Question

Why do you think enrichment ‘equalizes’ maze performance in rats? Apply the principles of epigenetics in your explanation. How can we apply the findings on enrichment to human populations? How do these findings relate to Turkheimer’s research on the heritability of IQ among impoverished populations?

Answer 1

Environmental Enrichment is the act of simulating the brain by both physical and social surrounding. Enrichment experiments performed on rats suggested that even though the young enriched rats perfromed better than the aged enriched rats, but the aged enriched rats outperformed the aged non - enriched rats on all behavioural measures and in some cases even young non - enriched rats also. Thus enrichment leads to increased ability to acquire and use the spatial information along with neurogenesis. Thus leading to equalizing effect through new cell survival.

Enrichment can help in rehabilitation of indivisuals suffering from neurodegenerative diseases like Alzheimer's disease, Parkinson' disease, Huntington's disease etc. Children with autism show improvement in cognitive abilities after enrichment. Lead poisioning during gestation period leads to low spatial learning. The effects can be overturned using enrichment.

Turkheimer's research was based on the heritability of IQ in families with high socioeconimic status(SES) and low SES. Following were the observations

1. Low SES
   • Children had similar IQ, regardless of genetic similarity.
   • Variance was accounted to environmental factors, genes playing no role.
2. High SES
   • Monozygotic twins had similar IQ, dizygotic twins' IQ scores varied.
   • Family environment didn't have much role to play

Finally it was concluded that hertability of IQ for a large and diverse population is of little sense. Heritability varies depending on the population and environment under observation.