pain and pain gate theory.pptx

knowledge about pain and pain gate theory

1. PAIN AND PAIN GATE THEORY P resented by: Priyanka B husal

2. Pain is defined as unpleasant sensory and emotional experience associated with actual or potential tissue damage . PAIN DEFINITION:

3. Gate control theory was described by Melzack and Wall in 1965. This theory explains about a pain-modulating system in which a neural gate present in the spinal cord can open and close thereby modulating the perception of pain .  PAIN GATE THEORY:

4. The substantia gelatinosa in the dorsal horn The dorsal column fibers The central transmission cells . The three systems located in the spinal cord act to influence perception of pain are:

5. The dorsal horn is responsible for passing on information which can be interpreted as pain. This area is referred to as the 'gate' as it prevents the brain from receiving too much information too quickly. GATE= Dorsal horn

6. Primary: from the ‘ nociceptors ’ to the dorsal horn of the spinal cord. Secondary: from the dorsal horn to the thalamus. Tertiary : from thalamus to cortex and awareness. NEURONS INVOLVED IN PAIN CONDUCTION ARE:

7. The smaller, unmyelenated A (delta) and C nerve fibers sense pain such as sharp burning and aching feelings. Larger, myelenated A (beta) skin nerves which carry senses of touch, heat, cold and pressure. • The A (beta) nerves are faster, and also have priority which effectively blocks out the pain messages to the brain and closes the gate. NERVE FIBERS INVOLVED ARE:

8.   Stimulation of the large-diameter fibers (A-Fibers ) activates inhibitory interneuron which inhibits the transmission of pain (closing the gate ). Stimulation of the Small-diameter fibers (C-Fibers) stimulates the transmission of pain (opening the Gate ). When the gate is closed, signals from small diameter pain fibers do not excite the dorsal horn transmission neurons. When the gate is open pain signals excite dorsal horn transmission cells. The gating mechanism is influenced by nerve impulses that descend from the brain.

9. The amount of activity in the pain fibers. The amount of activity in other peripheral fibers Messages that descend from the brain. FACTORS INFLUENCING OPENING AND CLOSING OF GATE:

10. Physical Pain - Analgesic Remedies Emotional Pain - Being in a ‘good’ mood Behavioral Factors - Concentrating on things other than the injury Relaxation and Contentment Mental factors: work, T.V., book, Activity - Taking exercise counter-stimulation- heat, massage, acupuncture GATE IS CLOSED BY:

11. Physical Factors - Bodily injury Emotional Factors - Anxiety & Depression Behavioral Factors - Attending to the injury and concentrating on the pain Lack of Activity GATE IS OPENED BY: