Chapter 1 & 2: Sense Of Pain and Located Sharp Pain

Chapter 1: Sense Of Pain

Section Overview

• Objectives of this section include:
    - Describing the sense of pain and pain disorders.
    - Describing kinesthesis and disorders of kinesthesis.
    - Describing the vestibular sense and disorders of the vestibular system.

The Sense of Pain

• Pain is defined as the body's natural defense mechanism:
    - Alerts the body to danger.
    - Signals the presence of injury.
    - Alerts the body to disease.

Perception of Pain

• The experience of pain is influenced by a person's perception or awareness of noxious stimuli.
• Noxious stimuli are defined as any stimuli that can cause damage or potential damage to the body and can be categorized as:
    - Mechanical
    - Chemical
    - Thermal
• Abundance of certain stimuli can also activate pain senses:
    - For instance, the body can tolerate certain heat levels; exceeding this can result in pain.

Receptors for Pain

• Pain receptors consist of free nerve endings originating from the spinal cord:
    - Located throughout the body, excluding the brain.
    - Detect chemicals released from painful stimuli.
    - Trigger neural signals in response to pain.
• Nerve fibers are responsible for carrying these neural signals from pain receptors to the spinal cord:
    - Different types of fibers are activated based on the type of pain experienced.

Chapter 2: Located Sharp Pain

Types of Pain Fibers

• A delta fibers:
    - Associated with specifically located sharp pain.
• C fibers:
    - Associated with dull aches and pains.

Pathway to the Brain

• Pain signals follow a specific pathway:
    - From nerve fibers, up the spinal cord to the thalamus.
    - The thalamus then relays the signals to other areas of the brain for further processing.

Theories of Pain Processing

• Currently, no single theory fully explains all aspects of pain experience and modulation.
• Gate Control Theory:
    - A theory that attempts to elucidate how pain sensation is modulated by the spinal cord.
    - Suggests that the spinal cord contains a "gate" that can be opened or closed to regulate the pain signals sent to the brain, influencing the experience of pain directly correlating its intensity to various physical and environmental factors.