Differentiating Noxious- and Innocuous-Related Activation of Human Somatosensory Cortices Using Temporal Analysis of fMRI
1 Department of Neurology and Neurosurgery, Faculty of Graduate Studies & Research, McGill University, Montreal, Quebec H3A 2B4; 2 Department of Physiology, Faculty of Graduate Studies & Research, McGill University, Montreal, Quebec H3G 1Y6; 3 Centre de recherche en sciences neurologiq...
Gespeichert in:
Veröffentlicht in: | Journal of neurophysiology 2002-07, Vol.88 (1), p.464-474 |
---|---|
Hauptverfasser: | , , , , |
Format: | Artikel |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | 1 Department of Neurology and
Neurosurgery, Faculty of Graduate Studies & Research, McGill
University, Montreal, Quebec H3A 2B4;
2 Department of Physiology, Faculty of Graduate
Studies & Research, McGill University, Montreal, Quebec H3G 1Y6;
3 Centre de recherche en sciences neurologiques,
Université de Montréal, Montreal, Quebec H3C 3J7;
4 Department of Neurology and Neurosurgery, and
5 Department of Anesthesiology, Faculty of
Medicine, and 6 Faculty of Dentistry, McGill
University, Montreal, Quebec H3G 1Y6; 7 McConnell
Brain Imaging Centre, Montreal Neurological Institute, Montreal, Quebec
H3A 2B4; and 8 Département de stomatologie,
Faculté de médicine dentaire, Université de
Montréal, Montreal, Quebec H3C 3J7, Canada
Chen, Jen-I,
Brian Ha,
M. Catherine Bushnell,
Bruce Pike, and
Gary H. Duncan.
Differentiating Noxious- and Innocuous-Related Activation of
Human Somatosensory Cortices Using Temporal Analysis of fMRI. J. Neurophysiol. 88: 464-474, 2002. The role of the somatosensory cortices (SI and SII) in pain perception
has long been in dispute. Human imaging studies demonstrate activation
of SI and SII associated with painful stimuli, but results have been
variable, and the functional relevance of any such activation is
uncertain. The present study addresses this issue by testing whether
the time course of somatosensory activation, evoked by painful heat and
nonpainful tactile stimuli, is sufficient to discriminate temporal
differences that characterize the perception of these stimulus
modalities. Four normal subjects each participated in three functional
magnetic resonance imaging (fMRI) sessions, in which painful (noxious
heat 45-46°C) and nonpainful test stimuli (brushing at 2 Hz) were
applied repeatedly (9-s stimulus duration) to the left leg in separate
experiments. Activation maps were generated comparing painful to
neutral heat (35°C) and nonpainful brushing to rest. Directed
searches were performed in SI and SII for sites reliably activated by
noxious heat and brush stimuli, and stimulus-dependent regions of
interest (ROI) were then constructed for each subject. The time course,
per stimulus cycle, was extracted from these ROIs and compared across
subjects, stimulus modalities, and cortical regions. Both innocuous
brushing and noxious heat produced significant activation within
contralateral SI and SII. The time course of brush-evoked responses
revealed a consistent single peak of activity, approximately 10 s
after the onset of t |
---|---|
ISSN: | 0022-3077 1522-1598 |
DOI: | 10.1152/jn.2002.88.1.464 |