Traumatic brain injury, described as the signature wound of the Iraq war, may be less to blame for soldiers' symptoms than doctors once thought, contends a provocative military study that suggests post-traumatic stress and depression often play a role.

That would be good news because there are successful treatments for those conditions, said several nonmilitary doctors who praised the research.

Thousands of soldiers returning from Iraq have struggled with memory loss, irritability, trouble sleeping and other problems. Many have suffered mild blast-related concussions, but there is no easy way to separate which symptoms are due to physical damage and which are from mental problems caused by the traumatic stress of war. Imaging of the brain is being tested, but hasn't yet proven to be helpful.

People around the globe hit the height of their misery and depression in middle age, a new international study suggests.

The finding by British and American researchers was based on an analysis of well-being among approximately 2 million people in 80 nations. With few exceptions, the observation appears to apply across the board, regardless of gender, culture, geography, wealth, job history, education, and marriage or parental status.

"The scientific fact seems to be that happiness and positive mental health follow a giant 'U' shape through life," said study author Andrew J. Oswald, a professor of economics at Warwick University in Warwickshire, England. "For the average person, it's high when you're 20, and then it slowly falls and bottoms out in your 40s. But the good news is that your mental health picks up again, and eventually gets back to the high levels of our youth."

For many older adults, the "golden years" are indeed golden. My parents, who are both over the age of 65, are enjoying their retirement here in Northern California. My father is supervising the building of their new house and my mother runs a website she created for senior women. They go to baseball games and symphonies, among other activities, and spend a lot of time taking their grandchildren to museums of all kinds. I think they probably would be a good commercial for vitamins marketed to seniors.

Unfortunately, for some seniors, the golden years are more like leaden, especially if they're living with depression. Not only can depression suck all the enjoyment out of life, as it can at any age, but depression can also be dangerous to an older adult's physical health.

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