A classroom is filled with college students taking an examination. They've all studied hard, they're all pretty good students -- with one or two exceptions -- and they all fail.

Do they feel as though they are stupid? Is their self-esteem damaged? Do they believe they'll never pass another examination? Probably not. Even the dimmest of them sees it as a problem with the test itself. Maybe it wasn't fair, but it wasn't anything they did.

In this class's next exam, though, everybody passes except one student. Now that could be trouble for that one student. Much more so than if he'd just been in the class where everybody flunked.

In certain individuals, that failure could spark a future of failures, poor self-esteem and giving up. This vulnerable individual might perceive any failure -- especially when he is the only one to fail -- as his failure. He is much more likely than any of his classmates who either flunked en masse or passed, to continue to do poorly, to give up, stop trying, eventually, perhaps, become medically depressed, and physically and mentally impaired.

This is a human reflection of the concept behavioral psychologists identifed two decades ago in animals, a phenomenon they call "learned helplessness."

In animals -- initially in dogs subjected to unavoidable electric shocks -- and subsequently in cats, rats, monkeys and other laboratory animals subjected to a variety of inescapable stresses, researchers noted common characteristics that appeared very similar to those seen in depressed humans. The animals appeared lethargic, demonstrated learning deficits, appetite disturbances, even mood disturbances. Tests also showed distinct immune system effects in the learned helplessness state.

But in animals who were given a way to escape from the stress, these conditions of learned helplessness did not appear. Indeed, when the animals who were given some degree of control over their environment were then subjected to the inescapable stress, they did not kick into the helpless, hopeless condition their litter mates experienced. But the stressed animals who had given up, continued to give up even when they were put into situations where they had the opportunity to escape.

People, the experts decided, are not so different from animals in their responses to uncontrollable stress -- although their responses can be modified depending on whether or not the stress is seen as uniquely their fault or something beyond their control.

Dr. Martin Seligman, at the University of Pennsylvania, who is credited with the earliest animal experiments demonstrating learned helplessness wrote subsequently about the application of the concept to people, and the necessity for taking into consideration, the uniquely human facility for perceiving implications of uncontrollable stress.

For example, he wrote, "You submit a paper to a journal and it is scathingly rejected by a consulting editor. Consider two possible attributions you might make: 'I am stupid' and 'the consulting editor is stupid.' If it is the first it implies a 'grimmer' future because no future paper is likely to be accepted. If the second, future papers have a better chance, assuming a different editor.

"In ordinary language, failure means more than merely the occurrence of a bad outcome. People say they have failed when they have tried unsuccessfully to reach a goal and attribute this to some internal factor. Obtaining poor grades in school is considered failure. But being caught in a flash flood is generally considered misfortune."

Essentially, said Dr. Alan Breier, research coordinator of the clinical section of the neurosciences branch of the National Institute of Mental Health, the behaviorists "bridged the work from the animals with a theory of depression that holds that the depressed person views the world as a series of events that are outside of their control." Since they feel powerless, he said, "they then do not put forth the effort and become somewhat helpless in their own situation and do not try to overcome the obstacles that they face."

Moreover, said Breier, "if you think that the inability to control the situation is because of a deficit you have, you are more likely to incur the depression and the other deficits of learned helplessness. Or if your world view is that 'it isn't my fault, it is some other reason,' the ill effects of failure may be avoided."

Breier and his colleages at NIMH have been applying some of the discoveries about the neurological and biochemical changes that can occur in psychiatric conditions in some tests using a learned helplessness situation for human volunteers.

Earlier studies have mostly been on volunteer college students, and have primarily looked at behavioral changes. Generally the students were given a learning test up to 45 minutes after their sessions of unpleasant stimuli. They were also asked to describe their feelings.

The studies show that people who are exposed to unavoidable adversive stimuli, like a loud noise or a shock, are more likely to perform poorly on the tests and report negative mood changes.

In the NIMH study, presented at a recent psychiatric conference and currently being prepared for publication, ten normal volunteers were subjected to a series of exposures to unpleasant stress.

The volunteers who could not escape it no matter what they did, showed higher levels of stress hormones in their blood and an increase in electrical activity on the skin. Studies showed that the biochemical changes correlated with the volunteers' reported feelings of tension, stress and unhappiness.

The studies are being expanded to include depressed patients as well as normal volunteers and also people who have had episodes of depression but have now recovered and have no symptoms.

"This," said Breier, "is a way of looking at whether there are some people who are particularly vulnerable to the effects of unavoidable stress, who, even in a non-depressed state, could show a pattern unlike that of normal volunteers or people who are not likely to develop depression.

"So we hope to, in essence, produce an emotional state in the laboratory like one of being stressed or unhapppy that may bear some resemblence to the stress and unhappiness of a form of a relatively mild clinical depression . . . then study it neurobiologically, based on the principles we've learned from animal studies."

A separate, although related study, is one Breier and his colleagues are just getting underway.

Based on work with primates in which baby monkeys were separated from their mothers and their peers and subsequently demonstrated clearly disturbed behaviors, the NIMH scientists are interested in studying adults who experienced a major separation from a parent during their childhood.

The studies are suggested both by a combination of soaring divorce rates and an inexplicable increase in the onset of depression in children and young adults at rates much higher than in the past.

"We know," said Breier, "that there is a relationship between separation and the development of anxiety and depression disorders. I think that early separation may be one of the most profoundly stressful life events, either through death of a family member or through divorce.

"Although not everyone who has had a separation has developed a psychiatric disorder, there is a significant percent who will. We hope to look at this group and try to tease out the neurobiological differences between those who are adversely affected and those who are not.

"When you think of all the children growing up in single parent homes, understanding these vulnerabilities could have widspread significance."

Adults who experienced separation from a parent during childhood may volunteer for NIMH studies, including a complete neuropsychiatric assessment. Phone Dr. Alan Breier, 496-6295.