From Misa et al.

Significance

Attachment theory focuses on the primal form of emotional bonding between humans. Attachment is conceptualized as an innate behavioral system aimed at safeguarding against potential threats by assuring proximity to caring and supportive others. When individuals feel securely attached (thus feeling less threatened in most situations), the activation of the caregiving behavioral system (concern for others) is facilitated. With this research, we show that priming attachment security influences how much people care about and accept climate change via an increased empathy for humanity. Furthermore, we demonstrate that this activation bypasses the resistance of politically conservative individuals to mitigate climate change. Overall, we show that attachment security–based stimuli can inform intervention and policymaking strategies to help fight climate change.
Abstract
Attachment theory is an ethological approach to the development of durable, affective ties between humans. We propose that secure attachment is crucial for understanding climate change mitigation, because the latter is inherently a communal phenomenon resulting from joint action and requiring collective behavioral change. Here, we show that priming attachment security increases acceptance (Study 1: n = 173) and perceived responsibility toward anthropogenic climate change (Study 2: n = 209) via increased empathy for others. Next, we demonstrate that priming attachment security, compared to a standard National Geographic video about climate change, increases monetary donations to a proenvironmental group in politically moderate and conservative individuals (Study 3: n = 196). Finally, through a preregistered field study conducted in the United Arab Emirates (Study 4: n = 143,558 food transactions), we show that, compared to a message related to carbon emissions, an attachment security–based message is associated with a reduction in food waste. Taken together, our work suggests that an avenue to promote climate change mitigation could be grounded in core ethological mechanisms associated with secure attachment.

Monday morning tonic - A modern folk song about your brain

Ryan Stotland, a song writer from Montreal, has pointed me to a few of his engaging pieces, and I pass on one of them to you. It rhapsodizes about what different parts of our brains do... (not to worry, if you're a regular MindBlog reader, that the facts presented are phrenological oversimplifications that are a bit out of date.) 

 

Friday, September 17, 2021

How social mindfulness and prosociality vary across the globe

From Van Doesum et al. (open source) I pass on the abstract, one figure, and a clip of the discussion: Significance
Cooperation is key to well-functioning groups and societies. Rather than addressing high-cost cooperation involving giving money or time and effort, we examine social mindfulness—a form of interpersonal benevolence that requires basic perspective-taking and is aimed at leaving choice for others. Do societies differ in social mindfulness, and if so, does it matter? Here, we find not only considerable variation across 31 nations and regions but also an association between social mindfulness and countries’ performance on environmental protection. We conclude that something as small and concrete as interpersonal benevolence can be entwined with current and future issues of global importance.
Abstract
Humans are social animals, but not everyone will be mindful of others to the same extent. Individual differences have been found, but would social mindfulness also be shaped by one’s location in the world? Expecting cross-national differences to exist, we examined if and how social mindfulness differs across countries. At little to no material cost, social mindfulness typically entails small acts of attention or kindness. Even though fairly common, such low-cost cooperation has received little empirical attention. Measuring social mindfulness across 31 samples from industrialized countries and regions (n = 8,354), we found considerable variation. Among selected country-level variables, greater social mindfulness was most strongly associated with countries’ better general performance on environmental protection. Together, our findings contribute to the literature on prosociality by targeting the kind of everyday cooperation that is more focused on communicating benevolence than on providing material benefits.  
Distribution of means for Social Mindedness (SoMi), (click to enlarge)
In the end, what best explains the general picture? Considering all findings, we suggest that SoMi may be conceptualized as a specific and effective expression of social capital, a comprehensive perspective on society with important implications for its development and functioning (30). Following one of the definitions, the economic function of social capital is to diminish the costs of formal coordination tasks by using informal social communication channels. From a relational perspective, such capital materializes through social interactions that include low-cost cooperation. Requiring no monetary or otherwise effortful investments to acknowledge, confirm, and promote high-trust social relationships, SoMi would be specifically set up to do so; the socially mindful person signals benevolence and trustworthiness. A promising connection with social capital is also suggested in the ranking of our locations: Japan, highest on the SoMi list, is traditionally known for stressing the value of social capital, and ranks 12th (of 180) on the Global Sustainable Competiveness Index social capital world index, while Indonesia, lowest on the SoMi list, ranks 70. A simple bivariate correlation without corrections learns that SoMi and social capital scores are associated at r (30) = 0.56, P = 0.002. Although quantifying social capital is difficult, this is corroborated by the relations we found between SoMi and the ensemble of variables lead by EPI and followed by economic indices (GDP, GNI, and Gini), rule of law, power distance, individual and generalized trust, and civic cooperation (tendency only), which all in their own way have been connected to presence and development of social capital. Future research could develop this.

Wednesday, September 15, 2021

Domestic dogs: Born human whisperers

Vignieri does a summary of recent work by  Bray et al. and Salomans et al. in Current Biology

 
The closest relative to dogs, “man’s best friend,” is the wolf, a wily predator that generally avoids human interaction. For decades, researchers and dog owners have wondered how the leap to domestication occurred. The main hypothesis invoked very early selection for wolves that “liked”—or least tolerated—humans, and the connection strengthened from there. However, there is still some debate about whether the degree to which dogs interact and communicate with humans is a learned trait. Two recent studies appear to close the book on this learning hypothesis. Bray et al. looked at about 400 puppies and found that at this young age and without much human interaction, they were adept at following human gestures and positively responded to high-pitched “puppy talk.” Further, there was variation in these responses with an association between relatedness and social communication skills, which supports a genetic driver. Salomons et al. compared dog and wolf puppies and found no difference in general cognitive responses, but much greater responsiveness to human gestures and eye contact, in dog puppies. Importantly, this happened even though the dog pups had received less actual human interaction than did the wolf pups. These studies confirm that dogs’ interest in communication with humans is an evolved trait unique to their lineage.

