Our brains remember the good stuff.

Anderson et al. show how our brains are attracted to items that have pleased us in the past, even if they are no longer relevant. People in a study were asked to look at a computer screen filled with colored objects and find the red and green ones, They received a small amount of money for each red or green object found. On the next day, the subjects were asked to find certain shapes on the screen, the color being irrelevant. Even so, when a red object appeared it captured attention, and PET brain imaging showed dopamine release in the ventral striatum, which plays a role in reward learning. Here is their technical abstract:

Highlights
•We examined the neural correlates of value-based attention using PET
•Previously reward-associated stimuli involuntary captured attention as distractors
•Such attentional capture was predicted by dopamine release in the dorsal striatum
•Our findings elucidate the neurochemical basis of value-based distraction

Summary
Reward learning gives rise to strong attentional biases. Stimuli previously associated with reward automatically capture visual attention regardless of intention. Dopamine signaling within the ventral striatum plays an important role in reward learning, representing the expected reward initiated by a cue. How dopamine and the striatum may be involved in maintaining behaviors that have been shaped by reward learning, even after reward expectancies have changed, is less well understood. Nonspecific measures of brain activity have implicated the striatum in value-based attention. However, the neurochemical mechanisms underlying the attentional priority of learned reward cues remain unexplored. Here, we investigated the contribution of dopamine to value-based attention using positron emission tomography (PET) with [11C]raclopride. We show that, in the explicit absence of reward, the magnitude of attentional capture by previously reward-associated but currently task-irrelevant distractors is correlated across individuals with changes in available D2/D3 dopamine receptors (presumably due to intrasynaptic dopamine) linked to distractor processing within the right caudate and posterior putamen. Our findings provide direct evidence linking dopamine signaling within the striatum to the involuntary orienting of attention, and specifically to the attention-grabbing quality of learned reward cues. These findings also shed light on the neurochemical basis of individual susceptibility to value-driven attentional capture, which is known to play a role in addiction. More broadly, the present study highlights the value and feasibility of using PET to relate changes in the release of a neurotransmitter to learning-dependent changes in healthy adults.

Brain games and driving safely.

I've done a number of posts on brain games (cf. here, here, and here) and their critics. When I overcome my lassitude and occasionally return to dink with one of the BrainHQ games, I am struck by at least temporary improvements in the cognitive activity being refined, particularly with the vision exercises dealing with useful field of view, contrast sensitivity, etc. The exercise called Double Decision seems to me especially effective. I notice an effect on my driving after playing it. I thought I would pass on this BrainHQ web page on research on BrainHQ exercises. Their claim is that the studies have shown that after training, drivers on average:

-Make 38% fewer dangerous driving maneuvers
-Can stop 22 feet sooner when driving 55 miles per hour
-Feel more confident driving in difficult conditions (such as at night, in bad weather, or in new places)
-Cut their at-fault crash risk by 48%
-Keep their license later in life

Wearing a bike helmet increases risk taking.

From Gamble and Walker:

Humans adapt their risk-taking behavior on the basis of perceptions of safety; this risk-compensation phenomenon is typified by people taking increased risks when using protective equipment. Existing studies have looked at people who know they are using safety equipment and have specifically focused on changes in behaviors for which that equipment might reduce risk. Here, we demonstrated that risk taking increases in people who are not explicitly aware they are wearing protective equipment; furthermore, this happens for behaviors that could not be made safer by that equipment. In a controlled study in which a helmet, compared with a baseball cap, was used as the head mount for an eye tracker, participants scored significantly higher on laboratory measures of both risk taking and sensation seeking. This happened despite there being no risk for the helmet to ameliorate and despite it being introduced purely as an eye tracker. The results suggest that unconscious activation of safety-related concepts primes globally increased risk propensity.

Brahms Waltzes Op. 39, Nos. 1,13,14

Recorded on my Steinway B, now in my Fort Lauderdale condo. I did this piece in recitals in Madison WI and Fort Lauderdale in the past 6 months, and now have made a good quality video recording for my youtube channel. I plan to do this with several of the pieces played at the recitals.


The first of the waltzes has a very robust opening that always brings back memories of my listening to a Saturday morning radio program produced by KTBC in Austin Texas, that invited students taking music lessons to perform a piece, which I dutifully did when I was 12. The program’s opening music was the first of these Brahms waltzes, and I couldn’t imagine ever being able to play something that sounded so difficult.

Stephen Wolfram on A.I. and the future of civilization

Some clips from a Wolfram discussion (well worth reading) that notes the limits of doing things with machines...

