There is a lack of neuroimaging studies investigating the neuronal mechanisms of Theory of Mind (ToM) processes under close to real-life conditions in individuals with autism spectrum conditions (ASC). We have previously developed a more naturalistic, video-based measure of ToM, the “Movie for the Assessement of Social Cognition” (MASC) that requires participants to infer mental states of movie characters.
To develop an fMRI adaptation of the MASC and to compare brain activation of adults with ASC and matched controls during this naturalistic social cognition task.
In this study, 14 high-functioning adults with ASC and 14 controls matched for age, gender, and IQ underwent fMRI scanning. Participants watched 11 consecutive scenes of the MASC 3 times under 1.) a ToM, 2.) a physical inference (PI), and 3.) a free viewing (FV) condition. Under the ToM and PI conditions, questions concerning the actors’ mental states and concerning physical entities of the scene, respectively, were asked. During the FV condition, participants were asked to watch the scenes without specific task instructions.
A conjunction analysis of the contrast ToM and PI showed that under more naturalistic conditions both the ASC and the control group activated a previously identified ToM network encompassing the temporal pole, superior temporal sulcus and medial prefrontal cortex bilaterally. During the FV condition the ASC group showed a greater increase in fMRI signal in the amygdala than the control group. Notably amygdala activation was negatively correlated with emotion regulation (measured with Emotional experience scales; SEE) in both groups (r = -0.46, p = 0.05).
Under conditions close to everyday life demands, individuals with ASC show greater activation of the amygdala than normal controls, which might be a correlate of emotion regulation in naturalistic social settings and which might lend further support to an amygdala theory of autism.