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Epigenetics,
research about learned behaviour being inherited by the way genes are expressed, e.g. being switched on or off.

From the homepage of the Swedish Radio : (Quick & dirty translation)
Mouse kids are different, according to their mother's childhood.
A stimulating childhood not only influences the brain positively during adolescence. Influences of such stimulus are also inherited by the next generation, at least with mice, as reported by American scientists in the Neuroscience magazine.
Mice inherit their mother's good childhood.

( The study is about mice with a genetically induced defect in memory, some of which had a very stimulated upbringing which increased their memory capacity. The next generation, regardless of if they had been given to foster mothers, showed an improved memory capacity if their biological mothers had had a stimulated childhood.)

Per Jensen, professor in epigenetics at the university of Linköping, Sweden : (translated)
" Earlier studies, also in Sweden, mostly about the disposition towards illness, have shown similar epigenetic patterns of inheritance with humans. ---"

Source:
The Journal of Neuroscience. 2009 4/2 1496-1502. ”Transgenerational Rescue of a Genetic Defect in Long-Term Potentiation and Memory Formation by Juvenile Enrichment.” doi: 10.1523/JNEUROSCI.5057-08.2009