How Single Parents Affect the Brain - WSJ.com

Do children need both mothers and father? There's some suggestive research cited in the Wall Street Journal: How Single Parents Affect the Brain

Conventional wisdom holds that two parents are better than one. Scientists are now finding that growing up without a father actually changes the way your brain develops.

German biologist Anna Katharina Braun and others are conducting research on animals that are typically raised by two parents, in the hopes of better understanding the impact on humans of being raised by a single parent. Dr. Braun's work focuses on degus, small rodents related to guinea pigs and chinchillas, because mother and father degus naturally raise their babies together.

When deprived of their father, the degu pups exhibit both short- and long-term changes in nerve-cell growth in different regions of the brain. Dr. Braun, director of the Institute of Biology at Otto von Guericke University in Magdeburg, and her colleagues are also looking at how these physical changes affect offspring behavior.

Their preliminary analysis indicates that fatherless degu pups exhibit more aggressive and impulsive behavior than pups raised by two parents.
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Still, the prevalence of single-parent households has researchers looking at possible consequences for children. An OECD report found that just 57% of children in the U.S. live with both parents, among the lowest percentages of the world's richest nations.

The report, which sparked some controversy when it was released in September, found that children in single-parent households have an increased risk of delinquency and attention deficit hyperactivity disorder, or ADHD, as well as poorer scholastic performance.

The OECD also analyzed data from 122 separate studies and found that there was variability in the negative effects on children of living in a single-parent home; on average, the OECD found, the magnitude of the impact was relatively small. On a standardized intelligence test with a median score of 100 points, for example, a child in a single-parent family would be about 3.5 points worse off than a similar child in a two-parent family, according to Dr. Chapple, who co-wrote the report.