When you're touched, the nerve endings under your top layer of skin, or epidermis, send electrical signals to the brain. When we are tickled the somatosensory cortex picks up the signals to do with pressure, but the anterior cingulated cortex also analyses the signals.

What causes a person to be ticklish?

One theory is that being ticklish evolved as a defense mechanism to protect vulnerable areas of the body and to show submission. ... In fact, the body movements of someone being tickled often mimic those of someone in severe pain. Older research shows both pain and touch nerve receptors are triggered during tickling.

Is tickling good or bad?

Tickling has long since been used as a way of torture. ... Many of the study subjects reported tickling as a type of physical abuse. The study concluded that tickling can provoke extreme physiological reactions in the victim such as vomiting and loss of consciousness due to the inability to breathe.