Welcome to the Nexus of Ethics, Psychology, Morality, Philosophy and Health Care

Welcome to the nexus of ethics, psychology, morality, technology, health care, and philosophy
Showing posts with label fMRI. Show all posts
Showing posts with label fMRI. Show all posts

Monday, April 10, 2023

Revealing the neurobiology underlying interpersonal neural synchronization with multimodal data fusion

Lotter, L. D., Kohl, S. H.,  et al. (2023).
Neuroscience & Biobehavioral Reviews,
146, 105042. 

Abstract

Humans synchronize with one another to foster successful interactions. Here, we use a multimodal data fusion approach with the aim of elucidating the neurobiological mechanisms by which interpersonal neural synchronization (INS) occurs. Our meta-analysis of 22 functional magnetic resonance imaging and 69 near-infrared spectroscopy hyperscanning experiments (740 and 3721 subjects) revealed robust brain regional correlates of INS in the right temporoparietal junction and left ventral prefrontal cortex. Integrating this meta-analytic information with public databases, biobehavioral and brain-functional association analyses suggested that INS involves sensory-integrative hubs with functional connections to mentalizing and attention networks. On the molecular and genetic levels, we found INS to be associated with GABAergic neurotransmission and layer IV/V neuronal circuits, protracted developmental gene expression patterns, and disorders of neurodevelopment. Although limited by the indirect nature of phenotypic-molecular association analyses, our findings generate new testable hypotheses on the neurobiological basis of INS.

Highlights

• When we interact, both our behavior and our neural activity synchronize.

• Neuroimaging meta-analysis and multimodal data fusion may reveal neural mechanisms.

• Robust involvement of right temporoparietal and left prefrontal brain regions.

• Associations to attention and mentalizing, GABA and layer IV/V neurotransmission.

• Brain-wide associated genes are enriched in neurodevelopmental disorders.

Discussion

In recent years, synchronization of brain activities between interacting partners has been acknowledged as a central mechanism by which we foster successful social relationships as well as a potential factor involved in the pathogenesis of diverse neuropsychiatric disorders. Based on the results generated by our multimodal data fusion approach (see Fig. 5), we hypothesized that human INS is tightly linked to social attentional processing, subserved by the rTPJ as a sensory integration hub at the brain system level, and potentially facilitated by GABA-mediated E/I balance at the neurophysiological level.


Note: The interpersonal neural synchronization is a fascinating piece of research.  How to improve the synchronization may help with effective psychotherapy.

Saturday, October 29, 2022

Sleep loss leads to the withdrawal of human helping across individuals, groups, and large-scale societies

Ben Simon E, Vallat R, Rossi A, Walker MP (2022) 
PLoS Biol 20(8): e3001733.
https://doi.org/10.1371/journal.pbio.3001733

Abstract

Humans help each other. This fundamental feature of homo sapiens has been one of the most powerful forces sculpting the advent of modern civilizations. But what determines whether humans choose to help one another? Across 3 replicating studies, here, we demonstrate that sleep loss represents one previously unrecognized factor dictating whether humans choose to help each other, observed at 3 different scales (within individuals, across individuals, and across societies). First, at an individual level, 1 night of sleep loss triggers the withdrawal of help from one individual to another. Moreover, fMRI findings revealed that the withdrawal of human helping is associated with deactivation of key nodes within the social cognition brain network that facilitates prosociality. Second, at a group level, ecological night-to-night reductions in sleep across several nights predict corresponding next-day reductions in the choice to help others during day-to-day interactions. Third, at a large-scale national level, we demonstrate that 1 h of lost sleep opportunity, inflicted by the transition to Daylight Saving Time, reduces real-world altruistic helping through the act of donation giving, established through the analysis of over 3 million charitable donations. Therefore, inadequate sleep represents a significant influential force determining whether humans choose to help one another, observable across micro- and macroscopic levels of civilized interaction. The implications of this effect may be non-trivial when considering the essentiality of human helping in the maintenance of cooperative, civil society, combined with the reported decline in sufficient sleep in many first-world nations.

From the Discussion section

Taken together, findings across all 3 studies establish insufficient sleep (both quantity and quality) as a degrading force influencing whether or not humans wish to help each other, and do indeed, choose to help each other (through real-world altruistic acts), observable at 3 different societal scales: within individuals, across individuals, and at a nationwide level.

