Sofie L. Valk | The structure of the social brain

Background. Social behaviour is at the core of what makes us human and it is closely linked to mental health. Previous developmental, clinical, and neuroimaging studies have shown that affective forms of understanding others (such as compassion and empathy) and their cognitive counterparts (Theory of Mind) are likely related to different functional brain systems. However, it is not completely understood how social behaviour is supported by brain structure, and to what extent training of socio-affective and socio-cognitive skills affects brain structure.

Methods. We carried out the following experiments. 1) We related individual differences in empathy and cognitive perspective-taking constructs to variability in cortico-cortical structural networks in healthy individuals; 2) We tracked plasticity in grey matter following socio-affective and socio-cognitive training and related grey matter change to the behavioural impact of the training; 3) We investigated the dissociability of affective and cognitive social functioning in the context of disease, by comparing structural networks of subjects with alexithymia (a subclinical trait associated to atypical interoception and empathy) and autism spectrum disorder (a group of neurodevelopmental conditions associated with difficulties in Theory of Mind); 4) In a multi-site study we assessed the consistency of structural alterations in cortical thickness in patients with autism spectrum disorder at a regional and network level.

Results. We found that individual differences in empathy are related to structural networks centred on the insular cortex, whereas differences in perspective-taking are related to those centred on medial frontal- and temporo-parietal cortices. Further on the training of these capacities resulted in specific cortical thickness changes, which were also predictive of behavioural improvements in the corresponding domains. Studies in clinical populations revealed an effect of alexithymia on networks centred on the insular cortex, whereas autism diagnosis related to disrupted networks centred on frontal and temporo-parietal cortices.

Significance. Our experiments indicate that socio-affective and socio-cognitive capacities are associated with independent and specific assemblies of neocortical regions, indicating a dissociation of these capacities at the neuroanatomical level. Furthermore, our findings provide evidence for a potential biological basis for how social intelligence can be fostered in healthy adults. Future research will be needed to investigate the utility of these different types of training in the context of pathologies, such as autism spectrum disorder or psychopathy, and whether these trainings can be used to nourish soft-skills and social intelligence in children, with the overall goal of improving social engagement and well-being.

Poster