Relationship between cerebral nystagmogenic area and spinal cord.
The effect of section of the spinal cord upon the cerebral nystagmogenic area was investigated in rabbits. Cervical transection was found to result in an increase of excitability of such area, which is demonstrated by lowering of the threshold for cerebral eye nystagmus, whereas dorsal spinal transection does not affect the cerebral nystagmogenic area. Moreover, it was found that stimulation of the proximal stump of the spinal cord, at level of the dorsal quadrants, depresses the excitability of the cerebral nystagmogenic area, while ventral quadrants stimulation has a facilitating effect on the CNA. Modification of the excitability of the cerebral nystagmogenic area was also studied recording NPPs (Non-Primary Potentials) and unitary responses to photic stimulation prior to and after cervical transection as well as following dorsal and ventral quadrants stimulation. The Authors suggest that since the nystagmogenic area is located in the perivisual fields it receives visual and sensitive afferent impulses from the upper part of the body and it, in turn, projects onto the oculomotor nuclei, so that it could be considered as an integrator center for extrinsic musculature of the eye.
D000818:Animals; D002540:Cerebral Cortex / Q000502:physiology*; D004558:Electric Stimulation; D005260:Female; D008297:Male; D009760:Nystagmus, Physiologic; D010775:Photic Stimulation; D011817:Rabbits; D013116:Spinal Cord / Q000502:physiology*; D014795:Visual Pathways / Q000502:physiology