Susan C Feldman PhD, Presenter: Nothing to Disclose

Aphrodite M Zimmerman, Abstract Co-Author: Nothing to Disclose

Ourania Nasis, Abstract Co-Author: Nothing to Disclose

Wen-Ching Liu PhD, Abstract Co-Author: Nothing to Disclose

Acupuncture-induced activity has been the focus of several recent fMRI studies. Little is known about the temporal patterns of CNS activity underlying acupuncture. Therefore,we developed a stimulation and analysis paradigm to characterize CNS activity patterns that might otherwise be undetectable.

Seven adults were studied. Strong mechanical stimulation (twisting)was delivered to the LI4 acupoint or to a non-acupoint. Stimulation was given for 30 minutes in a sequence of 30 seconds ON/30 seconds OFF. Controls were run separately. Subjects were scanned in a 1.5T GE scanner; data was analyzed using IDL and SPM99 software. Images were projected onto Talairach brain space. Each 30 second ON scan was analyzed separately. In each scan we identified the active areas; for each active area we measured the activation volume and peak intensity.

Acupuncture activated several cortical and subcortical areas. Our paradigm allowed us to identify two distinct temporal activity patterns: a cortical pattern and a subcortical pattern. Cortical areas 1,2,3,5,24,31,40 were active more than 90% of the time with no appreciable decline in frequency or intensity over the 30 minutes. In the subcortical areas- including thalamus, hippocampus, amygdala, periaqueductal gray, substantia nigra- the activity pattern was quite different. First, each area was only sporadically active. Second, by 15-25 minutes there was an overall increase in subcortical activity with no change in intensity. Third, by the end of the study, 30 minutes, there was a pronounced decline in the activity of all subcortical areas often below initial levels. Stimulation of a non-acupoint resulted in similar activity patterns but activity was still more infrequent and intensity levels were somewhat reduced.

Our results suggest that acupuncture induces two different CNS activity patterns. This modified paradigm - involving long stimulation times and analysis of individual scans - should also be useful in demonstrating activity patterns in other CNS areas that would otherwise be obscured.

Feldman, S, Zimmerman, A, Nasis, O, Liu, W, Temporal Patterns of Acupuncture-induced Activity in Cortical and Subcortical Areas: An fMRI Study.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4406742.html