Monday, September 13, 2021

The 31st First Annual Ig Nobel Ceremony -

I pass on this Science.org summary of the virtual awards ceremony.
Musical cats, upside-down rhinos, and submarine cockroaches took the gold last night at the 31stst annual Ig Nobel Prize ceremony—an awards show honoring research that “makes people laugh, then think.” Although the pandemic kept the ceremony virtual for a second year, organizers made the best of the format. Nobel laureates, including Frances Arnold (chemistry, 2018) and Eric Maskin (economics, 2007), “handed” awardees their prizes—self-assembled 3D paper gears printed with pictures of teeth. This year’s theme was “engineering.”
The biology prize—one of 10 awards—went to a series of studies on the purrs, trills, tweedles, murmurs, meows, yowls, and other sounds cats seem to use to communicate their desires to humans. Cat vocalization researcher Susanne Schötz at Lund University has been hard at work cracking the “cat code” with her collaborators since 2011, handing the microphone to cats to analyze what felines mean when they meow.
Schötz was honored for several papers, including one on how well humans interpret cat “meowsic.” She reported that when cats want food from their owners, their sounds tend to rise in pitch at the end. If the cats are anxious about a trip to the vet, however, they drop their pitch. When she played meows for a group of 30 humans, she found they guessed the cats’ feelings from intonation alone the majority of the time. Cat owners were the best guessers, showing that when it comes to cats, practice makes purrfect.
Other prizes went to research on animals that reached for the sky and dove under the sea. The transportation prize honored researchers who determined that the best way to transport a rhinoceros by helicopter is upside down. This technique has been vital to conservationists who move large animals such as rhinos and elephants to keep them safe from poachers or maintain genetic diversity. During the ceremony, the honorees assured Nobel laureate Richard Roberts (physiology or medicine, 1993) that they’d tested the technique on themselves before trying it on rhinos. Roberts maintained that if he ever had to be transported to a safer place, “I hope not to be doing it upside down.”
The entomology prize highlighted one of the most fraught human-animal relationships: the ongoing battle between humans and cockroaches. For this prize, the awards committee dug deep into the archives for a study from 1971 titled, “A new method of cockroach control on submarines.” Retired U.S. Navy Cmdr. John Mulrennan Jr. accepted the award for developing a new technique for getting rid of cockroaches on navy submarines using a pesticide called dichlorvos after the ethylene oxide gas previously used made someone sick. “The Navy was happy at the time,” he noted in his acceptance speech, although he doesn’t know whether it still uses his technique.
Other awards included the physics prize, for an analysis of why people in crowds don’t constantly run into each other, and the kinetics prize, for a study answering why they sometimes do (the answer: cellphones). The ecology prize went to an analysis of bacteria that hitch a ride on used chewing gum, the peace prize went to a test of how effectively beards protect faces from punches (they soften the blow), and the medicine prize went to a study of whether orgasms can serve as an effective nasal decongestant. (They can, but the effects only last about 1 hour.) Winners also received a fake 10 trillion Zimbabwean dollar bill from Marc Abrahams, editor of the Annals of Improbable Research and host of the ceremony.
Dispersed throughout the night were several “24/7” talks, in which researchers gave full technical descriptions of a scientific topic in 24 seconds followed by a simple explanation in seven words. (“Coffee drinking: good, good for you … maybe!”) To round out the proceedings, scientists and opera singers performed an original three-act miniopera called A Bridge Between People. Its plot revolved around children bringing together angry adults by building tiny suspension bridges between them.
Abrahams ended the night by expressing his hope that everyone could be together in person next year, and by delivering his traditional signoff: “If you didn’t win an Ig Nobel Prize tonight—and especially if you did—better luck next year.”

Friday, September 10, 2021

You Are Not Who You Think You Are

I want to point to the NYTimes piece by polymath David Brooks that does a nice summary of several themes that have been emphasized in MindBlog posts - on the recent work of Barrett, Friston, Hoffman, Johnson, and others. He touches on several areas in which our understanding of how our minds work has been completely transformed by work and ideas over just the past 10 years. I suggest you read the whole article and click on links to the articles he references. Here are a few clips:
You may think you understand the difference between seeing something and imagining it. When you see something, it’s really there; when you imagine it, you make it up. That feels very different...It turns out, reality and imagination are completely intermixed in our brain...the separation between our inner world and the outside world is not as clear as we might like to think.
...most of seeing is making mental predictions about what you expect to see, based on experience, and then using sensory input to check and adjust your predictions. Thus, your memory profoundly influences what you see...The conversation between senses and memory produces a “controlled hallucination,” which is the closest we can get to registering reality.
...humans have come up with all sorts of concepts to describe different thinking activities: memory, perception, emotion, attention, decision-making. But now, as scientists develop greater abilities to look at the brain doing its thing, they often find that the activity they observe does not fit the neat categories our culture has created, and which we rely on to understand ourselves...Barrett of Northeastern University argues that people construct emotions and thoughts, and there is no clear distinction between them...emotions assign value to things, so they are instrumental to reason, not separate from or opposed to it.
...there is no such thing as disembodied understanding. Your neural, chemical and bodily responses are in continual conversation with one another, so both understanding and experiencing are mental and physical simultaneously...When faced with a whole person...we shouldn’t think that they can be divided into a ‘mind’ and a ‘body.
...You realize that neither the term ‘decision-making’ nor the term ‘attention’ actually corresponds to a thing in the brain...the concepts at the core of how we think about thinking need to be radically revised...neuroscientists spent a lot of time trying to figure out what region of the brain did what function. (Fear is in the amygdala!) Today they also look at the ways vast networks across the brain, body and environment work together to create comprehensive mental states. Now there is much more emphasis on how people and groups creatively construct their own realities, and live within their own constructions.

Wednesday, September 08, 2021

Ageing yields improvements as well as declines across attention and executive functions

Interesting work from Verissimo et al.:
Many but not all cognitive abilities decline during ageing. Some even improve due to lifelong experience. The critical capacities of attention and executive functions have been widely posited to decline. However, these capacities are composed of multiple components, so multifaceted ageing outcomes might be expected. Indeed, prior findings suggest that whereas certain attention/executive functions clearly decline, others do not, with hints that some might even improve. We tested ageing effects on the alerting, orienting and executive (inhibitory) networks posited by Posner and Petersen’s influential theory of attention, in a cross-sectional study of a large sample (N = 702) of participants aged 58–98. Linear and nonlinear analyses revealed that whereas the efficiency of the alerting network decreased with age, orienting and executive inhibitory efficiency increased, at least until the mid-to-late 70s. Sensitivity analyses indicated that the patterns were robust. The results suggest variability in age-related changes across attention/executive functions, with some declining while others improve.

Monday, September 06, 2021

A test of plasticity-based cognitive training in treating mild traumatic brain injury

A study from Mahncke et al. (open source) shows that using a computerized cognitive training program that I have mentioned in previous MindBlog posts (BrainHQ, Posit Science) improves cognitive function in people with mild traumatic brain injury. Here is their abstract:
Clinical practice guidelines support cognitive rehabilitation for people with a history of mild traumatic brain injury (mTBI) and cognitive impairment, but no class I randomized clinical trials have evaluated the efficacy of self-administered computerized cognitive training. The goal of this study was to evaluate the efficacy of a self-administered computerized plasticity-based cognitive training programmes in primarily military/veteran participants with a history of mTBI and cognitive impairment. A multisite randomized double-blind clinical trial of a behavioural intervention with an active control was conducted from September 2013 to February 2017 including assessments at baseline, post-training, and after a 3-month follow-up period. Participants self-administered cognitive training (experimental and active control) programmes at home, remotely supervised by a healthcare coach, with an intended training schedule of 5 days per week, 1 h per day, for 13 weeks. Participants (149 contacted, 83 intent-to-treat) were confirmed to have a history of mTBI (mean of 7.2 years post-injury) through medical history/clinician interview and persistent cognitive impairment through neuropsychological testing and/or quantitative participant reported measure. The experimental intervention was a brain plasticity-based computerized cognitive training programme targeting speed/accuracy of information processing, and the active control was composed of computer games. The primary cognitive function measure was a composite of nine standardized neuropsychological assessments, and the primary directly observed functional measure a timed instrumental activities of daily living assessment. Secondary outcome measures included participant-reported assessments of cognitive and mental health. The treatment group showed an improvement in the composite cognitive measure significantly larger than that of the active control group at both the post-training [+6.9 points, confidence interval (CI) +1.0 to +12.7, P = 0.025, d = 0.555] and the follow-up visit (+7.4 points, CI +0.6 to +14.3, P = 0.039, d = 0.591). Both large and small cognitive function improvements were seen twice as frequently in the treatment group than in the active control group. No significant between-group effects were seen on other measures, including the directly-observed functional and symptom measures. Statistically equivalent improvements in both groups were seen in depressive and cognitive symptoms.

