Login | Register

FMRI study of the brain correlates of hedonic and sensory perception during thermal alliesthesia

Title:

FMRI study of the brain correlates of hedonic and sensory perception during thermal alliesthesia

Bacon, Marc-André (2014) FMRI study of the brain correlates of hedonic and sensory perception during thermal alliesthesia. Masters thesis, Concordia University.

[img]
Preview
Text (application/pdf)
Bacon_MA_F2014.pdf - Accepted Version
Available under License Spectrum Terms of Access.
3MB

Abstract

This functional MRI experiment uses the alliesthesia phenomenon to map the brain correlates of hedonic experience and sensation. Alliesthesia refers to the dependence of the hedonic impact of a stimulus on the ‘milieu interne’. Thus, a thermal stimulus applied to the skin during hyperthermia or hypothermia should be perceived as having the same temperature but opposite hedonic impact. Twenty participants took part in two successive scanning sessions during which mild states of hyperthermia and hypothermia were induced. Participants wore a water-perfused suit consisting of a long-sleeved shirt and trousers. In two of the stimulus conditions, either cold or hot water perfused the suit; in the third ‘neutral’ condition, water flow was interrupted. At intervals of 9 seconds, the participants rated, on two Likert scales, the thermal sensation perceived (from hot to cold) and the corresponding hedonic experience (from unpleasant to pleasant).Three different regressors were built from the ratings: hedonic, homeostatic, and sensory. The hedonic regressor was derived from the pleasantness ratings, whereas the sensory regressor was derived from the temperature ratings. The homeostatic regressor was also derived from the temperature ratings, but the sign was adjusted to conform to the value that would oppose the deviation of core temperature. Application of the hedonic and homeostatic regressors revealed conjoint activations in the more lateral areas of the orbitofrontal cortex. Application of the sensory regressor revealed clusters of activation, mainly in the middle frontal gyrus, the superior frontal gyrus, the precentral gyrus, and the right orbitofrontal cortex.

Divisions:Concordia University > Faculty of Arts and Science > Psychology
Item Type:Thesis (Masters)
Authors:Bacon, Marc-André
Institution:Concordia University
Degree Name:M.A.
Program:Psychology
Date:June 2014
Thesis Supervisor(s):Shizgal, Peter
ID Code:978782
Deposited By: MARC-ANDRE BACON
Deposited On:07 Nov 2014 16:39
Last Modified:18 Jan 2018 17:47
All items in Spectrum are protected by copyright, with all rights reserved. The use of items is governed by Spectrum's terms of access.

Repository Staff Only: item control page

Downloads per month over past year

Research related to the current document (at the CORE website)
- Research related to the current document (at the CORE website)
Back to top Back to top