Amygdala connectivity during involuntary attention to emotional faces in typical development and autism spectrum disorders

Involuntary attention to faces is a behavior seen from birth and is a key factor underlying the development of social skills. Maturation of social skills continues through increased regulation of involuntary attention to social stimuli. Autism Spectrum Disorders (ASD) are neurodevelopmental disorders typified by inattention to faces and poor development of social skills. It has been hypothesized that abnormal activity of the amygdala, a region thought to respond to salience, may underlie abnormal social attention in ASD. However, the relationship between amygdala activity and involuntary attention to social stimuli is unclear, particularly in the context of developing social skill. To investigate these relationships, this dissertation describes three studies conducted evaluating the relationship between functional connectivity (FC) of the amygdala and involuntary attention to faces. The first study investigated amygdala FC during involuntary attentional orienting to emotional faces from late childhood through late adolescence, to better understand the relationship between amygdala FC and the development of mature social attention. Results found that amygdala FC with cognitive control regions increased with age, while FC with attentional orienting and emotion processing regions decreased with age. Results also showed a developmental shift from increased amygdala FC for negative stimuli in late childhood to increased amygdala FC for positive stimuli in late adolescence. The second study investigated amygdala FC during involuntary attentional orienting to emotional faces in children with ASD. Results found that amygdala FC was increased with cognitive control regions during orienting to both positive and negative emotions, but that FC with attentional orienting and emotion processing regions differed by valence. The third study investigated amygdala FC during the conscious inhibition of involuntary attention to emotional faces in children with ASD. This study demonstrated that amygdala FC with cognitive control and emotion processing regions was increased in children with ASD during inhibition of attention to facial stimuli. Together these studies show that effective FC between the amygdala and cognitive control regions leads to better regulation of involuntary attention to emotional faces, while ineffective FC between amygdala and cognitive control regions may account for abnormal social attention in ASD.