Friday, September 03, 2021

Babbling bats

An interesting piece from Fernandez et al.:
Babbling is a production milestone in infant speech development. Evidence for babbling in nonhuman mammals is scarce, which has prevented cross-species comparisons. In this study, we investigated the conspicuous babbling behavior of Saccopteryx bilineata, a bat capable of vocal production learning. We analyzed the babbling of 20 bat pups in the field during their 3-month ontogeny and compared its features to those that characterize babbling in human infants. Our findings demonstrate that babbling in bat pups is characterized by the same eight features as babbling in human infants, including the conspicuous features reduplication and rhythmicity. These parallels in vocal ontogeny between two mammalian species offer future possibilities for comparison of cognitive and neuromolecular mechanisms and adaptive functions of babbling in bats and humans.

Wednesday, September 01, 2021

The neuroinflammation collection: a review of neuro-immune crosstalk

Irani et al. (open source) offer a compact and concise review that highlights publications in Brain over the past several years as a focal point to offer a vision of how anticipated developments in neuroinflammation are likely to impact our understanding of key elements of neurology, and lead to new treatments. They offer some nice summary graphics, and organize their presentation around several areas: 

-Prototypical autoimmune-mediated conditions

-Neurodegeneration 

-Multiple sclerosis and CNS neoplasia 

-Inflammation in cerebrovascular disease 

-Harnessing innate immune responses in the brain 

 

Monday, August 30, 2021

Two Americas

I've been trying to dial down MindBlog's mention of our current domestic turmoil and debate, but I can't resist passing on this clip from Krugman's recent piece that gives one succinct summary of our quandry:
Since the 1980s America has experienced growing regional divergence. We have become a knowledge economy driven by industries that rely on a highly educated work force, and firms in those industries, it turns out, want to be located in places where there are a lot of highly educated workers already — places like the Bay Area.
Unfortunately, most of these rising knowledge-industry hubs also severely limit housing construction; this is true even of greater New York, which is much denser than any other U.S. metropolitan area but could and should be even denser. As a result, housing prices in these metros have soared, and working-class families, instead of sharing in regional success, are being driven out.
The result is that there are now, in effect, two Americas: the America of high-tech, high-income enclaves that are unaffordable for the less affluent, and the rest of the country.
And this economic divergence goes along with political divergence, mainly because education has become a prime driver of political affiliation.
It may seem hard to believe now, but as recently as the early 2000s college graduates leaned Republican. Since then, however, highly educated voters — who have presumably been turned off by the G.O.P.’s embrace of culture wars and its growing anti-intellectualism — have become overwhelmingly Democratic, while non-college-educated whites have gone the other way.
As a result, the two Americas created by the collision of the knowledge economy and NIMBYism correspond fairly closely to the blue-red division: Democratic-voting districts have seen a big rise in incomes, while G.O.P. districts have been left behind:


 

Friday, August 27, 2021

Douthat's Guide to Finding Faith

I recommend that you read through Douthat's elegant exposition of the continuing relevance of some form of religious faith. I paste in below a few clips that particularly struck me.....
The great project of modern physics...has repeatedly confirmed the strange fittedness of our universe to human life. If science has discredited certain specific ideas about how God structured the natural world, it has also made the mathematical beauty of physical laws, as well as their seeming calibration for the emergence of life, much clearer to us than they were to people 500 years ago.
...The remarkable advances of neuroscience have only sharpened...the difficulty of figuring out how physical processes alone could create the lived reality of conscious life...So notable is the failure to discover consciousness in our dissected tissue that certain materialists, like Dennett, have fastened onto the idea that both conscious experience and selfhood must be essentially illusions...This idea, no less than the belief in a multiverse of infinite realities, requires a leap of faith. Both seem less parsimonious, less immediately reasonable, than a traditional religious assumption that mind precedes matter, as the mind of God precedes the universe — that the precise calibrations of physical reality and the irreducibility of personal experience are proof that consciousness came first.
..the God hypothesis is constantly vindicated by the comprehensibility of the universe, and the capacity of our reason to unlock its many secrets. Indeed, there’s a quietly theistic assumption to the whole scientific project. As David Bentley Hart puts it in his book “The Experience of God,” “We assume that the human mind can be a true mirror of objective reality because we assume that objective reality is already a mirror of mind.”
...when today’s evolutionary theorists go searching for a reason people believe so readily in spiritual powers and nonhuman minds, they are also making a concession to religion’s plausibility — because most of our evolved impulses and appetites correspond directly to something in reality itself...Of course, religion could be the exception: a desire with no real object, a set of experiences with no correlate outside the mind, sustained by a combination of wishful thinking, the desire of mortal creatures to believe in the imperishable and the inevitability of what debunkers of supernatural fraud sometimes call “residua,” the slice of strange events that lie outside our current scope of explanation.
...the world in 2021, no less than the world in 1521 or 321, presents considerable evidence of an originating intelligence presiding over a law-bound world well made for our minds to understand, and at the same time a panoply of spiritual forces that seem to intervene unpredictably in our existence.
That combination corresponds reasonably well to the cosmology on offer in many major world religions, from Christianity with its creator God who exists outside of space and time and its ministering angels and interceding saints, to Hinduism with its singular divinity finding embodiment in a pantheon of gods. Almost as if the old faiths had a somewhat plausible grasp on reality all along.
But wait, you might say: Given that Hinduism and Christianity are actually pretty different, maybe this attempted spell-breaking doesn’t get us very far. Postulating an uncreated divine intelligence or ultimate reality doesn’t tell us much about what God wants from us. Presupposing an active spiritual realm doesn’t prove that we should all go back to church, especially if these experiences show up cross-culturally, which means they don’t confirm any specific dogma. And you haven’t touched all the important problems with religion — what about the problem of evil? What about the way that institutional faith is used to oppress and shame people? Why not deism instead of theism, or pantheism instead of either?
These are fair questions, but this essay isn’t titled “How to Become a Presbyterian” or “How to Know Which Faith Is True.” The spell-breaking I’m offering here is a beginning, not an end. It creates an obligation without telling you how exactly to fulfill it. It opens onto further arguments, between religious traditions and within them, that aren’t easily resolved.
The difficulties of those ancient arguments — along with the challenge of dealing with religion as it’s actually embodied, in flawed people and institutions — are a big part of what keeps the spell of materialism intact. For finite and suffering creatures, religious belief offers important kinds of hope and consolation. But unbelief has its own comforts: It takes a whole vast zone of ideas and arguments, practices and demands, supernatural perils and metaphysical complexities, and whispers, well, at least you don’t have to spend time thinking about that.
But actually you do. So if you are standing uncertainly on the threshold of whatever faith tradition you feel closest to, you don’t have to heed the inner voice insisting that it’s necessarily more reasonable and sensible and modern to take a step backward. You can recognize instead that reality is probably not as materialism describes it, and take up the obligation of a serious human being preparing for life and death alike — to move forward, to step through.

