Five-year-old Mary is sitting at the table colouring with her crayons while her mother is studying for her university course. Mary begins to tap the crayon against the table. "Please stop that, Mary," her mother says crossly.

Mary stops, but soon starts again: "Mary, cut that noise out - I won't ask you again." Mary stops but soon resumes.

Her mother slams down her book, reaches over and slaps the child, screaming: "I said stop that! Why do you keep doing it when you know it annoys me? Why can't you sit still and be quiet?"

It is clear that mother is not having success in getting her need for quiet met; on the contrary, matters are escalating.

The reason for this is that she is reacting to the child's irritating behaviour rather than attempting to understand it. To understand is a process of getting beneath the behavioural stance of self or another - in this case the child's tapping-the- crayon behaviour.

Every behaviour has an intention; just as her mother's request for Mary to stop the noise has the intention of securing quiet so that she can study, so Mary's tapping behaviour also has motivation. Some writers believe that the child does not know, in spite of her mother's anger, why she is persisting with the annoying behaviour.

However, I believe the child does know, but dares not express directly her hidden need for fear of rejection. Ingeniously, she finds an indirect way of expressing her hidden goal.

Neither mother nor daughter is clearly expressing her needs; indeed both are exhibiting distressing behaviours. It would help enormously if mother sought to understand her own irritable response and expressed her need clearly: "Mary, I need you to be quiet so that I can concentrate on my study and finish it so that we can then have some time together."

It is ironic that mother, in her exasperation, asks the child: "Why do you keep doing it?"

The child could equally ask: "Why do you keep getting cross with me?" Communication is not at all clear between them.

It is important that mother sees she is the main architect of the relationship that exists between her and the child. Children so depend on their parents for love, nurturance, education and social and spiritual development. When there are any threats to these vital needs children find creative ways to reduce the threats.

If mother wants Mary to co-operate with her need for quiet to study, she needs to express it clearly and also attempt to understand the child's difficult behaviour. Only when the child's hidden need is identified, acknowledged and a commitment to meeting that need is made (where possible) will a change occur.

Sometimes the hidden purpose of a child's behaviour can be discovered by examining the results. Sometimes direct questioning may be too threatening, particularly when there has been a history of needs not being heeded.

In looking at the results in the above interaction, the mother became annoyed. Mary wanted to annoy her for a hidden reason, and when her mother slapped her Mary secured her mother's full attention.

Why would she stop? Look at the magnificent results! She can keep her mother occupied with her and no longer endure the emotional threat of being ignored.

Mary's tapping says: "Look at me! Talk to me instead of burying your nose in your books!" If her mother tapped into the child's need and if the child's quiet moments of constructive play brought a warm smile from her, a warm hug and a word of praise, the child would be far less inclined to get her attention through disturbing behaviour.

Disturbing behaviour is a clever projection from the child's mind and heart of an inner disturbance.

By responding to the inner disturbance, the mother will be effective in reducing its manifestation.

However, she needs also to be in touch with her own inner annoyance and do her best to respond to both the child's and her own needs.

Children not only need to be loved but they also need to love. Giving children the opportunities to be helpful, supportive and involved in the meeting of their parents' needs is essential to effective parenting.

Mother requesting Mary's support for her study, and overtly appreciating the child's efforts to respond to the expressed need, would possibly have not lead to the unpleasant scene between them.

Dr Tony Humphreys is a consultant clinical psychologist and author of A Different Kind of Discipline