Clinical hypnosis modulates functional magnetic resonance imaging signal intensities and pain perception in a thermal stimulation paradigm.
OBJECTIVE
This study was designed to describe regional changes in blood oxygenation level dependent signals in functional magnetic resonance images (fMRI) elicited by thermal pain in hypnotized subjects. These signals approximately identify the neural correlates of the applied stimulation to identify neuroanatomic structures involved in the putative effects of clinical hypnosis on pain perception.


METHODS
After determination of the heat pain threshold of 12 healthy volunteers, fMRI scans were performed at 1.5 Tesla by using echoplanar imaging technique during repeated painful heat stimuli. Activation of brain regions in response to thermal pain during hypnosis (using a fixation and command technique of hypnosis) was compared with responses without hypnosis.


RESULTS
With hypnosis, less activation in the primary sensory cortex, the middle cingulate gyrus, precuneus, and the visual cortex was found. An increased activation was seen in the anterior basal ganglia and the left anterior cingulate cortex. There was no difference in activation within the right anterior cingulate gyrus in our fMRI studies. No activation was seen within the brainstem and thalamus under either condition.


CONCLUSIONS
Our observations indicate that clinical hypnosis may prevent nociceptive inputs from reaching the higher cortical structures responsible for pain perception. Whether the effects of hypnosis can be explained by increased activation of the left anterior cingulate cortex and the basal ganglia as part of a possible inhibitory pathway on pain perception remains speculative given the limitations of our study design.
Schulz-Stübner
Sebastian
S
Department of Anesthesia, University of Iowa Hospitals and Clinics, 200 Hawkins Drive, 6 JCP, Iowa City, IA 52242-1079, USA. Sebastian-schulz-stubner@uiowa.edu
Krings
Timo
T
Meister
Ingo G
IG
Rex
Stefen
S
Thron
Armin
A
Rossaint
Rolf
R
D001921:Brain / Q000473:pathology / Q000502:physiology*; D001931:Brain Mapping; D017352:Echo-Planar Imaging; D006358:Hot Temperature; D006801:Humans; D006990:Hypnosis; D010100:Oxygen / Q000097:blood; D010146:Pain / Q000175:diagnosis / Q000503:physiopathology; D017288:Pain Threshold / Q000502:physiology*; D010465:Perception
D010100:Oxygen