Relating to the Learning of Children Identified as Having Experienced Malnutrition

Described was research on the behavioral and learning effects of lead poisoning or malnutrition in rats. It is explained that approximately 200 rats (either weanling, adult, pregnant, or nursing) were injected with various amounts of lead. It was found that symtomatic levels of lead in weanling or adult rats produced no obvious behavioral or learning impairments, though asymptomatic doses of lead produced a 100% abortion rate in pregnant rats and retarded development and learning impairments in the offspring of lactating rats. The author describes a completely automated closed-field maze series for rats developed to counter inaccuracies among observers using a conventional maze. It is reported that experiments with 130 rats to determine the cause of pica (the voluntary ingestion of lead by children) showed that calcium-deficient rats ingested significantly more lead than non-deficient or iron-deficient fats. Experiments attempting to produce picas in adult rats by conditioning procedures were said to have negative results. The most severe effects of protein malnutrition on learning ability were found to occur when the malnutrition was imposed prenatally. (DB)