In summary, in the process of exploring the neonates' behavioral and autonomic repertoire for the purpose of devising techniques that would enable us to measure temperamental differences, we have come across two phenomena that we would like to emphasize. First we described the neonate's ability to habituate his responses to sensory stimuli and pointed out its possible relations to the neurophysiological structure subserving arousal, inhibition and attention; second we demonstrated that neonates have the capacity for sensory discrimination but noted that this primitive discrimination and habituation need not be dependent on the functioning of cerebral cortex and does not appear to be identical with the same phenomena in the mature organism.Abstract Teaser