1. SOMATOSENSORY PHYSIOLOGY (Tactile Discrimination and Proprioception)

2. Anterolateral and Dorsal Column Systems
From Kandel,Schwartz, and Jessell, 2000, 22-14

3. SOMATOSENSORY SYSTEMS
ANTEROLATERAL SYSTEM
Light touch sensation
(light touch and crude localization)
Temperature
Nociception
(pain, tickle, itch)
DORSAL COLUMN SYSTEM
Tactile discrimination
(point localization, stereognosis)
Proprioception
(limb position and movement)

4. Mechanoreceptors
From Costanzo, 2006, Fig. 3-8

5. Berne and Levy, 1998, Fig. 8-2
Berne and Levy, 1998, Fig. 8-2

6. Receptor Types and Somatosensory Sensations

7. Point Localization
From Kandel,Schwartz, and Jessell, 2000, 21-11

8. Two Point Discrimination
From Kandel,Schwartz, and Jessell, 2000, 23-11

9. From Schmidt, 1985, Fig 2-4

10. From Kandel,Schwartz, and Jessell, 2000, 18-6

11. Receptive Fields
From Kandel and Schwartz, 1991, 25-9

12. From Berne and Levy, 1998, Fig. 9-6

13. Feature-Dectection Neurons
From Kandel,Schwartz, and Jessell, 2000, 23-13, (Adapted from Costanzo and Gardner, J. Neurophysiol. 1980)

14. Gardner and Costanzo, J. Neurophysiol. 43:1435, 1980)

15. Receptors Mediating Proprioception

16. From Berne and Levy, 1998, Fig. 9-8

17. From Berne and Levy, 1998, Fig. 9-8

18. From Costanzo and Gardner, Brain Research, 214:327,1981

19. From Costanzo and Gardner, Brain Research, 214:329,1981

20. From Gilman & Newman, 1996

21. Injury To The Dorsal Columns CLINICAL SIGNS
Loss of two-point discrimination
Loss of vibration sense
Inability to recognize limb position without visual information
Inability to recognize letters or numbers drawn on the skin (agraphesthesia)
Loss of ability to recognize objects by palpation and handling (astereognosis)
Inability to maintain posture (balance) when feet are close together and eyes closed (Positive Romberg sign)