Stimulation in the NICU: is more necessarily better?

Animal studies and studies with human full-term infants suggest that the stimulation present in utero affects postnatal preferences and levels of response. The premature infant does not necessarily benefit from a re-creation of the in utero environment. Each aspect of the in utero environment should be assessed independently as a potential source of added stimulation in the NICU to determine its possible effects on the development of the premature infant. The NICU environment cannot be accurately labeled by global descriptors of "deprivation" or "overstimulation." When compared with the home environments of full-term infants from lower SES homes, different aspects of the NICU environment were recorded more often, less often, or equally as often as in the full-term infants' homes. Baseline levels of stimulation should be recorded in any NICU environment prior to the institution of an intervention program. NICU caregivers tended to respond contingently to their premature patients' behaviors. However, the prematures provided few opportunities for the nurses to respond, when visual and vocal behaviors used by full-term infants were employed as the expected norm. Perhaps both the medical staff and parents should be trained to recognize and respond to the more subtle, different cues described by Als et al. as being prevalent in the behavioral repertoire of the premature infant. Based on ecologic descriptions of NICU's, researchers have suggested that an inappropriate pattern of stimulation may characterize the environment, rather than an inappropriate amount of stimulation. The NICU environment has been characterized as providing little cross-modal stimulation, few temporally patterned stimuli, and little diurnal rhythmicity. In addition, the premature infant may have few opportunities to control the environment, contrary to the full-term infant's experiences. There is evidence of some negative effects of added NICU stimulation. Individual infants should be assessed prior to intervention for their level of behavioral maturation. Interventions should be individualized for the particular needs of each infant, rather than subjecting all infants assigned to a treatment condition with a stimulation "package." The worthy goal of promoting the development of premature infants carries with it the responsibility of ensuring that no harmful effects could befall any one infant.