Behavioral changes in nonambulatory, profoundly mentally retarded individuals.

Abstract

Nonambulatory, profoundly mentally retarded (NPMR) individuals seldom have been studied as a distinct population. This investigation sought to describe the pshysical, etiological, and behavioral characteristics of NPMR children and adults and to evaluate the effects of intensive physical and social stimulation on their ongoing behavior. Sixteen NPMR subjects were studied for 2 1/2 years. All were PMR, bedridden, abnormally small, and unresponsive to external stimulation. Baseline data concerning developmental status, diurnal patterns of sleep and activity, behavior in a novel situation, ongoing ward behavior, and anthropometric measures were obtained. Subjects were highly variable in their responses to items from the Bayley Scales of Infant Development, with overall performance below that of a normal six month old. Although subjects showed some diurnal pattern of sleep, they frequently fell asleep for short periods at random time during the day. In a novel situation subjects responded minimally to stimulus objects, or not at all. Typically, their ongoing ward behavior consisted of very low level activity, involving small peripheral limb movements, wandering or blinking eyes, mouthing or grimacing, and repetitive, reflexive types of patterns labeled "fixed action sequences." Experimental treatment consisted of three phases of daily stimulation. (1) Subjects were placed in an upright or elevated position in specially constructed "playpens." (2) Subjects were placed in "playpens" and many toys were presented. (3) Subjects were positioned in pairs so that direct physical contact was provided. Each phase resulted in changed behavioral profiles during treatment. Furthermore, all experimental subjects showed beneficial effects of treatment in their ongoing ward behavior, diurnal sleep patterns, Bayley performance, or response to novel situations. Implications of this research extend to understanding environmentally induced changes in neurological maturation and social development in individuals previously thought to be hopelessly devastated. The descriptive data are intended to provide a useful framework for further systematic research with NPMR populations.