Functional imaging of central mechanisms underlying human pain perception
by Nebel, Mary Elizabeth, Ph.D., THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL, 2010, 118 pages; 3433413

Abstract:

Investigations of human somatosensory perception have demonstrated robust interactions between the submodalities of pain and touch, and there is increasing recognition that the systematic assessment of somatosensory perception in disorders characterized by persistent pain such as Temporomandibular Disorder (TMD) would greatly aid diagnosis and evaluation of treatment efficacy. To better understand the pathophysiological mechanisms underlying TMD, we investigated cortical processing interactions that occur between innocuous and noxious cutaneous input using functional magnetic resonance imaging (fMRI). Innocuous vibrotactile stimulation and noxious skin heating were delivered separately and concurrently to the hand of women with TMD and to pain-free, gender-matched controls (HC). Cortical responses evoked by innocuous vibrotactile stimulation alone differentiated TMDs from HCs, and the differences between the groups suggest cortical plasticity in TMD which primes areas to respond to innocuous vibrotactile input that normally would not, including parts of the pain matrix and auditory cortex. In contrast, pain ratings and cortical responses to noxious heat alone did not differ significantly between TMDs and HCs. However, additional group differences emerged in the cortical patterns characterizing interactions between somatosensory submodalities in subjects with and without TMD during concurrent stimulation that could not be explained exclusively by group differences in the response to innocuous vibrotactile stimulation. Some of these differences in the interaction of innocuous and noxious somatosensory inputs were correlated with the severity of the TMD patients’ clinical pain despite the fact that no significant correlations were observed between TMD pain and responses to vibrotactile or noxious heat stimulation alone. This suggests that cortical processing interactions between somatosensory submodalities more closely reflect individual experiences of persistent clinical pain than does the unimodal processing of innocuous vibrotactile or noxious heat input alone.

 
AdvisersMark Tommerdahl; Gregory Essick
SchoolTHE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL
SourceDAI/B 72-02, p. , Jan 2011
Source TypeDissertation
SubjectsNeurosciences; Biomedical engineering
Publication Number3433413
Adobe PDF Access the complete dissertation:
 

» Find an electronic copy at your library.
  Use the link below to access a full citation record of this graduate work:
  http://gateway.proquest.com/openurl%3furl_ver=Z39.88-2004%26res_dat=xri:pqdiss%26rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation%26rft_dat=xri:pqdiss:3433413
  If your library subscribes to the ProQuest Dissertations & Theses (PQDT) database, you may be entitled to a free electronic version of this graduate work. If not, you will have the option to purchase one, and access a 24 page preview for free (if available).

About ProQuest Dissertations & Theses
With over 2.3 million records, the ProQuest Dissertations & Theses (PQDT) database is the most comprehensive collection of dissertations and theses in the world. It is the database of record for graduate research.

The database includes citations of graduate works ranging from the first U.S. dissertation, accepted in 1861, to those accepted as recently as last semester. Of the 2.3 million graduate works included in the database, ProQuest offers more than 1.9 million in full text formats. Of those, over 860,000 are available in PDF format. More than 60,000 dissertations and theses are added to the database each year.

If you have questions, please feel free to visit the ProQuest Web site - http://www.proquest.com - or call ProQuest Hotline Customer Support at 1-800-521-3042.