Having Children Makes You Wiser

"Elizabeth Gould of Princeton University and her colleagues compared the brains of marmoset fathers with those of males that lived in mated pairs, but lacked offspring. They found substantial differences. The nerve cells in the prefrontal cortex of fathers had more tiny projections, known as dendritic spines, than those of non-fathers. Because dendritic spines are the sites of connection between neighbouring nerve cells, the increased number may mean more activity in the fathers' brains than in those of the non-fathers. The nerve cells in the prefrontal cortex of the fathers also contained more receptors for vasopressin, a small peptide that influences social behaviour and pair-bonding.

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Craig Kinsley of the University of Richmond, Virginia, who did the work with rat mothers, speculates that Dr Gould's new findings may reflect human behaviour quite closely. “There is a lot of interest in the idea that having children forces responsibility on males in many respects. If you consider that the prefrontal cortex plays a major role in planning, judgment and the anticipation of the consequences of behaviour, you could make a clear argument that the changes in that part of the brain would be involved with judicious attention toward offspring.”"

http://economist.com/science/displaystory.cfm?story_id=E1_SRNSDQS