Vestibular hyporeactivity in infants at risk for schizophrenia. Association with critical developmental disorders.

Vestibular responses to caloric stimulation were measured from birth to age 2 years in ten infants born to schizophrenic mothers. This is part of a study of evolving neurointegrative disorders that may be associated with a genetic risk for schizophrenia. Transiently decreased vestibular responses coincided with several developmental disorders that were related to psychopathology at 10 years. Absent to decreased responses were associated with (1) a "pandevelopmental retardation" involving physical growth as well as postural-motor and visual-motor development, (2) an "abnormally quiet" state in the first month, and (3) failures of bimanual integration between 4 and 6 months. The transitory nature of the decreased nystagmus rules out the possibility of an organic lesion of the vestibular system. Rather, it suggests that some covert decrease in arousal accompanied those periods when central nervous system integration was disrupted.