Consistent neural activity patterns represent personally familiar people

Stimuli, behavioral data, preprocessed neural data, and presentation and analysis code from: Thornton & Mitchell (submitted) Patterns of neural activity distinguish representations of familiar people. Raw imaging data can be accessed online at the Harvard Dataverse: http://dx.doi.org/10.7910/DVN/ZQQAB

Response patterns in the developing social brain are organized by social and emotion features and disrupted in children diagnosed with autism spectrum disorder

© 2019 Elsevier Ltd Adults and children recruit a specific network of brain regions when engaged in “Theory of Mind” (ToM) reasoning. Recently, fMRI studies of adults have used multivariate analyses to provide a deeper characterization of responses in these regions. These analyses characterize representational distinctions within the social domain, rather than comparing responses across preferred (social) and non-preferred stimuli. Here, we conducted opportunistic multivariate analyses in two previously collected datasets (Experiment 1: n = 20 5–11 year old children and n = 37 adults; Experiment 2: n = 76 neurotypical and n = 29 5–12 year old children diagnosed with Autism Spectrum Disorder (ASD)) in order to characterize the structure of representations in the developing social brain, and in order to discover if this structure is disrupted in ASD. Children listened to stories that described characters' mental states (Mental), non-mentalistic social information (Social), and causal events in the environment (Physical), while undergoing fMRI. We measured the extent to which neural responses in ToM brain regions were organized according to two ToM-relevant models: 1) a condition model, which reflected the experimenter-generated condition labels, and 2) a data-driven emotion model, which organized stimuli according to their emotion content. We additionally constructed two control models based on linguistic and narrative features of the stories. In both experiments, the two ToM-relevant models outperformed the control models. The fit of the condition model increased with age in neurotypical children. Moreover, the fit of the condition model to neural response patterns was reduced in the RTPJ in children diagnosed with ASD. These results provide a first glimpse into the conceptual structure of information in ToM brain regions in childhood, and suggest that there are real, stable features that predict responses in these regions in children. Multivariate analyses are a promising approach for sensitively measuring conceptual and neural developmental change and individual differences in ToM.NSF (Award 1122374

Neural and Psychological Coordination in Social Communication and Interaction

Dynamic, naturalistic study of social interactions in humans is a small but growing literature. Emerging from this work is the theory that social interaction creates a “merged mind” between interlocutors – they come into psychological, behavioral, and neural alignment in order to better predict each other and coordinate as one social unit. However social interaction is diverse, so more work is needed to understand the specific nature of alignment between people in a variety of interactive contexts. In particular, it’s unclear how heterogeneities among members of an interaction impact their ability to align. This work aims to help address this gap by first evaluating and improving ways to collect neuroimaging data in naturalistic, social settings (Chapter 2). Then, empirical research is presented that examines how personal similarity factors impact the extent of alignment during personal disclosure interactions, where one person speaks and the other listens (Chapter 3). Finally, further empirical research investigates different types of alignment that may be present in a dyadic back-and-forth discussion in a joint decision-making paradigm. How this work contributes to a broader understanding of the ways people communicate and work together, and how this research can continue with improved methods, is discussed

Learning About Others Dynamically Changes Behavior And The Brain

Humans are social beings. The ability to interact socially requires associating perceptual and social information about other people. While prior work has elucidated the cognitive and neural basis of general social knowledge, less is known about how person-specific information is learned and remembered. The goal of this dissertation was to explore how learning associations between visual and abstract information could influence conceptual representations of specific individuals. Across three studies people learned social and reward values associated with different faces. Chapter 2 examined how the learned values influenced explicit judgments by measuring behavioral face similarity spaces before and after learning. While pre-learning spaces were structured by the visual similarity of the faces, social values selectively determined the post-learning spatial organization, and generalized to expectations of behavior in a future social context. Chapter 3 investigated the neural correlates of the face-value associations. Using functional magnetic resonance imaging (fMRI), brain activity patterns were measured while participants viewed faces and performed a task unrelated to the values, once before and once after learning. A region in the left anterior temporal lobe (ATL) had activity patterns that were biased by the social values after learning, such that faces of more similar social values evoked more similar activity patterns, and the magnitude of these learning-induced changes was directly related to an individual’s learning performance as a function of value type. Additionally, activity pattern similarity in the left inferior parietal lobe (IPL) tracked the spatial organization of individual behavioral similarity spaces after learning. Chapter 4 assessed whether there were perceptual consequences of such behavioral and neural modulations and whether effects were domain-general. A categorical perception paradigm was used to test whether learned values implicitly influenced face discrimination. Preliminary evidence indicated that both social and reward values affected discrimination performance for face and flower stimuli, however the effect of social values did not persist over a long-term delay and was susceptible to task order effects. Together, this work indicates that learned associations between visual and social attributes of other people can warp behavioral and neural representations, and such changes have downstream consequences on face perception and social preferences