The assumption that depression is a disease has been supported by biologists, psychiatrists and companies producing medicine. Although advances in medical treatment have certainly been responsible for reducing much suffering, sticking to the disease model is preventing a more complete understanding of why we are so likely to suffer from depression, with at least 45% of people experiencing the condition in their lifetimes.

My recent review of theories and personal observations suggests that depression might serve some useful functions. We should not forget that depression has meaning, and that there is a real new life after recovery.

A recent study of depression in Holland showed that people seemed to cope better with hardships in life after depression than they were doing before it. In the group as a whole, liveliness, psychological health, social and spare-time activities, performance at work and general health all significantly improved upon recovery from depression.

Depression can lead to great insights(洞察力) and achievements. More than 2,000 years ago, Aristotle believed depression to be a state of great moral and spiritual value because of the insights it could bring. The philosopher John Stuart Mill wrote his famous work, Utilitarianism, at the age of 19 and became depressed at the age of 21. Upon recovery, he admitted that the experience had taught him an important lesson---that he should not sacrifice(牺牲) his social and emotional development to intellectual ambition.

Theories have suggested that depression could be a defense against the long-time stress. It is possible that depression defends us against the tendency to ignore our true needs by chasing unobtainable goals and helps to bring these needs into sharper focus.

Depression may bring about a “rebirth” because it removes a false idea about oneself. There is some evidence from scientific studies to show that depressed people are rather more realistic in their thinking than “healthy” individuals. With recovery, a new kind of truth could be found, which would do away with blind optimism: a more modest evaluation of the depressed person’s own ability, containing a more balanced picture of his or her life.

Depression may have forced our ancestors to look again at their strengths and weaknesses, and their coping strategies. Regardless of the reason for falling into depression, the journey has potential to make us better equipped, in a general sense, for life.

Mental illness and disability were family problems for English people living between 1660 and 1800. Most women and men who suffered from mental illness were not institutionalized as this was the period before the extensive building of mental hospitals. Instead, they were housed at home, and cared for by other family members.

Now a new study by Cambridge historian Dr. Elizabeth Foyster will reveal the impact on families of caring for mentally ill and disabled relatives.

Much has been written about the insane themselves but few studies have considered mental illness from the perspective of the carers. The lifetime burden of caring for those individuals whose mental development did not progress beyond childhood, and who contemporaries labeled as ‘idiots’ or ‘fools’, has been little explored by historians. Foyster’s research, which has been funded by the Leverhulme Trust, will carefully examine the emotional and economic consequences for families at a time when the Poor Law bound them to look after their mentally ill and disabled family members.

By asking key questions about the impact of ‘care in the community’ in the 18th century, Foyster hopes that her research will bridge social and medical history. Specifically, she aims to provide an historical perspective for contemporary debates such as how resources can be stretched to provide for children with learning difficulties and an aging population.

“The stresses and strains of family were worsened by high infant mortality and low life expectancy, and many individuals were pushed towards mental breakdown,” she explained. “Moreover, inherited conditions, senility(高龄) and what today would be described as ‘special needs’ could put great emotional demands on family members who had primary responsibility for their sick or disabled relatives.”

The research will shed light upon how caring for the mentally ill and disabled raised difficult issues for families about the limits of intergenerational responsibility, and whether family ties were weakened or strengthened by the experience. The questions of how far shame was attached to having insanity or idiocy within a family, and at what point families began to seek outside help, will also be addressed.

“The family must have seemed an inescapable feature of daily life between 1660 and 1800,” said Foyster. “Although there were those who were abandoned and rejected, for the majority, mental disability was accommodated within the family unit. I aim to get to the heart of what this really meant for people’s lives.”

As people age, the body changes in all sorts of predictable ways. Brains can slow. Wounds take longer to recover. And sleep patterns(模式) shift, too. This can come as news to many, says Michael V. Vitiello, a psychologist at the University of Washington who is expert in sleep in aging.

The most noticeable---and often most annoying---changes are how sleep and wake-up times change and sleep gets lighter, often beginning in middle age. Gone are weekend sleep to 11 a.m. and the ability to sleep through a noisy garbage truck down the block.

But not every restless night can be ignored. Studies have found that poor sleep can create a particular threat to older adults---Falls, depression and anxiety, problems with memory, and increased suicide(自杀) risk are among the effects of sleep issues in this population group that researchers have found. But scientists are still unsure why those risk connections exist.

What is clear is the connection between good sleep and psychological well-being in older adults. A 2010 study showed us that connection when it came to sleep quality, but sleep quantity didn't show the same effects. And that, experts say, may be the key to understanding sleep as you age. If you're sleeping less, but don't feel negative effects out of bed, the changes you notice may just be normal age-related.

Over time, Vitiello says, sleep patterns simply change. "A lot of older adults recognize that they don't sleep the same as they did when they were 18, but they can still function and they're OK. And all is well with the universe."