Hobo Girl at Anthroforum points me to new research on how semi-inheritable epigenetic alters the psyche. The source being at Technology Review.
It reviews two recent researches:
In Feig's study, mice genetically engineered to have memory problems were raised in an enriched environment--given toys, exercise, and social interaction--for two weeks during adolescence. The animals' memory improved--an unsurprising finding, given that enrichment has been previously shown to boost brain function. The mice were then returned to normal conditions, where they grew up and had offspring. This next generation of mice also had better memory, despite having the genetic defect and never having been exposed to the enriched environment.Nevertheless they lost the epigenetic improvement after few months of lack of stimulation.
In a second study, researchers found that rats raised by stressed mothers that neglected and physically abused their offspring showed specific epigenetic modifications to their DNA. The abused mice grew up to be poor mothers, and appeared to pass down these changes to their offspring.This happened to some extent also when the epigenetically altered rats were fostered by other not stressed or violent rats.