For couples whose relationship has become "lifeless and mechanical," psychologist Nathaniel Branden suggests this "homework assignment" -- predicated on 12 hours alone together.

"No books, no television, no telephone calls." But a couple may sit silent for several hours.

At first, says Branden, there is self-consciousness. "There may be joking or sparks or irritation. But almost always, after awhile, communication begins."

One partner may talk about something that makes them angry. They may quarrel.

But soon, claims Branden, "There is a growing closeness, a new intimacy. Very often they make love."

At this point, a couple often thinks the exercise has worked and they might as well call it quits.

But if they stick with it, "They soon move down to a much deeper level of contract and intimacy . . . Often they share feelings they have never discussed before."

There is "almost always a gradual deepening feeling, a deepening emotional evolvement, an expanding experience of aliveness."

Generally, says Branden, "the day ends happily. But sometimes it ends with the realization that the relationship may no longer serve the needs of either and that they may not wish to remain together."

For a couple who loves each other -- but do not know how to communicate or make the relationship work -- Branden maintains this exercise, practiced once a month, "can produce the most radical changes."

A relationship "needs time," he says. "It needs leisure."