The machine is able to execute things, but something or someone has to define what its goals should be and what it's trying to execute.

What makes us different from all these things? What makes us different is the particulars of our history, which gives us our notions of purpose and goals. That's a long way of saying when we have the box on the desk that thinks as well as any brain does, the thing it doesn't have, intrinsically, is the goals and purposes that we have. Those are defined by our particulars—our particular biology, our particular psychology, our particular cultural history.

The thing we have to think about as we think about the future of these things is the goals. That's what humans contribute, that's what our civilization contributes—execution of those goals; that's what we can increasingly automate. We've been automating it for thousands of years. We will succeed in having very good automation of those goals. I've spent some significant part of my life building technology to essentially go from a human concept of a goal to something that gets done in the world.

Repeated social defeat causes neuroinflammation and memory impairment.

I pass on the significance statement from McKim et al., the link gives the more technical abstract.

Repeated exposure to stress alters the homeostatic environment of the brain, giving rise to various cognitive and mood disorders that impair everyday functioning and overall quality of life. The brain, previously thought of as an immune-privileged organ, is now known to communicate extensively with the peripheral immune system. This brain–body communication plays a significant role in various stress-induced inflammatory conditions, also characterized by psychological impairments. Findings from this study implicate neuroimmune activation rather than impaired neurogenesis in stress-induced cognitive deficits. This idea opens up possibilities for novel immune interventions in the treatment of cognitive and mood disturbances, while also adding to the complexity surrounding the functional implications of adult neurogenesis.

Punishment of others: decreased by status in the West, increased in the East

An interesting commentary from Kuwabara et al.:

In the experiments reported here, we integrated work on hierarchy, culture, and the enforcement of group cooperation by examining patterns of punishment. Studies in Western contexts have shown that having high status can temper acts of dominance, suggesting that high status may decrease punishment by the powerful. We predicted that high status would have the opposite effect in Asian cultures because vertical collectivism permits the use of dominance to reinforce the existing hierarchical order. Across two experiments, having high status decreased punishment by American participants but increased punishment by Chinese and Indian participants. Moreover, within each culture, the effect of status on punishment was mediated by feelings of being respected. A final experiment found differential effects of status on punishment imposed by Asian Americans depending on whether their Asian or American identity was activated. Analyzing enforcement through the lens of hierarchy and culture adds insight into the vexing puzzle of when and why people engage in punishment.

More on clever crows - they learn shell games.

Chopin Trois Eccossaises

Recorded on my Steinway B, now in my Fort Lauderdale condo. I did this piece in recitals in Madison WI and Fort Lauderdale in the past 6 months, and now have made a good quality video recording for my youtube channel. I plan to do this with several of the pieces played at the recitals.

New nerve cells in the brain generated best by sustained aerobic exercise

Nokia et al. show, in rats, that aerobic exercise is much more effective than high-intensity interval training or resistance training in enhancing generation of new nerve cells in the hippocampus of the brain.

Key points

Aerobic exercise such as running enhances adult hippocampal neurogenesis (AHN) in rodents. 

Little is known about the effects of high-intensity interval training (HIT) or of purely anaerobic resistance training on AHN. 

Here, compared to a sedentary lifestyle, we report a very modest effect of HIT and no effect of resistance training on AHN in adult male rats. 

We find most AHN in rats that were selectively bred for an innately high response to aerobic exercise that also run voluntarily and - increase maximum running capacity. 

Our results confirm that sustained aerobic exercise is key in improving AHN.

Abstract

Aerobic exercise, such as running, has positive effects on brain structure and function, for example, adult hippocampal neurogenesis (AHN) and learning. Whether high-intensity interval training (HIT), referring to alternating short bouts of very intense anaerobic exercise with recovery periods, or anaerobic resistance training (RT) has similar effects on AHN is unclear. In addition, individual genetic variation in the overall response to physical exercise likely plays a part in the effects of exercise on AHN but is less studied. Recently, we developed polygenic rat models that gain differentially for running capacity in response to aerobic treadmill training. Here we subjected these Low Response Trainer (LRT) and High Response Trainer (HRT) adult male rats to various forms of physical exercise for 6 to 8 weeks and examined its effects on AHN. Compared to sedentary animals, the highest number of doublecortin-positive hippocampal cells was observed in HRT rats that ran voluntarily on a running wheel while HIT on the treadmill had a smaller, statistically non-significant effect on AHN. AHN was elevated in both LRT and HRT rats that endurance trained on a treadmill compared to those that performed RT by climbing a vertical ladder with weights, despite their significant gain in strength. Furthermore, RT had no effect on proliferation (Ki67), maturation (doublecortin) or survival (BrdU) of new adult-born hippocampal neurons in adult male Sprague-Dawley rats. Our results suggest physical exercise promotes AHN most if it is aerobic and sustained, and especially when accompanied by a heightened genetic predisposition for response to physical exercise.

