Chapter 7: The Non-Visual Sensory Systems
Module 7.2- The Mechanical Senses
Module 7.3: The Chemical Senses
PART 2: The Mechanical Senses
Mechanical Senses
Vestibular Sensation
Otolith organs
Semicircular Canal
Somatosensation
Free nerve endings
Meissner's corpuscles
Pacinian Corpuscles
endorphin
Ruffini Endings
Krause End Bulbs
Dermatome
Periqueductal Gray
Substance P
Capsaicin
Gate theory
analgesia
TENS
Questions & Concepts:
1. General what sorts of sensory experience are captured by the mechanical senses?
2. What is vestibular sensation? Give an example of their usefulness in day to day activity. How does
the anatomical structure of the vestibular system (specifically the otolith organs and semicircular
canals) contribute to the vestibular senses? Where in the brain do action potentials from the
vestibular system travel?
3. What is somatosensation? Name 5 receptors conveying different types of somatosensory data and
the quality of sensensory information that they respond to
4. What are the 5 group of spinal nerves that make up the 31 spinal nerve segments? How is this
question related to the concept of a dermatome?
5. What type of sensory information does the somatosensory cortex convey?
6. How is pain a healthy somatosensory signal? How does pain relate to the neurotransmitter,
substance P.
7. How does "Ben Gay" lead to decreased pain sensation in sore muscle areas?
8. How does the gate theory of pain explain how "rubbing a boo-boo" will make it better? How do
acupuncture and TENS units support this theory
9. How do endorphins regulate substance P release, and subsequently pain. What types of pain are
most responsive to endorphin mediated analgesia.
PART 3: The Chemical Senses
Label-line principle
Across-fiber pattern principle
Taste Buds & Papillae
Supertasters
Vomeronasal organ (VNO)
Adaptation & Cross-Adaptation
NTS
Olfaction and Olfactory Cells
Anosmia/specific anosmia
pheromones
Questions & Concepts:
1. Why is a chemical sensitivity thought to the first sense developed by early creatures
2. Differentiate between label-line and across-fiber pattern principles of chemical coding. How does this
relate to taste and olfaction?
3. Describe the lifetime and structure and location of taste buds.
4. What are the four known types of taste receptors? How do they code chemical information into a
"whole sensory experience"?
5. How do the terms adaptation and cross-adaptation relate to taste experience?
6. Describe the neural mechanisms of action for producing salty and sour taste sensations and the
neural pathways carrying these signals.
7. Describe the structure and location of olfactory cells.
8. What evidence is there that humans have a large number of "primary" smell sensations?
9. What is the VNO and what is its function in humans and many non-human animals?