A new study of neuroimaging results of people from the United Kingdom compared members of sports teams, religious groups, social clubs and people reporting not participating in any of these types of groups. Results showed that functional connectivity of default mode and limbic networks of the brain differed between people reporting participation in these three types of social groups and those who did not. The study was published in the Cerebral Cortex.
Humans are social beings. Belonging to social groups is one of the basic emotional needs people have. It is crucial for a person’s mental health and well-being. Studies have shown that people who experience social isolation and disconnectedness tend to also report lower levels of physical health. Interpersonal interaction in social groups is the primary mechanism that creates the structure of our society.
“Experiencing the team spirit in a vibrant soccer match, enjoying a beer in a bar with like-minded persons, or resting in collective silent prayer—these are formative experiences that scaffold human social life,” said the authors of the current study.
But do brain activity patterns and structures differ between people who regularly engage in social activities and those that do not? Brain networks that were of particular interest to researchers with regard to this question were the default mode network and the limbic network.
The default mode network is a large network of brain cells that increases its activity when the person is not focused on the outside world and is at rest while being awake. It consists of brain cells located in the dorsal medial prefrontal cortex, posterior cingulate cortex/precuneus, and angular gyrus regions of the brain.
The limbic network is a network of higher brain functions involved in emotions and episodic memory and is composed of the hypothalamus, hippocampus, mammillary body, thalamus, cingulate gyrus, parahippocampal gyrus and the entorhinal cortex regions of the brain.
Study author Carolin Kieckhaefer and her colleagues wanted to explore whether brains of people who regularly participate in social groups differ in structure and connectivity from brains of people who do not. They analyzed data of 40.000 persons included in the UK Biobank database for whom magnetic resonance imaging measures were available and who also answered the question about whether they participate in activities of sports teams, religious groups or social clubs at least once a week or more often (“Which of the following do you attend once a week or more often?”).
When sports team activities were considered, authors report that they “found regions of the default and limbic network as well as lingual gyrus, prefrontal, and temporal cortexes to be the key brain correlates linked to weekly engagement in a sports team.”
Results showed that volume variations of the limbic network, somato-motor network and the default mode network were associated with participation in religious groups. “The prominent effect with greatest uncertainty was seen in the limbic network, while the most certain network-level volume effect was located to the default mode network.”, study authors report.
Participation in social clubs was linked to activities of the limbic network, but authors list the most informative brain networks for social club attendance were the visual network, closely followed by the default mode network.
“The regular attendees of sports teams showed wide-ranging deviations in the intranetwork connectivity of default and limbic networks,” the researchers said. “People participating in religious groups in turn were especially characterized by a compounding of within-network functional connections within the default mode network, limbic network, and to some extent also in the frontoparietal control network.”
“In contrast to these 2 types of social participation, social participation in social clubs did not lead to a salient increase of functional connectivity strengths within most of the aforementioned networks. Instead, a relevant decrease in functional connectivity was noted within the default mode network and limbic networks as the single most coherent pattern of deviation.”
“Among all 3 examined types of groups, we identified the default mode network and limbic network as central for social participation,” the researchers concluded.
The study sheds light on the neural correlates of social participation. However, it also has limitations that need to be taken into account. Notably, social participation was measured using only one short question and it was a self-report. Studies that used more detailed measure of social participation might not produce identical results.
The study, “Social belonging: brain structure and function is linked to membership in sports teams, religious groups, and social clubs”, was authored by Carolin Kieckhaefer, Leonhard Schilbach, and Danilo Bzdok.