BEHAVIORAL and Neural ASSESSMENT of Implicit and Explicit SOCIAL Cognition In AUTISM

Background:  

Understanding the mental states of others (social cognition) plays a key role in the adequate reaction to other people’s behaviour. Standard social cognition tasks to date, however, often employ stimuli such as written stories or comics that are less vivid and rich than our real social environment. Although these tasks have proven sensitive in detecting social cognition difficulties in individuals with autism spectrum consitions (ASC), they do not allow generalization to real life social settings. 

Objectives:

To develop two new movie-based behavioral tasks for the assessment of implicit and explicit social cognition and to adapt the more naturalistic task design to the fMRI environment.

Methods:  

For the behavioural tasks we produced a new set of stimuli comprising film scenes (20-35s) displaying social interactions. In the implicit task, participants watch a social film scene and are then asked to select how the film will proceed out of four short film clips (4 s). In the explicit task, participants first watch a film scene and are then asked to pick one out of four text options that correctly describes the mental state of one protagonist. We adapted the explicit task for fMRI. 

Results:  

Preliminary reliability analysis of the behavioural tasks (N(ASD) = 9, N(NT) = 9) yielded for the implicit task a mean item difficulty of .69 (SD = .16) and a satisfactory reliability of .73 (Cronbach’s alpha). In the explicit task the mean item difficulty was .65 (SD = .14) and reliability was .77 (Cronbach’s alpha). Although there were no significant performance differences between ASD and NT in both tasks, which is likely due to small sample size, individuals with ASD showed trendwise significantly increased reaction times for the implicit task (ASD: 40.7s (SD = 11.04); NT: 32.0s (SD = 3.2); p = .055).

Preliminary fMRI analysis showed that the naturalistic task design robustly activated the mentalizing network in NT (e.g. bilateral superior temporal sulcus (STS), temporal parietal junction (TPJ), temporal poles), where this network furthermore correlated with performance in the social cognition task in both groups. We found significant group differences (NT > ASD) within these mentalizing regions. Finally, the naturalistic social cognition scanner task activated the mentalizing network more robustly than a comparable pictorial social cognition paradigm.

Conclusions:  

The newly developed naturalistic social cognition tasks are well suited for the assessment of social cognition on the behavioural and brain level.