The use of habituation in the study of the effects of infantile malnutrition.

Habituation of the orienting response (OR) was used to assess possible attentional deficits associated with infantile malnutrition. The procedure involved the presentation of 40 trials of a pure tone stimulus to 8 marginally nourished and 8 malnourished 13 1/2-month-old male infants. The results showed that the initial OR to stimulus onset, as measured by the magnitude of cardiac deceleration, was significantly larger in marginally nourished than in malnourished infants. Within-group comparisons revealed that marginally nourished infants showed significant increases in OR magnitude to changes in tonal frequency whereas the malnourished infants did not. The results were taken as evidence of an attentional deficit associated with infantile malnutrition that is likely to interfere with subsequent learning.