Neuroimaging Using the Magnetoencephalography - Article Example

Studies on neuro-imaging using magneto-encephalography and positron emission tomography had provided sufficient knowledge to prove that the pain matrix in the brain was the seat of a complex response to pain. However, the brain response had not yet been demonstrated by the neuro-imaging technique of functional magnetic resonance imaging. The pain response following different types of meditation was different. Orme-Johnson and his team have specified four mechanisms to reduce pain:
“(1) distract attention away from it; (2) resolve the underlying physiological condition responsible for chronic pain; (3) reduce anticipatory anxiety and general stress reactivity and other factors that amplify the pain response; and (4) reduce pain-related distress, perhaps through increasing endogenous endorphins.”
Transcendental meditation was found to use the latter three of the four techniques mentioned. Meditation programs reduced pain problems, general aches in the body, and headaches through physiological resolution.

Orme-Johnson’s study indicated that meditation could induce a long-term effect of decreased responses in the pain matrix, especially the affective component. Distress, if reduced, could lower the response of the pre-frontal cortex. The thalamus also showed a reduced response. Orme-Johnson’s study had a partial crossover design and it was approved at the University of California. 12 men and 12 women, all right-handed, healthy, and pain-free constituted the sample. Twelve normal, healthy right-handed people above 45 years who wished to learn transcendental meditation were introduced to the research and constituted the healthy controls. The people who were practicing transcendental meditation for around 31.3 years were long-term meditators. The intervention was a four-day course of transcendental meditation for 20 minutes twice daily. The functional magnetic resonance imaging was done at pre-test and post-test 5 months afterward. The neural activity when the finger was immersed in hot water or warm water was the test employed. The response was the increase in the Blood Oxygen Level Dependent signal intensity above a threshold. Spatial normalization was done according to the Montreal Neurological Institute brain. The two-way ANOVA was used to analyze the data. The Pain Visual Analogue was used to assess psychophysiological response. The pain ratings were reduced in both groups from pre-test to post-test but the fMRI responses of the brain were different. In the post-test however, no obvious difference was evident between the groups. The conclusion was that the pain intensity and the brain response did not co-vary as expected; transcendental meditation produced less distress even though the intensity of pain was high. The biggest change was seen in the anterior cingulate cortex (the brain area for mediating effect) for the controls after learning meditation. The only limitation of this study was the self-selection of participants. Otherwise, the internal validity was high. The reduction of the brain response could be attributed to the reduction in the expectation of anxiety or distress. Read More