Pain is the most common symptom of disease or injury and serves the purpose of calling our attention to the fact that something has gone wrong in the mechanism or condition of our body.
Under normal conditions, we are not conscious of the parts and organs of our bodies and of the work they are performing, but when affected by disease or injury, the nerves carrying pain impulses transmit a message to the spinal cord, which relays the pain sensation to the brain and we become aware of it
There are exceptional cases on record of people who do not possess these special nerves of pain sensation and are,therefore, entirely indifferent to all pain.
It is an inborn defect and exists in these persons from earliest infancy.They may be perfectly normal in every other respect and have feelings of the sensation of heat, cold, touch and pressure, but not of pain.
While the physical feeling of pain is the same in all persons possessing the pain-carrying nerves, the emotional response to pain varies greatly in different individuals.
The highly emotional response to pain as a result of worry, anxiety, fear and hysteria, may be misleading to the diagnosis by the doctor and disadvantageous to the patient