This is too good not to pass on.....

If all the world's a stage, do we have a true self?

My reading of Irving Goffman's classic "The Presentation of the Self in Everyday Life" in the early 1970's was the beginning of my going beyond my laboratory research on the molecules of vision to start a parallel line of study and reading on how our minds work (see dericbownds.net). I recently came across this engaging very brief video on Goffman's ideas, narrated by Stephen Fry, and thought I would pass it on. (This is one of the items from the BBC's excellent "A History of Ideas" series.)

"Well-being" as a practiced skill

I thought I would pass on from the mindful.org website yet another piece featuring my Wisconsin colleague Richie Davidson, noting his presentation on "Four Constituents of Well-Being," namely:

Resilience - rapid recovery from shit happening
Outlook -savoring positive, seeing good in people
Attention - a wandering mind is an unhappy mind
Generosity - kindness to oneself and others

The article has numerous links to research on good stuff which offers a temporary relief from the dystopian input of our entertainment and news overlords.

Getting rid of old cells extends lifespan of mice and ameliorates age-related diseases.

Baker et al. show that getting rid of cells that have entered an irreversible senescent state expands the lifespan of mice and ameliorates some age-related disease processes. Clips from the Gil and Withers summary of the work:

More than 50 years ago, it was suggested that ageing is linked to a state of arrested cell growth known as senescence, but this link has remained unproven, and the molecular basis for organismal ageing has been elusive...Senescence is a cellular state in which cells permanently stop dividing. It is mediated by two signalling pathways — the p53 pathway and the p16Ink4a–Rb pathway. Senescent cells secrete a complex cocktail of factors called the senescence-associated secretory phenotype (SASP), which includes matrix metalloproteinases (enzymes that break down the extracellular matrix) and pro-inflammatory signalling molecules. Such cells have been shown to accumulate during ageing, and their presence has been associated with a broad range of diseases, including diabetes, kidney disease and many cancers.

Baker et al. demonstrate that the removal of senescent cells does indeed delay ageing and increase healthy lifespan (healthspan)...using a genetically engineered mouse model that they had developed previously4, called INK–ATTAC. These mice produce a caspase enzyme specifically in cells that express the p16Ink4a gene. The caspase can be activated by the injection of a drug; the activated caspase then triggers cell death, eliminating senescent cells in which it is expressed...[They] found that the elimination of p16Ink4a-expressing cells increased lifespan, regardless of the sex or strain of mouse examined, and ameliorated a range of age-dependent, disease-related abnormalities, including kidney dysfunction and abnormalities in heart and fat tissue.

A brain circuit for loneliness.

Tye and colleagues find a neural circuit at the base of mouse brains that drives loneliness-like behaviors and drives the animals to seek company. From a review:

...connections between neurons in the circuit were stronger in mice that were separated from their cage mates than in those that were grouped together. Those neurons then fired more frequently when isolated mice were put in a cage with an unfamiliar mouse, compared with animals that had not been isolated. When the scientists inhibited the neurons with light, the isolated mice showed less interest in the stranger. Activating those neurons caused the animals to actively seek other mice.

Here is the abstract for the work:

Highlights

•Dorsal raphe nucleus (DRN) dopamine neurons are sensitive to acute social isolation 

•DRN dopamine neurons release dopamine and glutamate in downstream structures 

•Optical activation induces, whereas inhibition suppresses, a “loneliness-like” state 

•Social rank predicts the behavioral effect induced by optical manipulations

Summary

The motivation to seek social contact may arise from either positive or negative emotional states, as social interaction can be rewarding and social isolation can be aversive. While ventral tegmental area (VTA) dopamine (DA) neurons may mediate social reward, a cellular substrate for the negative affective state of loneliness has remained elusive. Here, we identify a functional role for DA neurons in the dorsal raphe nucleus (DRN), in which we observe synaptic changes following acute social isolation. DRN DA neurons show increased activity upon social contact following isolation, revealed by in vivo calcium imaging. Optogenetic activation of DRN DA neurons increases social preference but causes place avoidance. Furthermore, these neurons are necessary for promoting rebound sociability following an acute period of isolation. Finally, the degree to which these neurons modulate behavior is predicted by social rank, together supporting a role for DRN dopamine neurons in mediating a loneliness-like state.

