At middle age, a great ape will neither cheat on a spouse nor buy a red sports car on impulse. But researchers have found that chimpanzees and orangutans experience midlife crises just as humans do.

That finding, published in the Proceedings of the National Academy of Sciences, could upend beliefs about the roots of human happiness. If our animal relatives share our propensity for sadness at life's midpoint, perhaps the crisis that humans feel near the 50-year mark is driven by biological factors -- not the wearing responsibilities of jobs and family and the dawning recognition of our mortality.

"This opens a whole new box in the effort to explain" the midlife dip in well-being, said senior author Andrew Oswald, a behavioral economist at the University of Warwick in England. The study involved primatologists from Scotland, Japan and Arizona who devised a census of 336 chimpanzees and 172 orangutans. When the composite well-being score for each ape was plotted according to age, the result was the same pattern seen in humans. Around ages 28 and 35 -- roughly the midpoint of life for chimpanzees and orangutans -- moods sagged and they became less socially engaged.


Can the wrong type of toilet training lead to incontinence? Probably not, a study says.

Broadly speaking, parents use one of two techniques. The first, sometimes called parent-oriented, rewards good behavior and punishes accidents by withholding the reward. In the other, called child-oriented, parents wait until the child seems ready for training, usually around 18 months or older, and then praise success and ignore accidents. The American Academy of Pediatrics suggests the child-oriented approach, but until now there has been little research to support either.

A study, published online in Clinical Pediatrics and led by Dr. Joseph Barone, a professor of urology at Robert Wood Johnson Medical School in New Brunswick, N.J., found no association between urge incontinence and the toilet-training method.


A large study suggests that people with serious attention deficit hyperactivity disorder are less likely to commit crimes when taking medication.

The study, published in the New England Journal of Medicine, examined records of 25,000 people in Sweden to see if those with ADHD had fewer criminal convictions when taking medication than when they were not. Of 8,000 people whose medication use fluctuated over a three-year period, men were 32 percent less likely and women were 41 percent less likely to have criminal convictions while on medication. Patients were primarily young adults. Medication varied, but many took stimulants like Ritalin.