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.