Neuroimaging studies exploring the neural basis of social isolation

Abstract According to the social brain hypothesis, the human brain includes a network designed for the processing of social information. This network includes several brain regions that elaborate social cues, interactions and contexts, i.e. prefrontal paracingulate and parietal cortices, amygdala, temporal lobes and the posterior superior temporal sulcus. While current literature suggests the importance of this network from both a psychological and evolutionary perspective, little is known about its neurobiological bases. Specifically, only a paucity of studies explored the neural underpinnings of constructs that are ascribed to the social brain network functioning, i.e. objective social isolation and perceived loneliness. As such, this review aimed to overview neuroimaging studies that investigated social isolation in healthy subjects. Social isolation correlated with both structural and functional alterations within the social brain network and in other regions that seem to support mentalising and social processes (i.e. hippocampus, insula, ventral striatum and cerebellum). However, results are mixed possibly due to the heterogeneity of methods and study design. Future neuroimaging studies with longitudinal designs are needed to measure the effect of social isolation in experimental v. control groups and to explore its relationship with perceived loneliness, ultimately helping to clarify the neural correlates of the social brain.

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Specialized medial prefrontal-amygdala coordination in other-regarding decision preference

10.1101/640292 ◽

2019 ◽

Author(s):

Olga Dal Monte ◽

Cheng-Chi J. Chu ◽

Nicholas A. Fagan ◽

Steve W. C. Chang

Keyword(s):

Cognitive Processes ◽

Basolateral Amygdala ◽

Brain Regions ◽

Brain Network ◽

Anterior Cingulate ◽

Social Brain ◽

Social Decisions ◽

The Social ◽

Oscillatory Coupling ◽

Other Regarding

AbstractSocial behaviors recruit multiple cognitive processes requiring coordinated interactions among brain regions. Oscillatory coupling provides one mechanism for cortical and subcortical neurons to synchronize their activity. However, it remains unknown how neurons from different nodes in the social brain network interact when making social decisions. We investigated neuronal coupling between the rostral anterior cingulate gyrus of the medial prefrontal cortex and the basolateral amygdala while monkeys expressed context-dependent positive other-regarding preference (ORP) or negative ORP impacting the reward of another monkey. We found an enhanced synchronization between the two nodes for positive ORP, but a suppressed synchronization for negative ORP. These interactions occurred in dedicated frequency channels depending on the area contributing spikes, exhibited a specific directionality of information flow associated with expressing positive ORP, and could be used to decode social decisions. These findings support that specialized coordination in the medial prefrontal-amygdala network underlies social decision preference.

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Interacting brains revisited: A cross-brain network neuroscience perspective

10.1101/2021.02.20.432051 ◽

2021 ◽

Author(s):

C. Gerloff ◽

K. Konrad ◽

D. Bzdok ◽

C. Büsing ◽

V. Reindl

Keyword(s):

Social Behavior ◽

Matrix Decomposition ◽

Brain Regions ◽

Brain Network ◽

Social Characteristics ◽

Neural Basis ◽

Graph Representations ◽

Neural Underpinnings ◽

Nodal Density ◽

Global And Local

AbstractElucidating the neural basis of social behavior is a long-standing challenge in neuroscience. Such endeavors are driven by attempts to extend the isolated perspective on the human brain by considering interacting persons’ brain activities, but a theoretical and computational framework for this purpose is still in its infancy. Here, we posit a comprehensive framework based on bipartite graphs for interbrain networks and address whether they provide meaningful insights into the neural underpinnings of social interactions. First, we show that the nodal density of such graphs exhibits nonrandom properties. While the current analyses mostly rely on global metrics, we encode the regions’ roles via matrix decomposition to obtain an interpretable network representation yielding both global and local insights. With Bayesian modeling, we reveal how synchrony patterns seeded in specific brain regions contribute to global effects. Beyond inferential inquiries, we demonstrate that graph representations can be used to predict individual social characteristics, outperforming functional connectivity estimators for this purpose. In the future, this may provide a means of characterizing individual variations in social behavior or identifying biomarkers for social interaction and disorders.

