Gastrointestinal disorders observed in autistic children prompted a series of related investigations of biological abnormalities. TCDC electrophysiologic recordings, histamine wheal response tests, eosinophile counts, blood cortisol determinations, and behavioral observations involving 15 autistic children were conducted to study several interrelationships, particularly malabsorption and cerebral dysfunction. Control subjects included siblings, other normal children, and normal, schizophrenic and nonschizophrenic adults. Observed differences tended to support approaches that distinguish autism from the large majority of “the schizophrenias.” Characteristic “DC bursts” were found in autistic children, suggesting a maturational failure of a brain control system. Abnormal response of their TCDC system to gliadin and cortisol postulated an underlying cerebral defect affected by stress, diet, or other chemical change. Conclusions imply a fundamental neurobiological dysfunction in “childhood autism,” its possible correlation with malabsorption, and mutual compatibility of various other approaches to etiology.