Sensory restriction and isolation experiences in children with phenylketonuria.

2 groups of children with phenylketonuria, those with a history of early sensory restriction or isolation and those without, were compared on measures of (a) interpersonal behavior, (b) language comprehension, (c) intelligence, and (d) incidence and severity of personality disturbances. The findings, discussed in the context of sensory-deprivation and sensory-restriction research, supported the hypothesis that early alterations in the child's sensory environment lead to later impairment in interpersonal, emotional, and intellectual functioning. The degree of this impairment was found to be related to the age of the child at the time of the early stress experience, but not to the duration of sensory restriction or isolation.