SOMETIMES I'LL ask a couple I'm seeing in therapy to do the following exercise.

1. The husband and wife stand about six feet apart.

2. The husband walks slowly toward his wife until he reaches a point where he no longer feels comfortable. Some men stop about three feet from their wives. Others stop at 30 inches and still others at 27.

3. The wife now moves toward her husband or steps back from him, depending on how much space she feels she needs between the two of them.

The purpose of the exercise is to help a couple understand that each has an invisible boundary line. If the husband moves into the wife's space, shell immediately step back to reestablish her boundary. Everyone has a different physical comfort level.

It's a fascinating phenomenon to observe in yourself as well as others. Walk up to anyone and generally you'll see the person step back from you or move toward you. If the person steps back, you may move closer. If the person steps forward, you may move back. Usually the two of you will move around until you establish a comfortable space between you.

Just as people have invisible physical boundaries, they also have unspoken psychological ones. When these are crossed, there is discomfort and sometimes even an argument.

One psychological boundary people have is their tolerance for talking. Some people like to talk. Others like quiet.

If a wife likes to talk and her husband likes quiet, her talking may create a sense of uneasiness in him. His psychological space is being invaded. He may address his discomfort by walking out of the room or tuning out. The wife, on the other hand, may feel anxious when her mate doesn't talk. One might say her psychological space has been invaded by his silence. She may address her uneasiness by picking a fight to get the verbal energy flowing.

Household noises often cross people's psychological boundaries. One spouse may like the TV volume higher than the other. When the volume is up, one person feels intruded upon, but when it's down, the other is uncomfortable. One couple has trouble when the husband watches sporting events, particularly football. His wife becomes anxious and distressed. The continual talking of the announcer and the roar of the crowd impinge so much on her psychological boundary that she feels a need to run away and leave the house.

Another psychological boundary involves how much information spouses believe they should share with others about their relationship. The husband may see no problem with telling his best friend that they're having financial difficulties. But the wife may think that discussing their problems with others is a betrayal of the relationship.

A couple may have different psychological boundaries when it comes to the number of things they like to have around the house. Some people feel most comfortable with many collectibles sitting around. Others want absolutely clean surfaces and a lot of knickknacks create a sense of discomfort. Think of yourself and your mate. How far apart are your psychological boundaries for talking? Noise level? Sharing information with others? Items around the house?

Conflict frequently results when couples fail to respect each other's psychological boundaries. Understanding your boundaries as well as your mate's will make you more tolerant and reduce stress between the two of you.

Doris Wild Helmering, LCSW, is a psychotherapist in private practice in St. Louis. She is the author of eight books, numerous magazine and newspaper aticles and is a frequent guest on TV and radio. Doris has guided countless individuals and couples to more satisfying relationships with her practical, solution based action plans. Visit Doris at http://www.doriswildhelmering.com/blog