Michelangelo probably had osteoarthritis, but his commitment to art may have kept his hands functional until his death in 1564. Those are the conclusions drawn by doctors who studied three portraits of Michelangelo from ages 60 to 65 by other artists.

The paintings show that the small joints of his left hand were affected by noninflammatory degenerative changes, yet earlier portrayals show no such deformity.

"Continuous and intense work could have helped Michelangelo to keep the use of his hands for as long as possible," said Davide Lazzeri, a specialist in plastic reconstructive and aesthetic surgery at the Villa Salaria Clinic in Rome and an author of a report in the Journal of the Royal Society of Medicine.

Sleeplessness and false confessions

Sleep deprivation may lead individuals to confess to crimes they did not commit, research suggests.

In the study, which appears in Proceedings of the National Academy of Sciences, researchers asked 88 undergraduate students to complete computer tasks in two sessions separated by a week. The students repeatedly received warnings that pressing the escape key would erase the researchers' data.

The night after the second session, half of the participants slept in the laboratory and the others were kept awake with food, television and video games.In the morning, the subjects were asked to sign a statement falsely alleging that they pressed the escape key. Half of the sleep-deprived individuals signed it, compared with 18 percent of the rested subjects.

"It's true, this is a far cry from confession to a murder. But we do know we can also get people to confess to things with more serious consequences," said Elizabeth Loftus, a cognitive psychologist at the University of California-Irvine.

As many as 17 percent of interrogations occur during normal sleep hours, midnight to 8 a.m., the study notes.

Wildlife hurt by noise underwater

They may seem innocuous, but the noises our machines make underwater may be hurting wildlife, two studies said.

The first study found that ship noises could hurt endangered killer whales. But a second, published in Nature Communications, finds that noise pollution may have a far more severe effect on smaller fish: It can be fatal.

The effect such noises have matters; the British, Canadian and Australian researchers point out that the world's coastal regions are "experiencing unprecedented human population growth." "The combination of stress and poor responses to strikes by predators is why these fish became such easy prey," Andy Radford of the University of Bristol said.

The team of researchers, led by Stephen Simpson of the University of Exeter, said it appeared the noise make the fish breathe more heavily so that they consumed more oxygen and it slowed their ability to respond to a dangerous situation, increasing a predator's success at capturing the fish.

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