1. Sensory Physiology 10

2. Nociceptors Free nerve ending
Respond to strong noxious stimulus that may damage tissue
Modulated by local chemicals
Substance P is secreted by primary sensory neurons
Mediate inflammatory response
Inflammatory pain

3. Nociceptors Pathways Reflexive protective response
Integrated in spinal cord
Withdrawal reflex
Ascending pathway to cerebral cortex
Becomes conscious sensation (pain or itch)

4. Somatosensory Nerve Fibers

5. Nociceptors: Pain and Itch
Histamine activates C fibers causing itch
Pain
Subjective perception
Fast pain
Sharp and localized—by A fibers
Slow pain
More diffuse—by C fibers

6. The Gate-Control Theory of Pain
Figure 10-12a

7. The Gate-Control Theory of Pain
Figure 10-12b

8. The Gate-Control Theory of Pain
Figure 10-12c

9. Pain: Referred Pain
Figure 10-13b

10. Pain Ischemia Chronic pain is a pathological pain Analgesic drugs
Lack of adequate blood flow
Chronic pain is a pathological pain
Analgesic drugs
Aspirin
Inhibits prostaglandins and slows transmission of pain to site of injury

11. Olfaction Link between smell, memory, and emotion
Vomeronasal organ (VNO) in rodents
Response to sex pheromones
Olfactory cells
Olfactory epithelium in nasal cavity
Odorants bind to odorant receptors, G-protein-cAMP-linked membrane receptors

12. Anatomy Summary: The Olfactory System
Figure 10-14a

13. Anatomy Summary: The Olfactory System
Figure 10-14b

14. Anatomy Summary: The Olfactory System
Figure 10-14c

15. Summary of Taste Transduction
Figure 10-16

16. Summary of Taste Transduction
Figure (1 of 5)

17. Summary of Taste Transduction
Figure (2 of 5)

18. Summary of Taste Transduction
Figure (3 of 5)

19. Summary of Taste Transduction
Figure (4 of 5)

20. Summary of Taste Transduction
Figure (5 of 5)

21. Summary of Taste Transduction
Humans and animals may develop specific hunger such as salt appetite
Figure 10-16

22. Taste Buds
Figure 10-15a–b

23. Anatomy Summary: The Ear
The ear is a sense organ that is specialized for two functions: hearing and equilibrium
Figure 10-17

24. Sound Waves Hearing is our perception of energy carried by sound waves
Figure 10-18a

25. Sound Waves
Figure 10-18b

26. Sound Transmission Through the Ear
Figure (1 of 6)

27. Sound Transmission Through the Ear
Figure (2 of 6)

28. Sound Transmission Through the Ear
Figure (3 of 6)

29. Sound Transmission Through the Ear
Figure (4 of 6)

30. Sound Transmission Through the Ear
Figure (5 of 6)

31. Sound Transmission Through the Ear
Figure (6 of 6)

32. Anatomy Summary: The Cochlea
Figure (1 of 2)

33. Anatomy Summary: The Cochlea
Perilymph in vestibular and tympanic duct
Similar to plasma
Endolymph in cochlear duct
Secreted by epithelial cells
Similar to intracellular fluid

34. Anatomy Summary: The Cochlea
Figure (2 of 2)

35. Signal Transduction in Hair Cells
The apical hair cell is modified into stereocilia
Figure 10-21a

36. Sensory Coding for Pitch
Figure 10-22a

37. Sensory Coding for Pitch
Figure 10-22b

38. The Ear: Auditory Pathways
Waves
Electrical signals in cochlea
Primary sensory neurons to brain in medulla oblongata
Sound projected to nuclei
Main pathway synapses in nuclei in midbrain and thalamus
Auditory cortex