Theory of Minds: Managing mental state inferences in working memory is associated with the dorsomedial subsystem of the default network and social integration

Abstract

We often interact with multiple people at a time and consider their various points-of-view to facilitate smooth social interaction. Yet, how our brains track multiple mental states at once, and whether skill in this domain links to navigating real-world social interactions, remains underspecified. To fill this gap, we developed a novel social working memory paradigm in which participants manage two- or four-people’s mental states in working memory, as well as control trials in which they alphabetize two- or four-people’s names in working memory. In Study 1, we found that the dorsomedial subsystem of the default network shows relative increases in activity with more mental states managed in working memory. In contrast, this subsystem shows relative decreases in activity with more non-mental state information (the number of names alphabetized) managed in working memory. In Study 2, only individual differences in managing mental states in working memory, specifically on trials that posed the greatest mental state load to working memory, correlated with social network integration. Collectively, these findings add further support to the hypothesis that social working memory relies on partially distinct brain systems and may be a key ingredient to success in a social world.

Neurocognitive mechanisms of poor social connection in posttraumatic stress disorder: Evidence for abnormalities in social working memory

“…Our sample was heterogenous in terms of index trauma type, which increases generalizability but does not allow for close examination of whether trauma type, such as interpersonal versus noninterpersonal trauma, has particularly strong associations with SWM and social connection. As previously described (Meyer & Collier, 2020), while our calculation of task accuracy assumes that all relationship partners' mental states impact each other equally, relationship partners likely impact each other's mental states to different degrees, for example, as a function of the importance of the relationship or the frequency of contact.…”

“…Greater recruitment of the dorsomedial subsystem supports better SWM, which is in turn associated with better social skills and more social integration (Meyer & Collier, 2020; Meyer et al, 2012; Meyer, Taylor, et al, 2015). We found that individuals with PTSD exhibited hyperactivation within this subsystem, but also poorer accuracy on four‐load trials compared to trauma‐exposed controls—which we speculate may indicate that those with PTSD exert more cognitive effort when inferring others' mental states.…”

“…SWM refers to the maintenance and manipulation of information about people's mental states, personalities, and relationships on a moment‐to‐moment basis (Meyer & Lieberman, 2012; Meyer et al, 2012; Meyer, Taylor, et al, 2015). SWM preferentially engages the brain's default network: brain regions in this network increase activity as a function of the amount of social information managed in working memory (i.e., SWM “load”; Meyer & Collier, 2020; Meyer & Lieberman, 2012; Meyer, Taylor, et al, 2015). Moreover, in neurotypical samples, greater default network activity in response to SWM load correlates with social skills that are compromised in PTSD, including empathy and perspective‐taking (Mazza et al, 2012; Meyer et al, 2012; Meyer, Taylor, et al, 2015; Moore et al, 2017).…”

“…Moreover, in neurotypical samples, greater default network activity in response to SWM load correlates with social skills that are compromised in PTSD, including empathy and perspective‐taking (Mazza et al, 2012; Meyer et al, 2012; Meyer, Taylor, et al, 2015; Moore et al, 2017). Additionally, individual differences in SWM have been linked to social network size (Krol et al, 2018; Meyer & Collier, 2020). Collectively, these studies suggest that individuals with PTSD may show altered responses in the default network while managing demands to SWM, which may help explain their poor social connection.…”