Wednesday, August 25, 2021

Well-being of the aging brain - from the Univ.of Wisc. Center for Healty Minds

I am a supporter of the Center for Healthy Minds  at the University of Wisconsin, Madison, which was established and is lead by one of my former colleagues, Richie Davidson, The Center has recently released the transcript  (PDF here) of an August 16 live online seminar titled "The Aging Brain: Developing Well-Being for your future," that features three researchers talking about their work on aging. Melissa Rosenkranz describes work on bi-directional mind-brain-immune pathways through which emotion and inflammation are mutually influential, Ozioma Okokwe's work is on factors influencing resilience to Alzheimer's disease, and Stacey Schaefer, who leads the neuroscience project of the midlife in the US study (MIDUS), describes work on the time course and duration of emotional response and how they relate to long term cognitive and health outcomes. At the end of the transcript graphics used in the presentations as well as sources mentioned in the lectures are given. I am finding a number of the sources quite interesting, so I paste them in below:

OPPS!  NOTE ADDED.  A READER REPORTS THE LINKS BELOW DID NOT SURVIVE MY CUT AND PASTE.  SORRY ABOUT THAT....BUT, IT YOU CLICK THE "PDF HERE" LINK ABOVE, TO GET THE TRANSCRIPT OF THE SESSION, YOU GET THE REFERENCES AT THE END AND THOSE LINKS DO WORK.    

LINKS MENTIONED:

Learn more about MIDUS here: http://midus.wisc.edu/index.php
A paper on the topic of Dementia linked to Rumination is nicely summarized here: Rumination and Worry

Linked to Increased Dementia Risk

Here's a link from the American Federation for Aging Research (AFAR) to webinars related to aging on sleep, exercise, nutrition, gaming, cognition, as well as COVID: https://www.afar.org/afar-webinars

See the long list of aging-related links on this page from the Institute on Aging:

https://aging.wisc.edu/resources/

Here’s the paper about purpose in life, loneliness, and protective health behaviors during the COVID-19 pandemic: https://academic.oup.com/gerontologist/article/61

The paper on the exercise study can be found here: https://pubmed.ncbi.nlm.nih.gov/31970... The NIAWebsite for Physical Activity can be accessed at this link: https://go4life.nia.nih.gov

Find small moments of delight to boost happiness. Check out the Joy Generator:

https://apps.npr.org/joy-generator
Visit https://hminnovations.org/meditation-app or explore Healthy Minds Innovations other well-being

tools at https://hminnovations.org/well-being-...
Here's information about the MIND diet that Dr. Schaefer referenced: (Mediterranean-DASH Intervention

for Neurodegenerative Delay diet): https://www.rush.edu/news/brain-healt...
This link has information about aging and sleep: https://www.sleepfoundation.org/aging...

Monday, August 23, 2021

Research experiences and social justice

In the Editor's Choice section of the July 23 issue of Science Magazine Melissa McCarntney does a brief description of a biomedical research training program rooted in Critical Race Theory (CRT). Trying to overcome my initial knee jerk response of 'this is total Woke bullshit' (after all, I am an old school college professor) I forced myself to actually read through the article in question - a really tough slog through a long jargon laden (intersectionality, etc) slew of words - to find a few sentences that gave some notion of what the experimenters actually did. Here is a clip from the Camacho et al. paper:
In summer training and throughout the academic year, training modules and discussions on racism, sexism, and other forms of discrimination occur in BUILD PODER. We introduce students to the importance of cultural diversity in the sciences, implicit biases and prejudice in the forms of gender and racial microaggressions (Solórzano et al., 2000) and macroaggressions (Jones et al., 2010; van Ryn et al., 2015), impostor phenomenon (Cokley et al., 2013, 2015; Peteet et al., 2015), and stereotype threat (Steele, 1995, 1997; Jones et al., 2010). Students also learn strategies to deal with, overcome, and cope with these potential barriers and prejudices. Each module and workshop contains references to literature that highlights the intersection between racism and the sciences (e.g., van Ryn et al., 2015). These modules also include discussions about recognizing and highlighting what students can do when experiencing a micro-aggression.
This makes good sense, and appears to have helped the "URM" (underrepresented racial minority students). Here is McCartney's summary (the link to the article gets you its longer abstract):
Past diversity training initiatives have not yet led to equity in the STEM field. Camacho et al. propose a new tool to help approach that goal. BUILD PODER is an undergraduate biomedical research training program rooted in Critical Race Theory (CRT). The program unites students and faculty around biomedical research questions while contextualizing these questions around issues of social justice. The integration of research and social justice allows for a curriculum directed at transparency, respect, and correcting the historical abuses in science. Analysis of outcomes among a sample of undergraduate Latinx seniors revealed that BUILD PODER participants reported higher levels of science personal identity and science social identity upon graduation, demonstrating a positive effect of CRT-informed research experiences on Latinx students' science identity.

Friday, August 20, 2021

YouTube algorithms do not appear to drive attention to radical content.

From Hosseinmardi et al.;  

Significance

Daily share of news consumption on YouTube, a social media platform with more than 2 billion monthly users, has increased in the last few years. Constructing a large dataset of users’ trajectories across the full political spectrum during 2016–2019, we identify several distinct communities of news consumers, including “far-right” and “anti-woke.” Far right is small and not increasing in size over the observation period, while anti-woke is growing, and both grow in consumption per user. We find little evidence that the YouTube recommendation algorithm is driving attention to this content. Our results indicate that trends in video-based political news consumption are determined by a complicated combination of user preferences, platform features, and the supply-and-demand dynamics of the broader web.
Abstract
Although it is under-studied relative to other social media platforms, YouTube is arguably the largest and most engaging online media consumption platform in the world. Recently, YouTube’s scale has fueled concerns that YouTube users are being radicalized via a combination of biased recommendations and ostensibly apolitical “anti-woke” channels, both of which have been claimed to direct attention to radical political content. Here we test this hypothesis using a representative panel of more than 300,000 Americans and their individual-level browsing behavior, on and off YouTube, from January 2016 through December 2019. Using a labeled set of political news channels, we find that news consumption on YouTube is dominated by mainstream and largely centrist sources. Consumers of far-right content, while more engaged than average, represent a small and stable percentage of news consumers. However, consumption of “anti-woke” content, defined in terms of its opposition to progressive intellectual and political agendas, grew steadily in popularity and is correlated with consumption of far-right content off-platform. We find no evidence that engagement with far-right content is caused by YouTube recommendations systematically, nor do we find clear evidence that anti-woke channels serve as a gateway to the far right. Rather, consumption of political content on YouTube appears to reflect individual preferences that extend across the web as a whole.

Wednesday, August 18, 2021

Castration delays aging

I pass on this nugget by Beverly Purnell in the Editor's Choice section of this week's Science Magazine noting an interesting paper by Sugrue et al. First her summary, then the abstract of the Sugrue et al. paper.  

The summary:

As we age, our genetic material changes, not only through DNA mutation but also by epigenetic modification. Indeed, chronological age can be estimated based on analysis of DNA methylation. Male and female mammals display different average life spans, and a role for sex hormones is expected in this effect. Sugrue et al. established an epigenetic clock in sheep by examining methylated DNA in samples from blood and ears. They show that castration extends an animal's life span and feminizes the epigenome at specific androgen-regulated loci during aging.
The Abstract:
In mammals, females generally live longer than males. Nevertheless, the mechanisms underpinning sex-dependent longevity are currently unclear. Epigenetic clocks are powerful biological biomarkers capable of precisely estimating chronological age and identifying novel factors influencing the aging rate using only DNA methylation data. In this study, we developed the first epigenetic clock for domesticated sheep (Ovis aries), which can predict chronological age with a median absolute error of 5.1 months. We have discovered that castrated male sheep have a decelerated aging rate compared to intact males, mediated at least in part by the removal of androgens. Furthermore, we identified several androgen-sensitive CpG dinucleotides that become progressively hypomethylated with age in intact males, but remain stable in castrated males and females. Comparable sex-specific methylation differences in MKLN1 also exist in bat skin and a range of mouse tissues that have high androgen receptor expression, indicating that it may drive androgen-dependent hypomethylation in divergent mammalian species. In characterizing these sites, we identify biologically plausible mechanisms explaining how androgens drive male-accelerated aging.

