Embryonic and early post-natal development are crucial periods in determining the expression of certain traits in an organism. Environmental factors can influence crucial periods of development, these factors can be physical (things such as chemicals, nutrition, radiation, ect...) and positive (the presence of something causing harm) or negative (a lack of something can cause harm too). Today I would like to present a negative-nutritional affect in post-natal development dealing specifically with cell proliferation in the hippocampus of mammals and how it relates to cognitive impairments and disorders.Or more simply, how malnutrition in babies (humans or rats) leads to slowed learning, depression, and schizophrenia.
This study focused specifically on an observed phenomena that mammals reared in an environment lacking proper nutrition often have a higher frequency of sub-average cognitive abilities. The study worked at answering whether this phenomena was due to cell differentiation or cell proliferation being stopped.
The study found malnutrition works by stopping proliferation not differentiation. The study came to this conclusion based on variations in their experimental design that boosted the malnourished rats nutrition, which allowed them to make a almost full recovery, both the recovered and well fed rats expressed more of a particular type of neuron however, had the same number of types. If cell differentiation had been the cause, this could not have happened because when given more nourishment one should have seen an increase in types of cells (not to mention if it was due to cell differentiation, one could have just used the number of types of cells from the initial two groups). The study concluded by speculating that the depression and schizophrenia associated with malnutrition is probably due to the recovery stage (when nutrition is available) increasing cell proliferation and delaying neurogenesis which results in neurons that are not trimmed to function.
This article is extremely detailed, if you are interested, you should read up.