“…Although most of these studies have found associations between early malnutrition and deficient mental de velopment, an alternative causal explanation for these findings has alw'itys existed. Poverty and accompanying social deprivation almost invariably co exist with malnutrition (e.g., Chase and Martin, 1970;Chavez et at., 1974;Cravioto and Robles, 1965;Evans et at., 1971;Monckeberg et aI., 1972;Mora et at., 1974;Patel, 1974;Schlenker et at., 1968;Smythe, 1963, 1967). Since social deprivation may well playa causal role in deficient mental development (e.g., Hess et at., 1968;Whiteman and Deutsch, 1968), the effects of nutritional and social variables on mental development are confounded.…”