Monday, August 16, 2021

What is our brain's spontaneous activity for?

Continuing in MindBlog's recent thread on the predictive brain (see here and here), I pass on highlights of an opinion piece by Pezzulo et al., who suggest that all that background brain noise has a very specific purpose - figuring out what to expect next:
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.

Friday, August 13, 2021

The connections between two brain regions that are required for consciousness are regulated by dopamine.

Important work from Spindler et al.:  

Significance

Understanding the neural bases of consciousness is of basic scientific and clinical importance. Human neuroimaging has established that a network of interconnected brain regions known as the default mode network disintegrates in anesthesia and after brain damage that causes disorders of consciousness. However, the neurochemical underpinnings of this network change remain largely unknown. Motivated by preclinical animal work and clinical observations, we found that across pharmacological (sedation) and pathological (disorders of consciousness) consciousness perturbation, the dopaminergic source nucleus, the ventral tegmental area, disconnects from the main nodes of the default mode network. As the severity of this dopaminergic disconnection was associated with default mode network disintegration, we propose that dopaminergic modulation may be a central mechanism for consciousness maintenance.
Abstract
Clinical research into consciousness has long focused on cortical macroscopic networks and their disruption in pathological or pharmacological consciousness perturbation. Despite demonstrating diagnostic utility in disorders of consciousness (DoC) and monitoring anesthetic depth, these cortico-centric approaches have been unable to characterize which neurochemical systems may underpin consciousness alterations. Instead, preclinical experiments have long implicated the dopaminergic ventral tegmental area (VTA) in the brainstem. Despite dopaminergic agonist efficacy in DoC patients equally pointing to dopamine, the VTA has not been studied in human perturbed consciousness. To bridge this translational gap between preclinical subcortical and clinical cortico-centric perspectives, we assessed functional connectivity changes of a histologically characterized VTA using functional MRI recordings of pharmacologically (propofol sedation) and pathologically perturbed consciousness (DoC patients). Both cohorts demonstrated VTA disconnection from the precuneus and posterior cingulate (PCu/PCC), a main default mode network node widely implicated in consciousness. Strikingly, the stronger VTA–PCu/PCC connectivity was, the more the PCu/PCC functional connectome resembled its awake configuration, suggesting a possible neuromodulatory relationship. VTA-PCu/PCC connectivity increased toward healthy control levels only in DoC patients who behaviorally improved at follow-up assessment. To test whether VTA–PCu/PCC connectivity can be affected by a dopaminergic agonist, we demonstrated in a separate set of traumatic brain injury patients without DoC that methylphenidate significantly increased this connectivity. Together, our results characterize an in vivo dopaminergic connectivity deficit common to reversible and chronic consciousness perturbation. This noninvasive assessment of the dopaminergic system bridges preclinical and clinical work, associating dopaminergic VTA function with macroscopic network alterations, thereby elucidating a critical aspect of brainstem–cortical interplay for consciousness.

Wednesday, August 11, 2021

How the insiders win - Philanthropy, advocacy, and profit.

From Bertrand et al., a study showing how U.S. Federal rulemaking based on considering "independent viewpoints" is corrupted:
Information is central to designing effective policy, and policymakers often rely on competing interests to separate useful from biased information. We show how this logic of virtuous competition can break down, using a new and comprehensive dataset on U.S. federal regulatory rulemaking for 2003–2016. For-profit corporations and nonprofit entities are active in the rulemaking process and are arguably expected to provide independent viewpoints. Policymakers, however, may not be fully aware of the financial ties between some firms and nonprofits – grants that are legal and tax-exempt, but hard to trace. We document three patterns which suggest that these grants may distort policy. First, we show that, shortly after a firm donates to a nonprofit, that nonprofit is more likely to comment on rules on which the firm has also commented. Second, when a firm comments on a rule, the comments by nonprofits that recently received grants from the firm’s foundation are systematically closer in content to the firm’s own comments, relative to comments submitted by other nonprofits. Third, the final rule’s discussion by a regulator is more similar to the firm’s comments on that rule when the firm’s recent grantees also commented on it.

Monday, August 09, 2021

Electromagnetic radiation in the wireless signal range increases wakefulness in mice

Liu et al. (open source) find that electromagnetic radiation (EMR) in the wireless signal range used by our cell phones, laptops, and Wi-Fi routers can increase wakefulness in mice, but only if the signal is pulsed and at much higher levels than are present in our homes.  

Significance

The steady increase of electromagnetic radiation (EMR) in the environment, particularly the wireless signal, causes serious public concern over its potential negative impact on health. However, it is challenging to examine such impact on human subjects due to associated complex issues. In this study, we establish an experimental system for the investigation of EMR impact on mice. Using this system, we uncovered a causal relationship between 2.4-GHz EMR modulated by 100-Hz square pulses and increased wakefulness in mice. This result identifies sleep alteration as a potential consequence of exposure to excessive wireless signals.
Abstract
Electromagnetic radiation (EMR) in the environment has increased sharply in recent decades. The effect of environmental EMR on living organisms remains poorly characterized. Here, we report the impact of wireless-range EMR on the sleep architecture of mouse. Prolonged exposure to 2.4-GHz EMR modulated by 100-Hz square pulses at a nonthermal output level results in markedly increased time of wakefulness in mice. These mice display corresponding decreased time of nonrapid eye movement (NREM) and rapid eye movement (REM). In contrast, prolonged exposure to unmodulated 2.4-GHz EMR at the same time-averaged output level has little impact on mouse sleep. These observations identify alteration of sleep architecture in mice as a specific physiological response to prolonged wireless-range EMR exposure.
The final two paragraphs of the paper make clear that the effects on mouse sleep require much higher power densities for the 2.4-GHz EMR signals than are emitted by smartphones, laptops, or Wi-Fi routers.
....the average power density at close proximity is about 0.037 W/m2 for a smartphone, 0.013 W/m2 for a laptop, and 0.13 W/m2 near the Wi-Fi router (1). These values are considerably lower than the time- and whole-body–averaged general public exposure limit of 10 W/m2 or occupational exposure limit of 50 W/m2 for 2–300 GHz suggested by International Commission on Non-Ionizing Radiation Protection (43). In our experiments, the measured spatial averaged power density for Conti8W is 36.80 ± 0.92 W/m2. Pulse64W is expected to have the same power density. Importantly, the effective EMR dose for inducing a biological response in mice is likely to be different from that in humans. Therefore, the relatively high EMR dose of the Pulse64W regimen that causes increased wakefulness in mice could be markedly reduced in humans. An epidemiological survey among those who work under either very high or very low doses of wireless radiation may reveal some clues.
In this study, 2.4-GHz EMR is modulated by 100-Hz square pulses, which have sharp edges and thus might have some unanticipated impact on neural activity in the brain. Additional experiments should be performed to examine whether other modulation functions such as sinusoidal modulation can induce similar increase of wakefulness in mice. In addition, other modulation frequencies such as 10 and 1,000 Hz should be investigated to answer the question of whether increased wakefulness is specific to certain modulation frequencies. Finally, both the intensity and the frequency of the carrier EMR (2.4 GHz in this study) should be scrutinized.

