They'll blink, as if unaccustomed to light and air. They'll seem preoccupied, wary and distant. Some will act confused and be reluctant to talk, while others will have a compulsive need to talk. But the talk will be chatter, as idle as it is compulsive. There will be almost no talk about the ordeal they have been through.

Generally speaking, that is how psychiatrists say the Americans held hostage in Iran will behave in the days immediately ahead.

While they disagree on the depth of post-captivity trauma, psychiatrists agree on one thing: all the hostages have suffered enough to be struggling with their emotions in the weeks ahead.

"They are survivors of an ordeal," said Dr. Robert Jay Lifton, professor of psychiatry at Yale University, "and survivors have conflicts and suffer the psychological effects of what it was they survived. They will carry indelible images of what they've been through."

The ordeal they have been through should not be minimized. The men and women held hostage by the Iranians were kept apart most of the time -- mostly on separate floors, in separate rooms and even in separate locations. One of the two women spent at least 10 days in solitary confinement. Some of the men lived for days in tiny cubicles.

Often, they had to ask to use the Bathroom. Frequently, their conversation was restricted to their Iranian captors, who at times wore masks to conceal their expressions. The hostages were kept in the dark a lot. Their sleep was kept short. They were forced to sleep with their hands loosely tied. Their shoes were taken away. They had little mail since August and almost none since the outbreak of the Iran-Iraq war. There have been reports they were moved at least twice since the aborted U.S. rescue mission last April.

The hostage were lectured often on Marxist ideology by members of the People's Struggle Party and on the Islamic Revolution by their more conservative captors. At least two of the Iranian "students" who held the hostages were believed to be professional brainwashers enlisted by the People's Struggle Party for this purpose.

Harvard University's Dr. John Clark, a psychiartrist who has studied cult, hostage and prisoner-of-war psychology, has pointed out that, by isolating the hostages, by keeping them in the dark and depriving them of sleep, the Iranians followed a practice perfected by the North Vietnamese on American prisoners of war.

"These processes don't lead to the kind of overwhelming terror that might protect the mind," Clark said. "They lead to a narrowing of attention that brings on a trance state, where everything seems ambiguous. Ambiguity is at the bottom of all this. Suddenly, it becomes impossible for the central nervous system to handle it."

During their captivity, some hostages were quoted publicly as saying they had been treated well, that their captors were not all that bad. They had nasty things to say about the late shah: Why shouldn't he have faced trial in Iran, after all the crimes he committed against the Iranian people?

Psychiatrists suggested that these statements were signs that the hostages had undergone subtle but systematic brainwashing.

What have the hotages gone through? Psychiatrists say that at one time or other all of them may have been stricken with such overwhelming anxiety and a fear of the unkown that they began to fear for their lives.

"The fear of death has a bizarre aspect and often comes with obsessional thoughts like, 'Oh, my God, I didn't pay the insurance bill,'" said Dr. Steven Pieczenik, a Washington psychiatrist who is an expert on hostage psychology. "It's a way of displacing our anxieties, but it's also telling us, 'Hey, we're in trouble.'"

The "trouble" phase quickly passes into a regression phase, which is psychiatric jargon for saying that the hostages suddenly realize they are dependent on their captors for everything, like children depend on their parents. This establishes an alliance between captive and captor where the captive loses his personality.

On losing his own identity, the captive turns to his captor, an act of reidentification that psychiatrists refer to as the Stockholm Syndrome. This takes its name from an incident in 1976 when a woman held hostage in a Stockholm bank vault had sex with her captor. They later married.

The Stockholm Syndrome may account for some hostages saying their treatment has not been all that bad and that their captors were really pretty decent people. One State Department psychiatrist said, "We've had hostages who've been beaten and tortured, and they've come out and shaken hands with their captors. It's all very puzzling."

The hostages in Iran may have suffered deeper harm to their personalities, in part because of the way they were held captive. Their Iranian captors often put masks over their faces, kept them in the dark and isolated them from the other hostages. At times, the only noise they heard came from crowds screaming slogans on cue outside the embassy compound's walls.

Psychiatrists say that all these acts may have served to deepen the anxiety the hostages must have felt. How deep? It is possible that some of the hostages suffered hallucinations, even psychosomatic pain and illness. There is no way of telling until they are questioned and examined by psychiatrists.

Yale's Dr. Robert Jay Lifton said, "Some of them will need no treatment at all, but others may need at least some form of counseling or discussion. One should not assume that all the hostages will be disturbed. They will vary on how they've handled their experience."

The hostages are a mixed bag of people. Half are single, half are married.

Almost half are military. Nine were Marines assigned to guard duty at the embassy when taken hostage. The Americans range in age from their 20s to their 60s.

Psychiatrists say there is no way to predict which of the hostages will suffer the most from their ordeal. The youngest are the most flexible, and the most vulnerable.

The older hostages may have learned to repress their emotions, but on being freed may have a far more difficult time readjusting.

The nine Marine guards could have the most trouble, in part because they might find it harder to forgive themselves for being taken hostage in the first place.Says one psychiatrist: "It's not kosher for Marines to be taken captive, for any reason at all."

Their youth could make it even more difficult for the Marine guards to readjust to freedom. Said Harvard's Clark: "The younger ones won't handle it as well. Their generation is not as well furnished in identification; they've grown up in a more flexible and uncertain culture. Some of the older hostages will have had firmer memories, more elaborate defenses against their captivity."

Will the married hostages lose the scars of their captivity more quickly than the single ones do? Not necessarily. They may return to find that their spouses and children don't understand the depth of their suffering.

They may return to find that their spouses learned to make decisions they did not have to make before and that they like the new responsibility. The hostage might resent it, believing he wasn't missed. The wife may not want to resume her former role. There may be what one psychiartrist calls a period of "conflict and misunderstanding."

Psychiatrists say the best treatment the hostages can get is a kind of benevolent neglect. Too much comfort, too many questions, too much counsel may be just what they don't need.

"They ought to be allowed an interim where nothing is expected of them," one psychiatrist said. "They should be allowed to emerge from all this on their own, at their own speed." Said Yale's Lifton: "Some of these people will feel guilt, anger and confusion for a long time. They may be struggling with this for weeks and even months to come."