Stories by Richard J. Wurtman

Several related behavioral disorders recognized in the past decade are characterized by disturbances of appetite and mood. One of the best-known is seasonal affective disorder, or SAD

It brings dementia and slow death to more than 100,000 Americans a year. No one knows its cause or how to stay its inexorable course. Investigators are focusing on six conceptual models of the disease

They are the precursors of neurotransmitter molecules. Increasing their level in the brain amplifies signals from some nerve cells. In effect they act like drugs, and one day they may serve as drugs

Sunlight tans skin, stimulates the formation of vitamin D and sets biological rhythms. Light is also used in the treatment of disease. Such effects now raise questions about the role of artificial light

When a meal rich in carbohydrate is eaten, the brain makes more of the nerve impulse transmitter serotonin. The mechanism may be part of a closed circle in which diet influences food consumption

The function of this small organ near the center of the mammalian brain has long been a mystery. Recent studies indicate that it is a "biological clock" that regulates the activity of the sex glands