Brain activation related to affective dimension during thermal stimulation in humans: a functional magnetic resonance imaging study.
The aim of this study was to identify the activated brain region that is involved with the affective dimension of thermal stimulation (not pain, but innocuous warming) using functional MR imaging. Twelve healthy, right-handed male subjects participated in the study. Thermal stimulation with two different temperatures of 41 degrees C and 34 degrees C was applied to the subjects using a fomentation pack, wrapped around the right lower leg of each subject. On the basis of the subjects' responses after the scanning sessions, the authors were able to observe that the subjects felt "warm" and "slightly pleasant and comfortable" under the 41 degrees C condition. The experimental results indicated that warm stimulation produced a significant increase of activation compared to thermal neutral stimulation in various regions such as contralateral insular, ipsilateral cerebellum, ipsilateral putamen, contralateral middle frontal gyrus, ipsilateral inferior frontal gyrus, contralateral postcentral gyrus, and contralateral paracentral lobule. The activated regions are known to be related to thermal sensory, affective/emotional awareness, cognitive functions, sensory-discrimination, and emotion/affective processing, and so on. These results suggest that an appropriate thermal stimulation can produce a positive emotion and activate emotion/affect related regions of the brain.
Sung
Eun-Jung
EJ
Office of Policy, Korea Research Institute of Standards and Science, Daejeon, Republic of Korea.
Yoo
Seung-Schik
SS
Yoon
Hyo Woon
HW
Oh
Sung-Suk
SS
Han
Yeji
Y
Park
Hyun Wook
HW
D000328:Adult; D000339:Affect / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D006358:Hot Temperature; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010812:Physical Stimulation / Q000379:methods; D012016:Reference Values; D013697:Thermosensing / Q000502:physiology*