Study Guide for Chapter 13

1.         Besides helping with object identification and supporting our posture and movement, what are other roles played by touch?

2.         Why do your authors suggest that touch can be construed as the most reliable of the sensory modalities?

3.         What are Von Frey hairs used for?

4,         What is the best range of frequencies to use when applying a vibrating stimulus?

5.         How might vibrotactile stimulation be used in a clinical or applied setting?

5.         How might you measure touch acuity?

6.         What features combine to create high localization ability?

7.         What is the critical feature of texture discrimination by the fingers?

8.         Why are embossed letters more difficult to read than Braille characters?

9.         What does short-term memory have to do with the fact that  visual recognition is superior to recognition by touch?

10.       What are you actually perceiving when you perceive the “touch temperature” of  an object?

11.       Why does metal feel cooler than wood when both are at room temperature?

12.       What is the purpose for which your authors note that more than 35,000 women in North America die per year as the result of breast cancer?

13.       What properties of response patterns give rise to the four categories developed by Valbo and Hagbarth (1968)? In other words, what are those categories and what   

            characteristics does each involve?

14.       Which of the four groups above gives a response to very light touch? What about a relatively strong stimulus?

15.       Describe the following types of receptors according to their structure and function: Meissner corpuscles, Merkel disks, Ruffini endings, Pacinian corpuscles, and free nerve endings (also hair follicle receptors, which are really a version of free nerve endings).

16.       Describe/diagram the ascending touch pathway (the dorsal column-medial lemniscal pathway). How does this pathway give rise to the contralateral mapping of the somatosensory cortex?

17.       Where is the primary somatosensory cortex located?

18.       What is tactile agnosia?

19.       Does the somatosensory cortex display topographical mapping? How are very sensitive areas distributed compared to less sensitive ones? How does this mapping relate to receptive fields for the receptor end-organs?

20.       Do cortical neurons in the somatosensory cortex display orientation and direction preferences in the same way that neurons in the visual cortex do?

21.       What is kinesthesis?

22.       In what way is kinesthesis essential for haptic ability?

23.       What are the characteristics necessary to allow people to disciminate objects haptically?

24.       Is vision a necessary ability in order to develop object discrimination via touch? (In other words, do blind children learn object discrimination through haptics?)

25.       What is phantom limb syndrome? What do you think is the neural source of phantom limbs?

26.       Describe the various ways of measuring pain (e.g., what are the most common types of pain scales?).

27.       What are nociceptors?

28.       Describe the pathway that the pain message travels from nociceptor to brain, including the types of fibers.

29.       Describe/diagram the “gate control” theory of pain.

30.       What are “top down” influences on pain perception?

31.       Is the sensory cortex modifiable by experience? What evidence supports this? How might this have clinical applicability?