Poster #14 - Developmental Changes in Brain Functional Connectivity During Social Interaction in Middle Childhood

• In Event: 2-110 - Poster Session 07
  In Poster Session: PS 07 Section - Biological Processes: Neuroscience and Genetics

Integrative Statement

Introduction
Mentalizing, the ability to infer one’s own and others’ mental states, is crucial to successful social interaction. Recent explorations of the neural basis of social interaction have implicated both mentalizing and reward regions (Pfeiffer et al., 2014; Redcay et al., 2010; Rice and Redcay, 2016). However, few have examined this in middle childhood (Alkire et al., 2018; Warnell et al., 2018), an important period for social development and no research has examined how social interaction modulates brain functional connectivity. Because a region’s function is in part determined by its connections, an understanding of network organization is important in understanding the development of social interaction. Specifically, we predicted that functional connectivity would change within and between mentalizing and reward networks during social interactions as peers become increasingly important in children’s social worlds.

Methods
Forty-seven children (27 males, 10.31 ± 1.31 years, range 8.18-12.98 years) were included in the analysis. We used an interactive game in which children either chatted with a peer or answered questions about a story character (Alkire et al., 2018). To examine effects of mental state reasoning and social interaction, we used a 2*2 event-related design with factors of mental (Mental and Non-Mental) and social interaction (Peer and Character). The task included 4 runs and 96 trials (24 trials per condition).

Data preprocessing was performed using a standard procedure by AFNI (Cox, 1996), with functional images normalized to a child template (Fonov et al., 2011) and effects of head motion minimized (i.e., censor volumes exceeding 1 mm framewise displacement (FD); remove runs >10% censor or mean FD>0.5 mm). Controlling for residual head motion, functional connectivity was calculated using the Mumford et al. (2012) approach. We correlated trial-wise beta series from mentalizing and reward regions (Neurosynth; Yarkoni et al., 2011) for each condition (Figure. 1). We examined interactions with age and the main effects of social interaction and mental on the mean connectivity within and between networks in separate regression models.

Results
We observed a significant interaction between age and social interaction on mean connectivity within and between reward and mentalizing networks (but no interaction with mental). To further probe this interaction, we divided the sample by the median of age of 10.25 years (24 younger and 23 older children). We found a similar trend of social interaction (peer > character) on mean connectivity within and between mentalizing and reward networks in older child group, but only connectivity within the mentalizing network reached significance (F(1, 22) = 4.28, p = .044; Figure. 2).

Conclusion
We demonstrate age-related differences in connectivity within and between mentalizing and reward networks when children make predictions about a social partner compared to a story character. Specifically, children in later childhood/early adolescence demonstrated significantly greater connectivity within the mentalizing network when engaging with the peer than reasoning about a character. These data suggest that functional changes within the mentalizing network may relate to increasing sensitivity to social interactions during emerging adolescence.

Authors

• Yaqiong Xiao, University of Maryland, College Park
  Presenting Author

• Diana Alkire, University of Maryland, College Park
  Non-Presenting Author

• Dustin Moraczewski, University of Maryland, College Park
  Non-Presenting Author

• Elizabeth Redcay, University of Maryland
  Non-Presenting Author