Chapter 7 - Somatosensory System Flashcards
The somatosensory system is made of three separate but interacting systems:
- Exteroceptive system
- Proprioceptive system
- Interoceptive system
Exteroceptive system
Senses external stimuli that are applied to the skin.
Proprioceptive system
Monitors information about position of the body that comes from receptors in the muscles, joints, and organs of balance.
Interoceptive system
Provides general information about conditions within the body (e.g., temperature and blood pressure).
Three divisions of the exteroceptive system.
A division for perceiving mechanical stimuli (touch), one for thermal stimuli (temperature), and one for nociceptive stimuli (pain).
- touch
- temperature
- pain
Free nerve endings
Neuron endings with no specialized structures on them, which are particularly sensitive to temperature change and pain.
Pacinian corpuscles
The largest and most deeply positioned cutaneous receptors, which are sensitive to sudden displacements of the skin.
Because they adapt rapidly, they respond to sudden displacements of the skin but not to constant pressure.
Stereognosis
The process of identifying objects by touch.
Dermatome
The area of the body that is innervated by the left and right dorsal roots of a given segment of the spinal cord.
Innervate
supply (an organ or other body part) with nerves.
Astereognosia
The inability to recognize objects by touch.
Asomatognosia
The failure to recognize parts of one’s own body.
Olfactory glomeruli
Discrete clusters of neurons on the surface of the olfactory bulbs; each neuron in a particular cluster contains the same type of receptor protein.
Olfactory bulbs
The first cranial nerves, whose output goes primarily to the amygdala and piriform cortex.
Olfactory mucosa
The mucous membrane that lined the upper nasal passages and contains the olfactory receptor cells.