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Sickness and the social brain: How the immune system regulates behavior across species

Brain Behavior and Evolution ◽

10.1159/000521476 ◽

2021 ◽

Author(s):

Benjamin A. Devlin ◽

Caroline J. Smith ◽

Staci D. Bilbo

Keyword(s):

Immune System ◽

Social Behavior ◽

Brain Regions ◽

Behavior Changes ◽

Social Brain ◽

Evolutionary Origins ◽

Immune Mediators ◽

The Social ◽

Sickness Behaviors ◽

The Brain

Many instances of sickness critically involve the immune system. The immune system talks to the brain in a bi-directional loop. This discourse affords the immune system immense control, such that it can influence behavior and optimize recovery from illness. These behavioral responses to infection are called sickness behaviors and can manifest in many ways, including changes in mood, motivation, or energy. Fascinatingly, most of these changes are conserved across species, and most organisms demonstrate some form of sickness behaviors. One of the most interesting sickness behaviors, and not immediately obvious, is altered sociability. Here, we discuss how the immune system impacts social behavior, by examining the brain regions and immune mediators involved in this process. We first outline how social behavior changes in response to infection in various species. Next, we explore which brain regions control social behavior and their evolutionary origins. Finally, we describe which immune mediators establish the link between illness and social behavior, in the context of both normal development and infection. Overall, we hope to make clear the striking similarities between the mechanisms that facilitate changes in sociability in derived and ancestral vertebrate, as well as invertebrate, species.

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The social brain in female autism: a structural imaging study of twins

Social Cognitive and Affective Neuroscience ◽

10.1093/scan/nsaa064 ◽

2020 ◽

Vol 15 (4) ◽

pp. 423-436

Author(s):

Élodie Cauvet ◽

Annelies van’t Westeinde ◽

Roberto Toro ◽

Ralf Kuja-Halkola ◽

Janina Neufeld ◽

...

Keyword(s):

Sex Differences ◽

Social Cognition ◽

Brain Structure ◽

Imaging Study ◽

Autistic Traits ◽

Brain Regions ◽

Autism Spectrum ◽

Social Brain ◽

Twin Design ◽

The Social

Abstract A female advantage in social cognition (SoC) might contribute to women’s underrepresentation in autism spectrum disorder (ASD). The latter could be underpinned by sex differences in social brain structure. This study investigated the relationship between structural social brain networks and SoC in females and males in relation to ASD and autistic traits in twins. We used a co-twin design in 77 twin pairs (39 female) aged 12.5 to 31.0 years. Twin pairs were discordant or concordant for ASD or autistic traits, discordant or concordant for other neurodevelopmental disorders or concordant for neurotypical development. They underwent structural magnetic resonance imaging and were assessed for SoC using the naturalistic Movie for the Assessment of Social Cognition. Autistic traits predicted reduced SoC capacities predominantly in male twins, despite a comparable extent of autistic traits in each sex, although the association between SoC and autistic traits did not differ significantly between the sexes. Consistently, within-pair associations between SoC and social brain structure revealed that lower SoC ability was associated with increased cortical thickness of several brain regions, particularly in males. Our findings confirm the notion that sex differences in SoC in association with ASD are underpinned by sex differences in brain structure.

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Distinct neural mechanisms of social orienting and mentalizing revealed by independent measures of neural and eye movement typicality

10.1101/726356 ◽

2019 ◽

Author(s):

Michal Ramot ◽

Catherine Walsh ◽

Gabrielle E. Reimann ◽

Alex Martin

Keyword(s):

Eye Movement ◽

Brain Regions ◽

Autism Spectrum ◽

Extensive Study ◽

Neural Systems ◽

Typically Developing ◽

Social Brain ◽

Social Orienting ◽

The Social ◽

Interacting Systems

AbstractExtensive study of typically developing individuals and those on the autism spectrum has identified a large number of brain regions associated with our ability to navigate the social world. Although it is widely appreciated that this so-called ‘social brain’ is composed of distinct, interacting systems, these component parts have yet to be clearly elucidated. Here we used measures of eye movement and neural typicality – based on the degree to which subjects deviated from the norm – while typically developing (N = 62) and individuals with autism (N = 36) watched a large battery of movies depicting social interactions. Our findings provide clear evidence for distinct, but overlapping, neural systems underpinning two major components of the ‘social brain’, social orienting and inferring the mental state of others.

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Mother Brain is Wired for Social Moments

10.1101/2020.05.31.125955 ◽

2020 ◽

Author(s):

Ortal Shimon-Raz ◽

Roy Salomon ◽

Miki Bloch ◽

Gabi Aisenberg Romano ◽

Talma Hendler ◽

...

