The aim of this article was to investigate the relationship between the characteristics of behavioral pattern and of autonomic reactivity in autism.

In study I, one hundred and eleven autism's data based on their trainers' observation were analysed to extract some behavioral characteristics in autism. Six factors were extracted. They were named respectively as deficiency of communication, hypersensitivity in hearing, seeking tendency for primary sensation, stereotyped and repetitive behavior, lack of interpersonal relationship and hypoactivity.

Study II focused on the relationship between these behavioral characteristics and the autonomic reactivity observed in heart rate level. Twenty three autism were devided into the two groups (high HR and normal HR) based on their HR level in base line period. High HR group showed above 90 bpm. This group was considered as a group of hyper autonomic reactivity. The significant differences between two groups were observed only in two behavioral characteristics, deficiency of communication and hypoactivity. There were no difference between high HR group and normal HR group on other four behavioral characteristics.