Cerebral columnar organization of the first nociceptive component induced by CO2 laser on the tail of the rat.
Neuroscience
; 158(2): 945-50, 2009 Jan 23.
Article
in En
| MEDLINE
| ID: mdl-18952154
ABSTRACT
The somatotopic map of the first nociceptive component in the primary somatosensory cortex (S1) is still unclear. In this study, a CO(2) laser was applied to the tail of the rat to induce nociception without the interference from large myelinated (A(beta)) fibers. Thus, only noxious fibers could be activated. Two-dimensional current-source-density analysis was used to analyze the evoked field potentials. Using this method, the nociceptive responses of A(delta)-fibers in S1 were verified, and the somatotopic map of the first nociceptive component in S1 was identified. We found that whether light touch or laser-induced nociception was applied to the tail of the rat, the responsive topography in S1 was consistent. Discrimination of these two modalities was achieved vertically in the same column; the deeper layer represented the nociceptive response while the superficial layer encoded the response to light touch. This is quite different from that of a primate brain.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Pain
/
Somatosensory Cortex
/
Tail
/
Brain Mapping
/
Lasers, Gas
Limits:
Animals
Language:
En
Journal:
Neuroscience
Year:
2009
Document type:
Article
Affiliation country: