PSYC 365 Chapter 8: Pain
Document Summary
Pain necessary for survival: miss c. 3 functions of pain: prevent further injury. Occurs behavior serious injury causes us to withdraw immediately: learn for the future, enforce inactivity and rest (e. g. damaged joins, abdominal infections, diseases, serious injuries. Afferent (sensory) neurons: part of pns, go to spinal cord, then brain, conduct impulses from sense organ to cns or from lower to higher levels in spinal cord and brain. Nociceptors: afferent nerve endings responding to pain stimuli, when activated: generate impulses that travel to cns. A-delta fibers: afferent peripheral fibers transmitting pain, small, myelinated transmit impulses quickly, sharp, distinct pain, strongly influence sensory aspects of pain, send messaged through the thalamus to the cerebral cortex, where a-delta fibers signal sharp pain. C-fibers: unmyelinated slower, 60% of all sensory afferents, diffuse, dull, or aching pain tend to determine affective and motivational elements of pain, send pain messages to brain stem and lower portions of the forebrain.