Study 1 established not only the causal impact of sleep loss on the basic desire to help another human being, but further characterised the central underlying brain mechanism associated with this altered phenotype of diminished helping. Specifically, sleep loss significantly and selectively reduced activity throughout key nodes of the social cognition brain network (see Fig 1B) normally associated with prosociality, including perspective taking of others’ mental state, their emotions, and their personal needs. Therefore, impairment of this neural system caused by a lack of sleep represents one novel pathway explaining the associated withdrawal of helping desire and the decisional act to offer such help.

Wednesday, July 14, 2021

Popularity is linked to neural coordination: Neural evidence for an Anna Karenina principle in social networks

Baek, E. C.,  et al. (2021)
https://doi.org/10.31234/osf.io/6fj2p

Abstract

People differ in how they attend to, interpret, and respond to their surroundings. Convergent processing of the world may be one factor that contributes to social connections between individuals. We used neuroimaging and network analysis to investigate whether the most central individuals in their communities (as measured by in-degree centrality, a notion of popularity) process the world in a particularly normative way. More central individuals had exceptionally similar neural responses to their peers and especially to each other in brain regions associated with high-level interpretations and social cognition (e.g., in the default-mode network), whereas less-central individuals exhibited more idiosyncratic responses. Self-reported enjoyment of and interest in stimuli followed a similar pattern, but accounting for these data did not change our main results. These findings suggest an “Anna Karenina principle” in social networks: Highly-central individuals process the world in exceptionally similar ways, whereas less-central individuals process the world in idiosyncratic ways.

Discussion

What factors distinguish highly-central individuals in social networks? Our results are consistent with the notion that popular individuals (who are central in their social networks) process the world around them in normative ways, whereas unpopular individuals process the world around them idiosyncratically. Popular individuals exhibited greater mean neural similarity with their peers than unpopular individuals in several regions of the brain, including ones in which similar neural responding has been associated with shared higher-level interpretations of events and social cognition (e.g., regions of the default mode network) while viewing dynamic, naturalistic stimuli. Our results indicate that the relationship between popularity and neural similarity follows anAnna Karenina principle. Specifically, we observed that popular individuals were very similar to each other in their neural responses, whereas unpopular individuals were dissimilar both to each other and to their peers’ normative way of processing the world.  Our findings suggest that highly-central people process and respond to the world around them in a manner that allows them to relate to and connect with many of their peers and that less-central people exhibit idiosyncrasies that may result in greater difficulty in relating to others.

Wednesday, June 24, 2020

Shifting prosocial intuitions: neurocognitive evidence for a value-based account of group-based cooperation

Leor M Hackel, Julian A Wills, Jay J Van Bavel
Social Cognitive and Affective Neuroscience
nsaa055, https://doi.org/10.1093/scan/nsaa055

Abstract

Cooperation is necessary for solving numerous social issues, including climate change, effective governance and economic stability. Value-based decision models contend that prosocial tendencies and social context shape people’s preferences for cooperative or selfish behavior. Using functional neuroimaging and computational modeling, we tested these predictions by comparing activity in brain regions previously linked to valuation and executive function during decision-making—the ventromedial prefrontal cortex (vmPFC) and dorsolateral prefrontal cortex (dlPFC), respectively. Participants played Public Goods Games with students from fictitious universities, where social norms were selfish or cooperative. Prosocial participants showed greater vmPFC activity when cooperating and dlPFC-vmPFC connectivity when acting selfishly, whereas selfish participants displayed the opposite pattern. Norm-sensitive participants showed greater dlPFC-vmPFC connectivity when defying group norms. Modeling expectations of cooperation was associated with activity near the right temporoparietal junction. Consistent with value-based models, this suggests that prosocial tendencies and contextual norms flexibly determine whether people prefer cooperation or defection.

From the Discussion section

The current research further indicates that norms shape cooperation. Participants who were most attentive to norms aligned their behavior with norms and showed greater right dlPFC-vmPFC connectivity when deviating from norms, whereas the least attentive participants showed the reverse pattern. Curiously, we found no clear evidence that decisions to conform were more valued than decisions to deviate. This conflicts with work suggesting social norms boost the value of norm compliance (Nook and Zaki, 2015). Instead, our findings suggest that norm compliance can also stem from increased functional connectivity between vmPFC and dlPFC.

The research is here.