Friday, August 06, 2021

Seeing others react to threats triggers our own internal threat responses.

From Haaker et al. (open source)

Significance

Social transmission of threat information by observation is effective in humans and other animals. However, it is unknown if such observation of others’ reacting to threats can retrieve memories that have been previously learned through direct, firsthand aversive experiences. Here, we show concordantly in humans and rats that observing a conspecific’s reactions to a threat is sufficient to recover associative memories of direct, firsthand aversive experiences, measured as conditioned threat responses (physiological responses and defensive behavior) in the observer. The reinstatement of threat responses by observation of others is specific to the context that is observed as being dangerous. Our findings provide cross-species evidence that observation of others’ threat reactions can recover associative memories of direct, firsthand aversive experiences.
Abstract
Information about dangers can spread effectively by observation of others’ threat responses. Yet, it is unclear if such observational threat information interacts with associative memories that are shaped by the individual’s direct, firsthand experiences. Here, we show in humans and rats that the mere observation of a conspecific’s threat reactions reinstates previously learned and extinguished threat responses in the observer. In two experiments, human participants displayed elevated physiological responses to threat-conditioned cues after observational reinstatement in a context-specific manner. The elevation of physiological responses (arousal) was further specific to the context that was observed as dangerous. An analogous experiment in rats provided converging results by demonstrating reinstatement of defensive behavior after observing another rat’s threat reactions. Taken together, our findings provide cross-species evidence that observation of others’ threat reactions can recover associations previously shaped by direct, firsthand aversive experiences. Our study offers a perspective on how retrieval of threat memories draws from associative mechanisms that might underlie both observations of others’ and firsthand experiences.

Wednesday, August 04, 2021

Historical language records reveal societal depression and anxiety in past two decades higher than during 20th century.

Fascinating work from Bollen et al. (open source):  

Significance

Can entire societies become more or less depressed over time? Here, we look for the historical traces of cognitive distortions, thinking patterns that are strongly associated with internalizing disorders such as depression and anxiety, in millions of books published over the course of the last two centuries in English, Spanish, and German. We find a pronounced “hockey stick” pattern: Over the past two decades the textual analogs of cognitive distortions surged well above historical levels, including those of World War I and II, after declining or stabilizing for most of the 20th century. Our results point to the possibility that recent socioeconomic changes, new technology, and social media are associated with a surge of cognitive distortions.
Abstract
Individuals with depression are prone to maladaptive patterns of thinking, known as cognitive distortions, whereby they think about themselves, the world, and the future in overly negative and inaccurate ways. These distortions are associated with marked changes in an individual’s mood, behavior, and language. We hypothesize that societies can undergo similar changes in their collective psychology that are reflected in historical records of language use. Here, we investigate the prevalence of textual markers of cognitive distortions in over 14 million books for the past 125 y and observe a surge of their prevalence since the 1980s, to levels exceeding those of the Great Depression and both World Wars. This pattern does not seem to be driven by changes in word meaning, publishing and writing standards, or the Google Books sample. Our results suggest a recent societal shift toward language associated with cognitive distortions and internalizing disorders.

Monday, August 02, 2021

Our gut microbiome pattern reflects healthy aging and survival

Interesting analysis by Wilmanski et al.:
The gut microbiome has important effects on human health, yet its importance in human ageing remains unclear. In the present study, we demonstrate that, starting in mid-to-late adulthood, gut microbiomes become increasingly unique to individuals with age. We leverage three independent cohorts comprising over 9,000 individuals and find that compositional uniqueness is strongly associated with microbially produced amino acid derivatives circulating in the bloodstream. In older age (over ~80 years), healthy individuals show continued microbial drift towards a unique compositional state, whereas this drift is absent in less healthy individuals. The identified microbiome pattern of healthy ageing is characterized by a depletion of core genera found across most humans, primarily Bacteroides. Retaining a high Bacteroides dominance into older age, or having a low gut microbiome uniqueness measure, predicts decreased survival in a 4-year follow-up. Our analysis identifies increasing compositional uniqueness of the gut microbiome as a component of healthy ageing, which is characterized by distinct microbial metabolic outputs in the blood.

Friday, July 30, 2021

How our brain cortex changes in the transition from childhood to adolescence.

This open source article from Dong et al. has some excellent summary graphics:  

Significance

Here, we describe age-dependent shifts in the macroscale organization of cortex in childhood and adolescence. The characterization of functional connectivity patterns in children revealed an overarching organizational framework anchored within the unimodal cortex, between somatosensory/motor and visual regions. Conversely, in adolescents, we observed a transition into an adult-like gradient, situating the default network at the opposite end of a spectrum from primary somatosensory/motor regions. This spatial framework emerged gradually with age, reaching a sharp inflection point at the transition from childhood to adolescence. These data reveal a developmental change from a functional motif first dominated by the distinction between sensory and motor systems and then balanced through interactions with later-maturing aspects of association cortex that support more abstract cognitive functions.
Abstract
The transition from childhood to adolescence is marked by pronounced shifts in brain structure and function that coincide with the development of physical, cognitive, and social abilities. Prior work in adult populations has characterized the topographical organization of the cortex, revealing macroscale functional gradients that extend from unimodal (somatosensory/motor and visual) regions through the cortical association areas that underpin complex cognition in humans. However, the presence of these core functional gradients across development as well as their maturational course have yet to be established. Here, leveraging 378 resting-state functional MRI scans from 190 healthy individuals aged 6 to 17 y old, we demonstrate that the transition from childhood to adolescence is reflected in the gradual maturation of gradient patterns across the cortical sheet. In children, the overarching organizational gradient is anchored within the unimodal cortex, between somatosensory/motor and visual territories. Conversely, in adolescence, the principal gradient of connectivity transitions into an adult-like spatial framework, with the default network at the opposite end of a spectrum from primary sensory and motor regions. The observed gradient transitions are gradually refined with age, reaching a sharp inflection point in 13 and 14 y olds. Functional maturation was nonuniformly distributed across cortical networks. Unimodal networks reached their mature positions early in development, while association regions, in particular the medial prefrontal cortex, reached a later peak during adolescence. These data reveal age-dependent changes in the macroscale organization of the cortex and suggest the scheduled maturation of functional gradient patterns may be critically important for understanding how cognitive and behavioral capabilities are refined across development.

Wednesday, July 28, 2021

Graphic depictions of an integrative model of mind

To hopefully enhance the chance that you will pay attention to the creative and seminal thinking in the open source Laukkonen and Slagter review article whose abstract I passed on in my July 21 post,  I now pass on their striking concluding statement and then  two graphics whose legends summarize the main ideas presented. I think this work offers a plausible and appealing integration of neuroscience and meditative traditions.  

