I am a mother of seven children, all married except the youngest, who is 20, in the 12th grade and about to graduate. She is slow, but we are proud of her for finishing high school as all of the others have.

Her behavior is the problem.

I wish I could talk to someone who has gone through or is going through this. I try to get help but they don't understand and psychiatrists cost too much and don't help.

My daughter has a phobia about clocks. It puts her in a trance when she sees a clock and then she talks vulgar and won't do anything you ask. She is not violent but is impossible to deal with.

She doesn't make friends and so is very attached to me, but I can't have her with me every minute. I am 59 years old. If I should die, who's going to understand her?

I am remarried. My husband helps with her but when this comes on no one likes it or knows how to deal with it.

This started in school when she was 15. The school told me to get help. She was sent to the adolescent center for a year and we had to go to family counseling three times a week.

But the phobia is still there. I want to help her get rid of this, for I feel it is hindering her from having a good life.

A number of doctors and other experts took a shot at your daughter's problem, came up with an assortment of possibilities and concluded that only two things were clear about her problem: It didn't fit any classic set of symptoms, and she needs a full neurological work-up to rule out possibilities, such as seizures.

These tests will include an electroencephalogram, probably with a portable 12- to 24-hour recording device. The doctor may have you show her a clock during that period to get a record of her reaction to the stress.

The Tourette syndrome also could cause the problem, although the symptoms began much later than usual. In this neurological movement disorder, the victim has physical and sometimes verbal tics, like vulgar language.

If this is her problem, she can control it by taking antipsychotic medicine, but it should be prescribed by a doctor who's used to treating the disorder, so she won't be given too much. Send a long, stamped, self-addressed envelope to the Tourette Syndrome Association, 42-40 Bell Blvd., Bayside, N.Y. 11361 for a state-by-state list of these doctors and for the Tourette support group in your area.

And then there's phobia -- an exaggerated, incapacitating fear -- that afflicts 13 million Americans. If your child is one of them, you'll be comforted to know that a single phobia is the easiest to cure, usually in 16-20 weeks. Most doctors say this diagnosis is unlikely (real phobics don't lose control), but it's worth checking because your daughter does go into a trance. This sometimes is experienced by a person in the middle of a panic attack -- and a panic attack is the source of any phobia.

Such an attack -- a frightening, irrational, unexpected bout of anxiety -- can cause the victim to feel like she's having a heart attack or going crazy or losing control. This may make her so afraid of another attack that she gets scared of whatever she was looking at or riding in or doing when the attack began to build: A phobia is born.

Doctors believe that panic attacks, actually have a biological cause because they run in families; they happen to women twice as often as men (generally in the early childbearing years and shortly before menstruation) and they may be brought on by such substances as lactate -- produced in the body by exercise -- and caffeine.

You can test caffeine by taking your daughter off coffee, tea, colas, chocolate or any medicine that contains caffeine and off sugar too, which makes some people anxious. For phobia information, get the free booklet, Useful Tips About Phobias and Panic, by the National Institute of Mental Health, from the Consumer Information Center, Dept. 580-R, Pueblo, Colo. 81009; read The Anxiety Disease, by David V. Sheehan, (Scribner's $15.95), and send a long, self-addressed envelope with a 39-cent stamp, to the Phobic Society of America, 133 Rollins Ave., Suite 4B, Rockville, Md., 20852-4004, for information about phobias, support groups and centers around the country.

If none of this applies, your daughter may need a check-up with a doctor who believes in cerebral allergies, because some say they've cured patients of Tourette-like symptoms and of phobias by changing their diets or their environments.

Once you identify the problem, you can get the right treatment for your daughter, but the problem may disappear when school ends. A clock to a slow student could be like a calendar to a prisoner -- a constant reminder of time still to be served.

Whatever the cause, give her as much love, affection and acceptance as you can afford and let the future take care of itself. Questions may be sent to P.O. Box 15310, Washington, D.C. 20003. Worth Noting

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