Keyword(s):

Neural Response ◽

Brain Network ◽

Behavior Patterns ◽

Placebo Administration ◽

Social Brain ◽

Double Blind ◽

Generational Transmission ◽

The Social ◽

Maternal Brain ◽

Brain Behavior

AbstractReorganization of the maternal brain, primed by oxytocin surge during childbirth, triggers the species-typical maternal social behavior. These brief social moments carry profound effects on the infant’s social brain and likely have a distinct signature in the maternal brain. Utilizing a double-blind, oxytocin/placebo administration crossover design, we imaged mothers twice while observing three naturalistic maternal-infant contexts in the home ecology; “unavailable”, “unresponsive”, and “social”, when mothers engaged in synchronous pick-a-boo play. We found four processes by which mother’s brain registers social moments. Salience - social moments increased activations throughout the maternal brain network; Brain-behavior coupling - caregiving behavior linked with socially-driven neural response; Oxytocin sensitivity – administration impacted neural response mainly to the social context; and Temporal engrams–consistent temporal patterns in insula and TP characterized response to social play. Findings describe how mother’s brain compiles and amplifies these precious social moments to generate dyad-specific brain-behavior patterns that initiate the cross-generational transmission of human sociality.

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Heterogeneity of EEG resting-state brain networks in absolute pitch

10.1101/2020.05.03.063206 ◽

2020 ◽

Author(s):

Marielle Greber ◽

Carina Klein ◽

Simon Leipold ◽

Silvano Sele ◽

Lutz Jäncke

Keyword(s):

Functional Connectivity ◽

Auditory Cortex ◽

Resting State ◽

Large Scale ◽

Absolute Pitch ◽

Brain Regions ◽

Brain Network ◽

Higher Order ◽

Neural Basis ◽

Whole Brain

AbstractThe neural basis of absolute pitch (AP), the ability to effortlessly identify a musical tone without an external reference, is poorly understood. One of the key questions is whether perceptual or cognitive processes underlie the phenomenon as both sensory and higher-order brain regions have been associated with AP. One approach to elucidate the neural underpinnings of a specific expertise is the examination of resting-state networks.Thus, in this paper, we report a comprehensive functional network analysis of intracranial resting-state EEG data in a large sample of AP musicians (n = 54) and non-AP musicians (n = 51). We adopted two analysis approaches: First, we applied an ROI-based analysis to examine the connectivity between the auditory cortex and the dorsolateral prefrontal cortex (DLPFC) using several established functional connectivity measures. This analysis is a replication of a previous study which reported increased connectivity between these two regions in AP musicians. Second, we performed a whole-brain network-based analysis on the same functional connectivity measures to gain a more complete picture of the brain regions involved in a possibly large-scale network supporting AP ability.In our sample, the ROI-based analysis did not provide evidence for an AP-specific connectivity increase between the auditory cortex and the DLPFC. In contrast, the whole-brain analysis revealed three networks with increased connectivity in AP musicians comprising nodes in frontal, temporal, subcortical, and occipital areas. Commonalities of the networks were found in both sensory and higher-order brain regions of the perisylvian area. Further research will be needed to confirm these exploratory results.

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Social by Default: Characterizing the Social Functions of the Resting Brain

Current Directions in Psychological Science ◽

10.1177/0963721419857759 ◽

2019 ◽

Vol 28 (4) ◽

pp. 380-386 ◽

Cited By ~ 10

Author(s):

Meghan L. Meyer

Keyword(s):

Social Cognition ◽

Cognitive Neuroscience ◽

Brain Regions ◽

Social Neuroscience ◽

Future Research ◽

Default Network ◽

Social Brain ◽

Social Functions ◽

Neuroscience Research ◽

The Social

Social-neuroscience research has identified a set of medial frontoparietal brain regions that reliably engage during social cognition. At the same time, cognitive-neuroscience research has shown that these regions comprise part of the default network, so named because they reliably activate during mental breaks by default. Although the anatomical similarity between the social brain and the default brain is well documented, why this overlap exists remains a mystery. Does the tendency to engage these regions by default during rest have particular social functions, and if so, what might these be? Here, it is suggested that the default network performs two critical social functions during rest: social priming and social consolidation. These constructs will be defined, recently published empirical findings that support them will be reviewed, and directions for future research on the topic will be proposed.

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