We have taken on the daunting task of providing a theory for understanding the effects of meditation within the predictive processing framework. Contemplative science is a young field and predictive processing is a new theory, although both have roots going much farther back. All theories are subject to change, but perhaps particularly so for such new domains of enquiry. Nevertheless, we think the conditions are suitable for a more overarching theory that may also thwart further siloing and fragmentation of scientific research, as has been commonplace among the mind-sciences. A strength of our framework is its simplicity: Being in the here and now reduces predictive processing. And yet, this basic idea can explain how each meditation technique uniquely deconstructs the minds tendency to project the past onto the present, how certain insights may arise, the nature of hierarchical self-processing, and the plasticity of the human mind. There is scope here, we think, to eventually reveal what makes a meditator an expert, why meditation has such broad clinical effects, and how we might begin mitigating some of the negative consequences of meditation. Last but not least, our framework seems to bring ancient Eastern and modern scientific ideas closer together, showing how the notion of conditioned experience in Buddhism aligns with the notion of the experience-dependent predictive brain.

Fig. 1. Here we use the Pythagoras Tree to provide an intuitive illustration of how organisms represent the world with increasing counterfactual depth or abstraction. The tree is constructed using squares that are scaled down by the square root of 2 divided by 2 and placed such that the corners of the squares meet and form a triangle between them, recursively. Analogously, the brain constructs experience from temporally precise and unimodal models of present-moment sensory representations and input (e.g., pixels on a screen), into ever more abstract, transmodal, and temporally deep models (e.g., a theory paper). Meditation brings one increasingly into the present moment, thus reducing the tendency to conceptualize away from the here and now, akin to observing the pixels rather than the words. This reduction of conceptualization ought to also have profound effects on the sense of self, which also relies on abstract model building, and ultimately is said to reveal an underlying seemingly “unconditioned” state of consciousness as such (like the white background underlying the pixels).
 

Fig. 2. In this schematic we illustrate two aspects of the many-to-(n)one model. The first and most foundational proposal is that meditation gradually flattens the predictive hierarchy or ‘prunes the counterfactual tree’, by bringing the meditator into the here and now, illustrated in the left figure. Thus, meditative depth is defined by the extent that the organism is not constructing temporally thick predictions. In the right figure, we dissect the predictive hierarchy into three broad levels. We propose that thinking (and therefore the narrative self [NS]) sits at the top of the predictive hierarchy (Carhart-Harris and Friston, 2010, 2019). Sensing and perceiving and therefore the embodied experiencing self [ES] sits below it (Gallagher, 2000; Seth, 2013). Finally, a basal form of self-hood characterized by the subject-object [S/O] duality sits at the earliest level. FA brings the practitioner out of the narrative self and into a more experiencing and embodied mode of being. Then, through dereification from present moment experience (including bodily sensations) OM brings the practitioner more into a state where contents of experience are treated equally, and one is able to experience non-judgmentally (sensing without appraisal), but even in very advanced states, a subject-object duality remains. During OM, certain epistemic discoveries or insights about the nature and behavior of generative models may occur. Finally, through ND practices the subject-object distinction may fall away and the background or “groundless ground” of all experience—awareness itself—can be uncovered. Another way to characterize this process is as follows: FA employs regular (conditional) attention to an object of sensing, OM employs bare (unconditional) attention, and ND practice employs reflexive awareness that permits the non-dual witnessing of the subject-object dichotomy and finally pure or non-dual awareness by releasing attention altogether.

 

 

Monday, July 26, 2021

Stable individual differences in infants’ responses to violations of intuitive physics

Interesting observations by Perez and Feigenson:
Infants look longer at impossible or unlikely events than at possible events. While these responses to expectancy violations have been critical for understanding early cognition, interpreting them is challenging because infants’ responses are highly variable. This variability has been treated as an unavoidable nuisance inherent to infant research. Here we asked whether the variability contains signal in addition to noise: namely, whether some infants show consistently stronger responses to expectancy violations than others. Infants watched two unrelated physical events 6 mo apart; these events culminated in either an impossible or an expected outcome. We found that infants who exhibited the strongest looking response to an impossible event at 11 mo also exhibited the strongest response to an entirely different impossible event at 17 mo. Furthermore, violation-of-expectation responses in infancy predicted children’s explanation-based curiosity at 3 y old. In contrast, there was no longitudinal relation between infants’ responses to events with expected outcomes at 11 and 17 mo, nor any link with later curiosity; hence, infants’ responses do not merely reflect individual differences in attention but are specific to expectancy violations. Some children are better than others at detecting prediction errors—a trait that may be linked to later cognitive abilities.

Friday, July 23, 2021

A place in the brain for the sense of ‘self’

Fascinating observations from Parvizi et al, whose findings provide a causal link between the right anterior and dorsal posteromedial cortex (PMC) and the sense of self and provide unique clues about the pathophysiology of self-dissociation in neuropsychiatric conditions. Their abstract:
The posteromedial cortex (PMC) is known to be a core node of the default mode network. Given its anatomical location and blood supply pattern, the effects of targeted disruption of this part of the brain are largely unknown. Here, we report a rare case of a patient (S19_137) with confirmed seizures originating within the PMC. Intracranial recordings confirmed the onset of seizures in the right dorsal posterior cingulate cortex, adjacent to the marginal sulcus, likely corresponding to Brodmann area 31. Upon the onset of seizures, the patient reported a reproducible sense of self-dissociation—a condition he described as a distorted awareness of the position of his body in space and feeling as if he had temporarily become an outside observer to his own thoughts, his “me” having become a separate entity that was listening to different parts of his brain speak to each other. Importantly, 50-Hz electrical stimulation of the seizure zone and a homotopical region within the contralateral PMC induced a subjectively similar state, reproducibly. We supplement our clinical findings with the definition of the patient’s network anatomy at sites of interest using cortico-cortical–evoked potentials, experimental and resting-state electrophysiological connectivity, and individual-level functional imaging. This rare case of patient S19_137 highlights the potential causal importance of the PMC for integrating self-referential information and provides clues for future mechanistic studies of self-dissociation in neuropsychiatric populations.

Wednesday, July 21, 2021

From many to (n)one: Meditation and the plasticity of the predictive mind

I had a chat with my former University of Wisconsin colleague Richard Davidson during my visit to Madison, WI last week, and he pointed me to an excellent open source review article by Laukkonen and Slagter, From many to (n)one: Meditation and the plasticity of the predictive mind. They offer an integrated predictive processing account of three main styles of meditation. I just finished reading through their lucid account and plan to carefully re-read it several times. I pass on the summary points and abstract: 

Highlights

• Predictive processing provides a novel theoretical window on meditation. 
• Deconstructive meditations progressively reduce temporally deep processing. 
• Insight experiences arise during meditation due to Bayesian model reduction 
• Meditation deconstructs self models by reducing abstract processing. 
• Non-dual awareness or pure consciousness is the ‘here and now’.
Abstract
How profoundly can humans change their own minds? In this paper we offer a unifying account of deconstructive meditation under the predictive processing view. We start from simple axioms. First, the brain makes predictions based on past experience, both phylogenetic and ontogenetic. Second, deconstructive meditation brings one closer to the here and now by disengaging anticipatory processes. We propose that practicing meditation therefore gradually reduces counterfactual temporally deep cognition, until all conceptual processing falls away, unveiling a state of pure awareness. Our account also places three main styles of meditation (focused attention, open monitoring, and non-dual) on a single continuum, where each technique relinquishes increasingly engrained habits of prediction, including the predicted self. This deconstruction can also permit certain insights by making the above processes available to introspection. Our framework is consistent with the state of empirical and (neuro)phenomenological evidence and illuminates the top-down plasticity of the predictive mind. Experimental rigor, neurophenomenology, and no-report paradigms are needed to further understanding of how meditation affects predictive processing and the self.

