In each experiment, participants who had not previously practiced relaxation or meditation received either IBMT or general relaxation instruction for 20 minutes a day for five days. While both groups experienced some benefit from the training, those in IBMT showed dramatic differences based on brain-imaging and physiological testing.
Single photon emission computed tomography (SPECT) -- a scanning method less distracting than functional magnetic resonance imaging (fMRI) -- showed IBMT subjects had increased blood flow in the right anterior cingulate cortex, a region associated with self regulation of cognition and emotion.
Physiological tests also revealed significant changes. Compared with the relaxation group, IBMT subjects had lower heart rates and skin conductance responses, increased belly breathing amplitude and decreased chest respiration rates, all of which, researchers wrote, "reflected less effort exerted by participants and more relaxation of body and calm state of mind."
Finally, researchers noted, IBMT subjects had more high-frequency heart-rate variability than their relaxation counterparts, indicating "successful inhibition of sympathetic tone and activation of parasympathetic tone [in the autonomic nervous system]." Sympathetic tone becomes more active when stressed.
Preliminary findings of a recently completed but unpublished UO study involving a small group of U.S. students are showing nearly identical results, Posner said. The UO study used fMRI rather than SPECT. A much larger UO study is in progress.
IBMT avoids struggles to control thought, relying instead on a state of restful alertness, allowing for a high degree of body-mind awareness while receiv
|Contact: Jim Barlow|
University of Oregon