Chapter 6 Class Outline

Gate Control Theory

• A theory that explains the mechanisms of pain perception.

• Suggests that the spinal cord contains a neurological "gate" that either opens to allow pain signals to reach the brain or closes to prevent them.

Pain Physiology

• Understanding the physiological processes involved in the sensation of pain.

Peripheral Nervous System

• A Delta fibers:

  • Myelinated nerve fibers.

  • Responsible for transmitting sharp and acute pain signals.

  • They allow for quick reflex actions in response to harmful stimuli.

• C Fibers:

  • Unmyelinated nerve fibers.

  • Transmit dull, throbbing, or aching pain signals that are slower to reach the brain.

Central Nervous System

• Involves the brain and spinal cord, where pain signals are processed.

• Limbic System:

  • Part of the brain that processes emotions and may influence pain perception and response.

• Substance P:

  • A neuropeptide involved in the transmission of pain signals in the nervous system.

  • It is released from sensory neurons and plays a role in pain modulation.

• Glutamate:

  • A neurotransmitter that is also implicated in pain signaling, particularly in the spinal cord.

Processes at the Descending Nerve Fibers

• Refers to how the brain can modulate incoming pain signals through descending pathways.

Types of Pain

• Understanding different classifications of pain can inform treatment approaches.

Acute Pain

• Short-term pain that typically arises suddenly due to an injury or illness.

• Usually resolves once the underlying cause is treated.

Chronic/High Impact Chronic Pain

• Long-lasting pain that persists beyond normal healing time, often associated with conditions such as arthritis or fibromyalgia.

• Can significantly affect a person's quality of life.

Neuropathic Pain

• Pain caused by damage or dysfunction within the nervous system.

• Often described as shooting, burning, or tingling sensations.

Nocioplastic Pain

• Pain arising from altered nociception despite no clear evidence of injury or damage.

Windup

• A phenomenon where repeated stimulation of nociceptors leads to an increased response to pain over time.

Peripheral Sensitization

• Increased sensitivity to pain in the peripheral nervous system, usually following an injury.

Central Sensitization

• Increased sensitivity to pain in the central nervous system, which can occur even in the absence of ongoing injury.