Wednesday, June 26, 2019

The computational and neural substrates of moral strategies in social decision-making

Jeroen M. van Baar, Luke J. Chang & Alan G. Sanfey
Nature Communications, Volume 10, Article number: 1483 (2019)

Abstract

Individuals employ different moral principles to guide their social decision-making, thus expressing a specific ‘moral strategy’. Which computations characterize different moral strategies, and how might they be instantiated in the brain? Here, we tackle these questions in the context of decisions about reciprocity using a modified Trust Game. We show that different participants spontaneously and consistently employ different moral strategies. By mapping an integrative computational model of reciprocity decisions onto brain activity using inter-subject representational similarity analysis of fMRI data, we find markedly different neural substrates for the strategies of ‘guilt aversion’ and ‘inequity aversion’, even under conditions where the two strategies produce the same choices. We also identify a new strategy, ‘moral opportunism’, in which participants adaptively switch between guilt and inequity aversion, with a corresponding switch observed in their neural activation patterns. These findings provide a valuable view into understanding how different individuals may utilize different moral principles.

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From the Discussion

We also report a new strategy observed in participants, moral opportunism. This group did not consistently apply one moral rule to their decisions, but rather appeared to make a motivational trade-off depending on the particular trial structure. This opportunistic decision strategy entailed switching between the behavioral patterns of guilt aversion and inequity aversion, and allowed participants to maximize their financial payoff while still always following a moral rule. Although it could have been the case that these opportunists merely resembled GA and IA in terms of decision outcome, and not in the underlying psychological process, a confirmatory analysis showed that the moral opportunists did in fact switch between the neural representations of guilt and inequity aversion, and thus flexibly employed the respective psychological processes underlying these two, quite different, social preferences. This further supports our interpretation that the activity patterns directly reflect guilt aversion and inequity aversion computations, and not a theoretically peripheral “third factor” shared between GA or IA participants. Additionally, we found activity patterns specifically linked to moral opportunism in the superior parietal cortex and dACC, which are strongly associated with cognitive control and working memory.

The research is here.

Tuesday, January 2, 2018

The Neuroscience of Changing Your Mind

 Bret Stetka
Scientific American
Originally published on December 7, 2017

Here are two excerpts:

Scientists have long accepted that our ability to abruptly stop or modify a planned behavior is controlled via a single region within the brain’s prefrontal cortex, an area involved in planning and other higher mental functions. By studying other parts of the brain in both humans and monkeys, however, a team from Johns Hopkins University has now concluded that last-minute decision-making is a lot more complicated than previously known, involving complex neural coordination among multiple brain areas. The revelations may help scientists unravel certain aspects of addictive behaviors and understand why accidents like falls grow increasingly common as we age, according to the Johns Hopkins team.

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Tracking these eye movements and neural action let the researchers resolve the very confusing question of what brain areas are involved in these split-second decisions, says Vanderbilt University neuroscientist Jeffrey Schall, who was not involved in the research. “By combining human functional brain imaging with nonhuman primate neurophysiology, [the investigators] weave together threads of research that have too long been separate strands,” he says. “If we can understand how the brain stops or prevents an action, we may gain ability to enhance that stopping process to afford individuals more control over their choices.”

The article is here.

Monday, July 21, 2014

Neuroimaging study shows why antisocial youths are less able to take the perspective of others

By Max Planck Gesellshft
PsyPost.Org
Originally published on March 11, 2014

Adolescents with antisocial personality disorder inflict serious physical and psychological harm on both themselves and others. However, little is yet known about the underlying neural processes. Researchers at the University of Leiden and the Max Planck Institute for Human Development have pinpointed a possible explanation: Their brain regions responsible for social information processing and impulse control are less developed.

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Adolescents with antisocial personality disorder thus seem to have difficulties in taking into account all the relevant information in social interactions, such as other people’s intentions. The researchers hypothesize that this in turn leads to more antisocial behavior.

The entire article is here.

Tuesday, July 1, 2014

When good people do bad things

Being in a group makes some people lose touch with their personal moral beliefs, researchers find

By Anne Trafton
MIT News
Originally posted June 12, 2014

When people get together in groups, unusual things can happen — both good and bad. Groups create important social institutions that an individual could not achieve alone, but there can be a darker side to such alliances: Belonging to a group makes people more likely to harm others outside the group.

“Although humans exhibit strong preferences for equity and moral prohibitions against harm in many contexts, people’s priorities change when there is an ‘us’ and a ‘them,’” says Rebecca Saxe, an associate professor of cognitive neuroscience at MIT. “A group of people will often engage in actions that are contrary to the private moral standards of each individual in that group, sweeping otherwise decent individuals into ‘mobs’ that commit looting, vandalism, even physical brutality.”

Several factors play into this transformation. When people are in a group, they feel more anonymous, and less likely to be caught doing something wrong. They may also feel a diminished sense of personal responsibility for collective actions.

The entire article is here.

Wednesday, June 18, 2014

What Are the Implications of the Free Will Debate for Individuals and Society?

