Many preschool children go through a period of self-comforting habits such as hair-pulling, rocking or biting their nails. Children may run the gamut of habits, almost as if they were deliberately exploring behavior that bothers their parents.

Habits have deep roots. My first child sucked her middle two fingers as a newborn — an unusual pattern — and I found myself taking them out of her mouth.

My wife said, “You’d never recommend that to your patients. Why do you try to interfere?” I couldn’t answer her.

A week later, my mother came up from Texas to see her new grandchild. “Isn’t that amazing?” she said. “She sucks the same two fingers you used to! We couldn’t stop you.”

I realized then why I’d tried to stop my daughter. Attention to a habit is likelier to make a problem than break it. Thumb bandages, terrible-tasting ointments or other ingenious measures are counterproductive.

An older child can be helped to see that she turns to a self-comforting habit when she’s anxious and needs to calm down. Parents can evaluate the pressures that may prompt the habit: for example, over-scheduling; expectations that surpass a child’s developmental stage; or stresses that affect the whole family, such as a move or an illness.

Pressure doesn’t always come from the outside. A hard-driving child may need a habit to help her manage her own intensity.

One child, in the midst of a reprimand for nail-biting, pleaded, “Mommy, can you take my head off? My mouth just bites my fingers. I don’t like it and I don’t know what to do.”

The reaction shows the child’s depth of feeling as she tries to control the habit. Do we want to pressure her even more?

Instead you might say, “Most people bite their nails. Sooner or later you will stop. Meanwhile, worrying about it won’t help. I’ve made you feel guilty about it, and I’m sorry.” It’s better to reassure her that the habit will go away — which in turn is likelier to happen if everyone (including the child) can ignore it.

Various habits show a pattern. These guidelines may help:

1. Many 3- and 4-year-old children develop habits, often imitating a parent, sibling or peer. Habits last only a few weeks or months.

2. At a peak of frustration or excitement, a child resorts to the habit as she once might have used her thumb. A special doll or other treasured object to hold and touch might help redirect the child’s need to comfort herself.

3. A parental prohibition heightens the interest in the habit and tends to reinforce it. The habit as a form of rebellion makes it satisfying, too. The child’s habit is unconscious. So with attention what might have been transient becomes more fixed.

4. Much less often, involuntary behavior such as repetitive hand-washing or staring spells may seem to take on a life of their own.

If such habits have a bizarre quality or are disrupting the child’s life, they require attention. A mental health professional can determine whether treatment is needed (such as for obsessive compulsive disorder, Tourette’s syndrome or certain seizure disorders). Your pediatrician can refer you to a pediatric neurologist or child psychiatrist.

5. Criticizing the child for a habit makes her feel inadequate and unable to break it. A parent is best advised to ignore the behavior from the start. That’s not easy, because all parents are loaded with their own past experiences. A parent who was broken of a habit during his own childhood will find it extra hard to overlook such behavior now.

— New York Times Syndicate