Baby Gives Mom New Neurons
Researchers exposed virgin female rats to foster pups every day until they began to exhibit maternal behavior, like crouching over the pups, grouping them and retrieving them back to the nest. The data showed that the rats exposed to the pups have increased numbers of new neurons.
Other studies in mice, hamsters, monkeys and even humans have found similar results. An increase in the creation of new neurons occur during pregnancy and lactation and now for the first time have been found to also be the case in rats that have not been pregnant or nursing. Maternal behavior in itself was enough to activate the increase in neurons.
One explanation is that the hormone prolactin may play a role, in that the prolactin stimulates both the onset of maternal behavior as well as new neurons. The other explanation is that the stimulation from the young themselves plays a crucial role in increasing neurons in the maternal rats.
http://www.sciencedaily.com/releases/2009/12/091217115832.htm
