Sensory processing disorder is a condition in which the brain has difficulty in receiving and responding to information that comes in through the senses. In fact, it refers to the way the nervous system receives messages from the senses and then turns them into proper motor and behavioural responses. Generally, all the activities such as reading a book or riding a bicycle requires accurate processing of sensation. It is some sort of neurological traffic jam that prevents certain parts of the brain from receiving the information required to interpret sensory information accurately.
Sensory processing disorder may affect a sense such as touch, sight, taste or movement. It may also affect multiple senses. In this disorder, the person may scream when touched or may vomit or dive under the table after hearing the sound of a leaf blower outside the window. In some cases, the person with SPD may remain unresponsive to anything around him. Even he may fail to give any response to extreme heat or cold or pain.