2. Encapsulated nerve endings:
- Dendrites enclosed in connective tissue capsule for pressure. Vibration, and some
3. Separate sensory cells:
- Specialized cells that respond to stimuli.
- Receptor cells synapse with first-order sensory neurons; located in the retina of the
eye (photoreceptors), inner ear (hair cells), and the taste buds of the tongue
(gustatory receptor cells).
- Vision, taste, hearing, and balance
• Classification by Location:
- Located at or near the body surface; they are sensitive to stimuli that originate
outside of the body (external environment).
- They provide information regarding the external environment, and will convey
visual, smell, taste, touch, pressure, vibration, thermal, and pain sensations.
- Located in blood vessels, visceral organs, and nervous system.
- They provide information regarding the internal environment.
- Impulses that are produced are usually not consciously perceived but may
occasionally be felt as pain or pressure.
- Located in the muscles, tendons, joints, and the inner ear.
- They provide information regarding body position, muscle length and tension,
position and motion of joints, and equilibrium (balance).
• Classification by the Detected Stimuli:
- Receptors that detect mechanical stimuli.
- They provide sensations of touch, pressure, vibration, proprioception, and hearing
- They also monitor the stretching of blood vessels and the internal organs.
- Receptors that detect changes in temperature
- Receptors that respond to painful stimuli resulting from physical or chemical damage