Monday, July 19, 2021

Psilocybin induces rapid and persistent growth of dendritic spines in frontal cortex in vivo

Interesting results from Shao et al.

 Highlights

• Psilocybin ameliorates stress-related behavioral deficit in mice 
• Psilocybin increases spine density and spine size in frontal cortical pyramidal cells 
• Psilocybin-evoked structural remodeling is persistent for at least 1 month 
• The dendritic rewiring is accompanied by elevated excitatory neurotransmission
Summary
Psilocybin is a serotonergic psychedelic with untapped therapeutic potential. There are hints that the use of psychedelics can produce neural adaptations, although the extent and timescale of the impact in a mammalian brain are unknown. In this study, we used chronic two-photon microscopy to image longitudinally the apical dendritic spines of layer 5 pyramidal neurons in the mouse medial frontal cortex. We found that a single dose of psilocybin led to ∼10% increases in spine size and density, driven by an elevated spine formation rate. The structural remodeling occurred quickly within 24 h and was persistent 1 month later. Psilocybin also ameliorated stress-related behavioral deficit and elevated excitatory neurotransmission. Overall, the results demonstrate that psilocybin-evoked synaptic rewiring in the cortex is fast and enduring, potentially providing a structural trace for long-term integration of experiences and lasting beneficial actions.
Graphical Abstract:

Friday, July 16, 2021

Albert Einstein Quotes

I am sending on some juicy Albert Einstein quotes posted by one of the members of the Madison Wisconsin book group that I still belong to...
 
“I didn't arrive at my understanding of the fundamental laws of the universe through my rational mind.”
 
“Concerning matter, we have been all wrong. What we have called matter is energy, whose vibration has been so lowered as to be perceptible to the senses. Matter is spirit reduced to point of visibility. There is no matter.”
 
"Time and space are not conditions in which we live, but modes by which we think. Physical concepts are free creations of the human mind, and are not, however it may seem, determined by the external world."
 
“Time does not exist – we invented it. Time is what the clock says. The distinction between the past, present and future is only a stubbornly persistent illusion.”
 
“I think 99 times and find nothing. I stop thinking, swim in silence, and the truth comes to me."
 
"The intellect has little to do on the road to discovery. There comes a leap in consciousness, call it intuition or what you will, the solution comes to you and you don’t know how or why.”
 
"A human being experiences himself, his thoughts and feelings as something separated from the rest, a kind of optical delusion of consciousness. This delusion is a kind of prison for us, restricting us to our personal desires and to affection for a few persons nearest to us. Our task must be to free ourselves from this prison by widening our circle of compassion to embrace all living creatures and the whole of nature in its beauty."
 
"Our separation from each other is an optical illusion."
 
“When something vibrates, the electrons of the entire universe resonate with it. Everything is connected. The greatest tragedy of human existence is the illusion of separateness.”
 
“Reality is merely an illusion, albeit a very persistent one.”
 
“We are souls dressed up in sacred biochemical garments and our bodies are the instruments through which our souls play their music.”
 
“When you examine the lives of the most influential people who have ever walked among us, you discover one thread that winds through them all. They have been aligned first with their spiritual nature and only then with their physical selves.”
 
“The true value of a human being can be found in the degree to which he has attained liberation from the self.”
 
“The ancients knew something, which we seem to have forgotten.”
 
“The more I learn of physics, the more I am drawn to metaphysics.”
 
“One thing I have learned in a long life: that all our science, measured against reality, is primitive and childlike. We still do not know one thousandth of one percent of what nature has revealed to us. It is entirely possible that behind the perception of our senses, worlds are hidden of which we are unaware.”
 
“I’m not an atheist. The problem involved is too vast for our limited minds. We are in the position of a little child entering a huge library filled with books in many languages. The child knows someone must have written those books.”
 
"The common idea that I am an atheist is based on a big mistake. Anyone who interprets my scientific theories this way, did not understand them."
 
"Everything is determined, every beginning and ending, by forces over which we have no control. It is determined for the insect, as well as for the star. Human beings, vegetables, or cosmic dust, we all dance to a mysterious tune, intoned in the distance by an invisible piper."
 
“The religion of the future will be a cosmic religion. It will transcend a personal God and avoid dogma and theology.”
 
“Energy cannot be created or destroyed, it can only be changed from one form to another.”
 
“Everything is energy and that is all there is to it. Match the frequency of the reality you want and you can not help but get that reality. It can be no other way. This is not philosophy. This is physics.”
 
"I am happy because I want nothing from anyone. I do not care about money. Decorations, titles or distinctions mean nothing to me. I do not crave praise. I claim credit for nothing. A happy man is too satisfied with the present to dwell too much on the future."

 

Thursday, July 15, 2021

Evolutionary models of financial markets.

Levin and Lo's introduction of a PNAS special issue on evolutionary models of financial markets is an interesting read. A few clips:
The brilliant evolutionary insights of Darwin and others have revolutionized our understanding of the world. Darwin was impressed by the “tangled bank” of elaborate forms that emerged from the undirected processes of evolution to produce the complexity of the biological world. Through continuous innovation coupled with the deceptively simple filter known as natural selection, the characteristics of species and their interactions change in response to changing environments. However, evolution is not limited only to the biological world. Wherever the evolutionary forces of reproduction, variation, and selection exist—as they do in financial markets—evolutionary consequences will follow. There are of course major differences as well between the nature of the evolutionary process in ecological and economic contexts, largely influenced by the relative importance of top-down control, and the degree to which predictive models and long-term planning can be invoked. These are, however, differences of degree.
There are profound similarities between financial systems and the biosphere. Both are complex adaptive systems in which individual agents act to enhance their own interests and objectives, leading to self-organization and emergent features. In viewing global financial markets as comprising a complex-adaptive biological system, researchers in this area intend to develop more effective models to understand these systems. This is not only of theoretical interest, but also has the practical aim to promote economic growth while maintaining financial stability, with the ultimate goal of allocating resources more efficiently through better financial methods.
Evolution is about short-term, relative optimality with respect to other participants in the system. In the biosphere, natural selection acts to improve reproductive success relative to the benchmark of other genomes, within and across species. Evolutionary change can thus be thought of in terms of differential fitness: that is, small differences in reproductive rates between individuals over time leading to large differences in populations. Even the very mechanisms of evolution—including those that generate new variation—are subject to constant modification. In the financial world, the evolutionary forces of mutation, recombination, reproduction, and selection often work on financial institutions and market participants through direct competition, finance “red in tooth and claw.” Financial concepts and strategies thus reproduce themselves through cultural transmission and adoption based on their success in the marketplace. These strategies undergo variation through financial innovation, analogous to mutation or genetic recombination in a biological system, but take place at the level of information and abstract thought in financial contexts. It is “survival of the richest.”
The evolutionary lens provides a natural way to introduce biological concepts into financial and economic analysis. As the evolutionary biologist Theodosius Dobzhansky said, “Nothing in biology makes sense except in the light of evolution” (5). The same may hold for the financial world. Phenomena that have been difficult to analyze within a traditional economic framework, such as growth, size, scale, self-organization, the lifecycle of products and industries, bull/bear market cycles, and the rate of variation or innovation within a system, are all subject to evolutionary forces, whether they take place in the Petri dish or on the trading floor. Biological experiments thus may be able to directly inform economic insights, and market behavior may be able to shed light on evolutionary mysteries in the biological world.