Autonomic responses of autistic children to people and objects

Several recent lines of inquiry have pointed to the amygdala as a potential lesion site in autism. Because Several recent lilies of inquiry have point ed to the amy one function of the amygdala max, be to produce autonomic aro usal at the sight of a significant face, we compared the responses of autis tic children to their mothers' face and to a plain paper cup. Unlike normal s, the autistic children as a whole did not show a larger response to the p erson than to the cup. We also monitored sympathetic activity in autistic c hildren as they engaged in a wide range of everyday behaviours. The childre n tended to use self-stimulation activities in order to calm hyper-responsi ve activity of the sympathetic ("fight or flight") branch of the autonomic nervous system. A small percentage of our autistic subjects had hyporespons ive sympathetic activity, with essentially no electrodermal responses excep t to self-injurious behaviour. We sketch a hypothesis about autism accordin g to which autistic children use overt behaviour in order to control a malf unctioning autonomic nervous system and suggest that they have learned to a void using certain processing areas in the temporal lobes.