These preliminary results are of interest in that they relate a biochemical abnormality similar to the one found in schizophrenia to social isolation and an experimental lack of tactile stimulation in early life. It is important to note that in this study the biochemical defect was found not to be correlated closely with disturbed behavior, indicating amongst other things that the complexities of behavior probably have many other antecedents besides biochemical maladaptation.Such antecedents must almost certainly include patterns of behavior learned from whatever models were available in the environment during psychologic maturation. Hopefully in future studies it will be possible to manipulate both these sets of variables with some precision. The interaction of biologic or general somatic factors, and psychologic or learned factors, in the origins of disturbed behavior has always been a central issue for psychiatry. The present study may enable these problems to be approached using primates as an experimental model.From the biologic point of view alone it would probably be very worthwhile to investigate the type, timing and intensity of stimulation necessary to produce the effect discussed in this paper. For instance is stimulation of certain areas of skin, such as the oral or genital areas, especially important? And what about other types of stimulation–proprioceptive, vestibular, visual or auditory? Is it possible that more complex experiences are significant such as the affective components of the perception of objects, or the learning of patterned responses? The scientific manipulation of both biologic and psychologic variables in a monkey colony might give answers to these questions, and to many others still unasked.Abstract Teaser