Winning a competition predicts dishonest behavior.

Interesting observations from Schurr and Ritov:

Significance

Competition is prevalent. People often resort to unethical means to win (e.g., the recent Volkswagen scandal). Not surprisingly, competition is central to the study of economics, psychology, sociology, political science, and more. Although we know much about contestants’ behavior before and during competitions, we know little about contestants’ behavior after the competition has ended. Connecting postcompetition behaviors with preceding competition experience, we find that after a competition is over winners behave more dishonestly than losers in an unrelated subsequent task. Furthermore, the subsequent unethical behavior effect seems to depend on winning, rather than on mere success. Providing insight into the issue is important in gaining understanding of how unethical behavior may cascade from exposure to competitive settings.

Abstract

Winning a competition engenders subsequent unrelated unethical behavior. Five studies reveal that after a competition has taken place winners behave more dishonestly than competition losers. Studies 1 and 2 demonstrate that winning a competition increases the likelihood of winners to steal money from their counterparts in a subsequent unrelated task. Studies 3a and 3b demonstrate that the effect holds only when winning means performing better than others (i.e., determined in reference to others) but not when success is determined by chance or in reference to a personal goal. Finally, study 4 demonstrates that a possible mechanism underlying the effect is an enhanced sense of entitlement among competition winners.

Abnormal cortical folding correlates with trait anxiety.

From Miskovich et al. at the Univ. of Wisconsin, Milwaukee :

Dispositional anxiety is a stable personality trait that is a key risk factor for internalizing disorders, and understanding the neural correlates of trait anxiety may help us better understand the development of these disorders. Abnormal cortical folding is thought to reflect differences in cortical connectivity occurring during brain development. Therefore, assessing gyrification may advance understanding of cortical development and organization associated with trait anxiety. Previous literature has revealed structural abnormalities in trait anxiety and related disorders, but no study to our knowledge has examined gyrification in trait anxiety. We utilized a relatively novel measure, the local gyrification index (LGI), to explore differences in gyrification as a function of trait anxiety. We obtained structural MRI scans using a 3T magnetic resonance scanner on 113 young adults. Results indicated a negative correlation between trait anxiety and LGI in the left superior parietal cortex, specifically the precuneus, reflecting less cortical complexity among those high on trait anxiety. Our findings suggest that aberrations in cortical gyrification in a key region of the default mode network is a correlate of trait anxiety and may reflect disrupted local parietal connectivity.

Inflated and pial surface maps of the left hemisphere demonstrating decreased gyrification in the precuneus as a function of trait anxiety.There was no relationship between anxiety and gyrification in the right hemisphere. Images on the left depict the medial view of the left hemisphere. Images on the right are a view from the top of the right hemisphere and are tilted 30 degrees to provide a better angle for viewing the cluster extent.

Moralistic gods enhance sociality.

Purzycki et al. combine laboratory experiments, cross-cultural fieldwork, and analysis of the historical record to propose that belief in judgmental deities was key to the cooperation needed to build and sustain large, complex societies.

Since the origins of agriculture, the scale of human cooperation and societal complexity has dramatically expanded. This fact challenges standard evolutionary explanations of prosociality because well-studied mechanisms of cooperation based on genetic relatedness, reciprocity and partner choice falter as people increasingly engage in fleeting transactions with genetically unrelated strangers in large anonymous groups. To explain this rapid expansion of prosociality, researchers have proposed several mechanisms. Here we focus on one key hypothesis: cognitive representations of gods as increasingly knowledgeable and punitive, and who sanction violators of interpersonal social norms, foster and sustain the expansion of cooperation, trust and fairness towards co-religionist strangers. We tested this hypothesis using extensive ethnographic interviews and two behavioural games designed to measure impartial rule-following among people (n = 591, observations = 35,400) from eight diverse communities from around the world: (1) inland Tanna, Vanuatu; (2) coastal Tanna, Vanuatu; (3) Yasawa, Fiji; (4) Lovu, Fiji; (5) Pesqueiro, Brazil; (6) Pointe aux Piments, Mauritius; (7) the Tyva Republic (Siberia), Russia; and (8) Hadzaland, Tanzania. Participants reported adherence to a wide array of world religious traditions including Christianity, Hinduism and Buddhism, as well as notably diverse local traditions, including animism and ancestor worship. Holding a range of relevant variables constant, the higher participants rated their moralistic gods as punitive and knowledgeable about human thoughts and actions, the more coins they allocated to geographically distant co-religionist strangers relative to both themselves and local co-religionists. Our results support the hypothesis that beliefs in moralistic, punitive and knowing gods increase impartial behaviour towards distant co-religionists, and therefore can contribute to the expansion of prosociality.

