The clinical and etiological relationship between autism spectrum disorder (ASD), schizophrenia, and bipolar disorder is not clear. The extent to which they share causal bases has important implications for clinicians, researchers, and for the people suffering from these disorders.
The autonomic nervous system seems increasingly able to reveal early our characteristics and our psychic vulnerabilities: the pupillary light reflex and alpha-amylase secretion in saliva have recently been indicated as potential indicators of autistic disorder since the twentieth month of life.