Dr. William H. Frey II has established biochemical mechanisms for human emotional crying, but he and others have confirmed that cultural imperatives play their part, too.

As part of his ongoing tear work, Frey did one of the largest studies ever conducted on crying, his sample being composed mostly of white residents of Minnesota ranging in age from 18 to 75. Most of the detailed results were published in Frey's 1985 book, "Crying: The Mystery of Tears" (Winston Press, Minneapolis).

Frey and his researchers examined the cause, frequency and timing of some 1,500 crying episodes from 286 females and 45 males who kept meticulous crying journals for a month, and from another 200 women and 124 men who kept less complete records.

Among their results:

Interpersonal relations and "media" -- comprising TV, movies, plays, books and news reports -- were cited as the main causes of emotional tears, making up more than 70 percent of the reasons for crying. (But the emotion behind 21 percent of female tears was cited as "happiness," including brides walking down the aisle, an almost universal finding.)

Frey's researchers also found that crying reduced the intensity of feelings of sadness or anger by a factor of about 40 percent.

"So," he said, "as a way of alleviating stress, my advice is that when people feel like crying, they should allow themselves to do so. In any case, they should not try to prevent this natural process from occurring." --