Creative cognition and brain network dynamics.

Beaty et al. do a review that notes trends in recent neuroimaging studies suggesting that creative cognition involves increased cooperation of the default and executive control networks of our brain (Motivated readers can obtain the article from me.)

Several recent neuroimaging studies have found that creative cognition involves increased cooperation of the default and executive control networks, brain systems linked to self-generated thought and cognitive control.

Default–control network interactions occur during cognitive tasks that involve the generation and evaluation of creative ideas. This pattern of brain network connectivity has been reported across domain-general creative problem solving (e.g., divergent thinking) and domain-specific artistic performance (e.g., poetry composition, musical improvisation, and visual art production).

Default network activity during creative cognition appears to reflect the spontaneous generation of candidate ideas, or potentially useful information derived from long-term memory.

The control network may couple with the default network during idea generation or evaluation to constrain cognition to meet specific task goals.

Dorsolateral Prefrontal Cortex Connectivity During Musical Improvisation. The right dorsolateral prefrontal cortex (DLPFC; green) shows differential connectivity as a function of task goals during musical improvisation in professional pianists. (A) Functional connectivity associated with the goal of using specific sets of piano keys; brain maps show increased coupling between the right DLPFC and motor regions (yellow, e.g., dorsal pre-motor area and the pre-supplementary motor area). (B) Functional connectivity associated with the goal of expressing specific emotions; brain maps show increased coupling between the right DLPFC and default network regions [blue, e.g., medial prefrontal cortex (MPFC), posterior cingulate cortex (PCC), and bilateral inferior parietal lobule (IPL)].

A mindfulness meditation intervention enhances connectivity of brain executive and default modes and lowers inflammation markers.

Creswell et al. recruited 35 stressed-out adult job-seekers, getting half to participate in an intensive three-day mindfulness meditation retreat while the other half completed a three day relaxation retreat program without the mindfulness component. Brain scans and blood samples were obtained before and four months after the program. The result was that mindfulness meditation correlated with reduced blood levels of interleukin-6, a marker of stress and inflammation, and increased functional connectivity between the participants’ resting default mode network and areas in the dorsolateral prefrontal cortex important to attention and executive control. Neither of these changes were seen in participants who received only the relaxation training. The suggestion is that the brain changes cause the decrease in inflammatory markers. Here are some clips of context from their introduction:

Mindfulness meditation training programs, which train receptive attention and awareness to one’s present moment experience, have been shown to improve a broad range of stress-related psychiatric and physical health outcomes in initial randomized controlled trials...recent well-controlled studies indicate that mindfulness meditation training may reduce markers of inflammation (C Reactive Protein, Interleukin-6 (IL-6), neurogenic inflammation) in stressed individuals.

One possibility is that mindfulness meditation training alters resting state functional connectivity (rsFC) of brain networks implicated in mind wandering (the Default Mode Network, DMN) and executive control (the Executive Control Network, EC), which in turn improves emotion regulation, stress resilience, and stress-related health outcomes in at-risk patient populations.... a cross-sectional study (N=25) showed that advanced mindfulness meditation practitioners had increased functional connectivity of a key hub in the default mode network (DMN) (i.e., posterior cingulate cortex) with regions considered to be important in top down executive control (EC) (dorsolateral prefrontal cortex, dorsal ACC), both at rest and during a guided mindfulness meditation practice. This coupling of one’s DMN at rest with regions of the EC network may be important for emotion regulation and stress resilience effects, as greater activation and functional connectivity of EC regions, such as the dlPFC, is associated with reduced pain, negative affect, and stress.

Here we provide the first experimental test of whether an intensive 3-day mindfulness meditation training intervention (relative to a relaxation training intervention) alters DMN connectivity and circulating IL-6 in a high stress unemployed job-seeking community sample. IL-6 is an established clinical health biomarker that is elevated in high stress populations and is associated with elevated cardiovascular disease and mortality risk... unemployment is a well-known chronic stressor that can foster a loss of control, helplessness, and financial setbacks, and unemployment is associated with elevated inflammation. Building on initial cross-sectional evidence (17), we hypothesized that mindfulness meditation training would increase rsFC between the DMN and regions implicated in attention and executive control (dlPFC and dACC). Moreover, we tested whether mindfulness meditation training (relative to relaxation training) decreased circulating IL-6 at 4-month follow up, and whether pre-post intervention increases in DMN-dlPFC rsFC mediated IL-6 improvements at 4-month follow-up.