"I should have been a bear," the young woman told her psychiatrist.

She said it with some ironic humor, but wistfully. And she has begun to learn that she spoke more accurately than even she had realized.

"Bears," she said, "are allowed to hibernate, and people aren't."

Ingrid Bush (not her real name) is from the New York area. Her perceptive observations about her own cyclic depressions -- and her response to some preliminary treatments -- is helping to open a new field of research into the relationship of changing seasons to chronic mood disorders, especially those the experts call bipolar depressions: the cycles of manic highs and debilitating lows.

For most of her adult life, Ingrid Bush has suffered from a manic-depressive disorder which finds her almost dysfunctional in the winter, with both her mood and her energy levels at low levels, and just the opposite in the summer when she is "hypomanic," a term describing an abnormally high mood that is somewhat less severe than true mania.

For the past dozen years or so, Ingrid Bush has moved about, spending a few years in her native New York, but also spending considerable time in Quebec and some months in Atlanta.

Bright and perceptive and eager to overcome, her mood disorder, she noted and reported to her New York therapist these observations:

The further south she lived, the later in the year the depression would have its onset, the shorter it would last and the milder its peak.

The further north she lived, the earlier the depression came on and the longer it lasted.

During the summers she spent in the North, she did not become hypomanic, but remained in a normal mood state.

In New York, her summers were filled with hypomania and its characteristics: excessive energy, sleep difficulties and judgment problems.

Ingrid Bush is one of several patients brought to the attention of a group of psychiatrists at the National Institutes of Health who are on the leading edge of research into how the human brain works. Much of the knowledge on which they are basing their work derives from discoveries about the brain's biochemistry and biochemical responses to external factors made within the past decade.Much of their work is in hitherto uncharted areas, aimed at disentangling a series of psychobiological feedback systems and instantaneous operations, so complex Houston Mission Control pales by comparison.

In particular, the HIH scientists so intrigued by Ingrid Bush are studying the biological rhythms which seem to play an integral role in the way the human animal -- body and mind -- functions, indeed, the way all life on earth may function to one extent or another.

"Make no mistake," says Dr. Frederick Goodwin, chief of the clinical psychobiology branch of the National Institute of Mental Health, "these are not what you hear about as "biorhythms,'" the astrological pop fad that purports to predict good days and bad according to one's birthday. "You can put aside the biorythm craze," says Goodwin, "except as a measure of how interested people would be in a really scientific way to measure rhythms. . . "

The chronobiology-psychiatrists at NIH do use an activity monitor, a wrist device which can measure long-term cycles in patients as they go about their usual lives. "There are long-term biological rhythms," says Goodwin, "and they may turn out to be of some predictive value."

Dr. Norman Rosenthal, an associate of Goodwin's, is particularly interested in the seasonal relationship to cyclic mood disorders like that of Ingrid Bush. He is speculating, again on the basis of a number of recent studies, that their relationship to the seasons may be a function of their relationship to the length of the day, to the relative proportion of daylight to darkness.

There is new evidence, the scientists note, that "light itself has important effects on brain function." A hormone produced by the pineal gland, for example, is suppressed by light.

The work at NIMH on measureable biological (or circadian) rhythms, sleep disorders and activity-monitoring has led to clinical observations, says Goodwin, "that patients who have manic-depressive illness tend to have biological rhythms which are poorly regulated . . . they were behaving as if they had some problem in processing information such as time cues," or cues from the environment such as light.

"What we are saying," says Goodwin, is that "depressed patients may process light differently."

And very carefully, very cautiously, Goodwin and Rosenthal say that they "have some evidence that exposure to bright light, that is, artificially lengthening their winter day into a summer-length day may reverse this depressive process . . ."

The results, they emphasize, are very preliminary. But Rosenthal, especially, can barely conceal his excitement over the possibility of an innovative, light-altering treatment and the sense that he is on the verge of a major breakthrough in the treatment of a devastating disorder that often strikes the most attractive and creative people.

Back to Ingrid Bush.

"Last year," says Rosenthal, "her light pattern was artifically changed and she managed to get through the winter for the first time without having a crippling, hibernation-like state."

A similar improvement was found with another patient, a scientist himself, who kept careful records of his high and low cycles for almost 15 years.

"In the fall of last year," says Rosenthal, "we exposed him to a certain kind of light regimen and switched him out of his depression after about three days. . . . He's now been out of his depression for about 26 weeks, which is the longest in his adult life he's ever been non-depressed."

What the psychiatrists would like now is to set up a group of volunteers -- patients with depression cycles seemingly related to seasonal changes -- to participate in a treatment program (free, of course) to determine if these cycles can be reversed, perhaps ended, by manipulation of light.

The psychiatrists stress that they are speaking of people who suffer severe symptoms, not the poetic melancholy of spring and fall (when, they note, the relative relationships of light and dark are changing most rapidly).

They are looking for people, says Rosenthal, "who have gone through enough cycles to know that this is going to happen again. Because as (Ingrid Bush) said to me, when the torpor and the depression cleared up, she would think of herself, 'aha, it's gone,' and then forget completely about it. She says she was like the grasshopper who played through the summer, forgetting that the winter had ever been, until the fall came and then she would recognize that here it comes again. . ."

Although he is particularly interested in winter lows alternating with summer highs, Rosenthal would like to hear from anyone with distinctly seasonal mood disorders. Applicants will be sent questionnaires, from which participants will be selected.