By Alfred Mele
Big Questions Online
Originally posted May 6, 2014

Does free will exist? Current interest in that question is fueled by news reports suggesting that neuroscientists have proved it doesn’t. In the last few years, I’ve been on a mission to explain why scientific discoveries haven’t closed the door on free will. To readers interested in a rigorous explanation, I recommend my 2009 book, Effective Intentions. For a quicker read, you might wait for my Free: Why Science Hasn’t Disproved Free Will, to be published this fall.

One major plank in a well-known neuroscientific argument for the nonexistence of free will is the claim that participants in various experiments make their decisions unconsciously. In some studies, this claim is based partly on EEG readings (electrical readings taken from the scalp). In others, fMRI data (about changes in blood oxygen levels in the brain) are used instead. In yet others, with people whose skulls are open for medical purposes, readings are taken directly from the brain. The other part of the evidence comes from participants’ reports on when they first became aware of their decisions. If the reports are accurate (which is disputed), the typical sequence of events is as follows: first, there is the brain activity the scientists focus on, then the participants become aware of decisions (or intentions or urges) to act, and then they act, flexing a wrist or pushing a button, for example.

The entire article is here.

Tuesday, May 20, 2014

Dealing with all the behavioral conditions of unknown etiology

By Steven Reidbord
KevinMD.org
Originally published May 1, 2014

Here are some excerpts:

A few years ago I wrote that uncertainty is inevitable in psychiatry.  We literally don’t know the pathogenesis of any psychiatric disorder.  Historically, when the etiology of abnormal behavior became known, the disease was no longer considered psychiatric.  Thus, neurosyphilis and myxedema went to internal medicine; seizures, multiple sclerosis, Parkinson’s, and many other formerly psychiatric conditions went to neurology; brain tumors and hemorrhages went to neurosurgery; and so forth.

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Patients are told they suffer a “chemical imbalance” in the brain, when none has ever been shown.  Rapid advances in brain imaging and genetics have yielded an avalanche of findings that may well bring us closer to understanding the causes of mental disorders.  But they haven’t done so yet — a sad fact obscured by popular and professional rhetoric.  In particular, functional brain imaging (e.g., fMRI) fascinates brain scientists and the public alike.  We can now see, in dramatic three-dimensional colorful computer graphics, how different regions of the living brain “light up,” that is, vary in metabolic activity.  Population studies reveal systematic differences in patients with specific psychiatric disorders as compared to normals.  Don’t such images prove that psychiatric disorders are neurobiological brain diseases?

Note quite.

The entire article is here.

Thanks to Ed Zuckerman for this information.

Tuesday, March 25, 2014

The social brain and its superpowers: Matthew Lieberman

Published on Oct 7, 2013
TEDx video

Neuroscientist Matthew Lieberman explains that through his studies he's learned that our kryptonite is ignoring the importance of our social superpowers and by building on our social intuition, we can make ourselves smarter, happier, and more productive. In this TEDx Talk, Lieberman explores groundbreaking research in social neuroscience that reveals that our need to connect with other people is even more fundamental than our need for food or shelter and that the social pain and pleasure we experience has just as much impact as physical pain and pleasure.


Monday, January 13, 2014

How the brain heals emotional wounds: the functional neuroanatomy of forgiveness

Ricciardi E, Rota G, Sani L, Gentili C, Gaglianese A, Guazzelli M and Pietrini P (2013)
How the brain heals emotional wounds: the functional neuroanatomy of forgiveness.
Front. Hum. Neurosci. 7:839. doi: 10.3389/fnhum.2013.00839

In life, everyone goes through hurtful events caused by significant others: a deceiving friend, a betraying partner, or an unjustly blaming parent. In response to painful emotions, individuals may react with anger, hostility, and the desire for revenge. As an alternative, they may decide to forgive the wrongdoer and relinquish resentment. In the present study, we examined the brain correlates of forgiveness using functional Magnetic Resonance Imaging (fMRI). Healthy participants were induced to imagine social scenarios that described emotionally hurtful events followed by the indication to either forgive the imagined offenders, or harbor a grudge toward them. Subjects rated their imaginative skills, levels of anger, frustration, and/or relief when imagining negative events as well as following forgiveness. Forgiveness was associated with positive emotional states as compared to unforgiveness. Granting forgiveness was associated with activations in a brain network involved in theory of mind, empathy, and the regulation of affect through cognition, which comprised the precuneus, right inferior parietal regions, and the dorsolateral prefrontal cortex. Our results uncovered the neuronal basis of reappraisal-driven forgiveness, and extend extant data on emotional regulation to the resolution of anger and resentment following negative interpersonal events.

The entire article is here.