Remember “The Princess and the Pea”? Maybe when you read that fairy tale about a young woman so sensitive to touch that she could feel a tiny pea through a stack of mattresses, it reminds you of some little one you know.

While your child may not be able to feel a lump under the bed, she may feel other seemingly little things with extraordinary sensitivity. What's going on when your child complains about the seam in her socks or the movement of loose clothing against her body or the brush of a kiss against her cheek?

Sounding the alert over a dangerous situation is one of the tactile system's most basic purposes. It's important for your child to be able to feel when a stove is hot or a knife is too sharp. These things are meant to elicit a big, attention-getting reaction.

As most children grow and develop, their nervous systems develop ways to inhibit that reaction when it's not really needed, but for children with sensory integration disorder, the tactile sense may remain on high alert. To your child, a scratchy tag may feel as painful as a knife, a pat on the head as dangerous as a blow.

Sensory Discrimination

Just as your child's nervous system may be unable to discriminate between what's safe and what's dangerous, it may be unable to discriminate between what's important and what's not important. Rather than filter out all the information that doesn't need to be dealt with consciously — the constant feel of clothes against the skin, furniture against the body, air brushing past the face — it all comes crashing in, leaving your child distracted and preoccupied by things you ignore. He may be unable to concentrate on things that would be helpful to feel, like the way shoelaces need to move together to tie a shoe or the way a button slides through a hole.

Your child may react to all this by avoiding new experiences and clinging to safe and comfortable ones that she has already found a way to process. She may seek to rigidly control all tactile input, finding that experiences she initiates herself are less threatening than ones that come to her, unpredictably, from others.

Out of Touch with Feelings

Some children whose tactile sense doesn't work right have the opposite of too much information — they don't seem to feel or respond to much of anything. Your child may feel light touch not at all, normal touch as a tickle, and only really register deep touch, hard hugs, and firm squeezes.

If your child can't feel when his face is dirty, his shoes are on backward, his diaper is wet, or his knee is scraped, he may be more underwhelmed by touch than overwhelmed by it. As with children who feel too much, though, his behavior will be directed by a search for sensory comfort. The better you can meet that need, the less he'll need to act up.