General Organization of the Somatosensory System

These flashcards cover key concepts, definitions, and structures related to the somatosensory system and the perception of pain.

Adaptation

Change in sensitivity in presence of constant stimulus.

Phasic receptors

Fast-adapting receptors that send signals at the beginning or end of a stimulus.

Tonic receptors

Slow-adapting receptors that adapt slowly or not at all.

Exteroceptors

Receptors that receive input from external environment.

Proprioceptors

Receptors that monitor the position and movement of the body.

Interoceptors

Receptors that detect changes in the internal environment.

Receptor level

The level of sensory processing involving sensory receptors.

Circuit level

The processing level involving ascending pathways for sensory information.

Perceptual level

The processing level in cortical sensory areas where perception occurs.

Sensation

The awareness of changes in the internal and external environment.

Perception

The conscious interpretation of sensory stimuli.

Tactile corpuscles

Small receptors involved in discriminative touch.

Lamellar corpuscles

Large receptors that respond to deep pressure and vibration.

Feature abstraction

Identification of complex aspects and several stimulus properties.

Quality discrimination

Ability to identify submodalities of sensation, such as taste types.

Pattern recognition

Recognition of familiar or significant patterns in stimuli.

First-order sensory neurons

Neurons that conduct impulses from receptor to spinal reflexes or second-order neurons.

Second-order sensory neurons

Neurons that transmit impulses to third-order sensory neurons.

Third-order sensory neurons

Neurons that conduct impulses from the thalamus to the somatosensory cortex.

Perceptual detection

Ability to detect a stimulus requiring the summation of impulses.

Magnitude estimation

Intensity of a stimulus coded in frequency of impulses.

Spatial discrimination

Identifying the site or pattern of stimulus through tests like two-point discrimination.

Generator potential

A graded potential generated in general receptors upon stimulus excitation.

Receptor potential

A graded potential generated in special sense receptors upon stimulus excitation.

Visceral pain

Pain resulting from stimulation of visceral organ receptors, felt as vague aching.

Referred pain

Pain perceived in a different region than its actual source.

Pain tolerance

The level of pain that a person can endure.

Sensitive to pain

Low pain tolerance, meaning the person feels pain intensely.

Neurotransmitters

Chemicals released during pain transmission, such as glutamate and substance P.

Endogenous opioids

Natural pain relief substances in the body, such as endorphins.