POSTER PRESENTATION ABSTRACTS
Please note: All posters will be displayed in
Salons 10-12.
THURSDAY, 10:15-11:00 AM
Zaki J, Vilarroya O, Carmona S, Valencia J, Rovira M,
Benson H, Lazar SW, Dusek JA.
Network of brain regions activated during subjects' first
relaxation response eliciting meditation.
Mind/Body Medical Institute and Columbia University
jamil@psych.columbia.edu
PURPOSE: Previous neuroimaging studies have
identified both functional and structural changes in long-term meditators.
No studies, however, have evaluated whether similar neural regions or
circuitry are engaged during na•ve subjects' first relaxation response
(RR) eliciting meditation experience.
METHODS: 19 healthy Ss were recruited from the
Barcelona area and screened to ensure no prior mind/body or meditation
practice. Images were collected using a 1.5T MRI scanner while Ss listened
to a 9-minute control audiotape and an 18-minute RR-eliciting meditation
audiotape. In the control condition, Ss listened to a book excerpt and
were asked to count the number of proper nouns they heard, which matched
the attentional demands of the meditation conditions. During RR-meditation,
Ss listened to the same voice, this time guiding them through a standard
meditation practices (9 minutes of bodily focused relaxation, 9 minutes
of focused attention practice). After exiting the scanner, subjects
gave written reports of what they had heard to confirm their wakefulness
during the scan session. Within-subject and group-level random effects
analyses were conducted in SPM2; differences in activation between the
control condition and meditation periods were significance thresholded
at p< .0005 (uncorrected), and extent thresholded at a minimum 15 contiguous
voxels/cluster.
RESULTS: A broad network of activation distinguished
the meditation from the control condition, which included the superior
portion of the left anterior insula (lAI), the right posterior insula
(rPI), inferior medial frontal gyrus (rMFG), left middle frontal gyrus
(lMiFG) right superior temporal gyrus (rSTG), left parahippocampal gyrus,
bilateral precuneus, and the right putamen. Further analyses revealed
no significant differences in activation between the different meditation
conditions. Some areas showed trends towards stronger activation in
later conditions, which might suggest a cumulative session effect.
CONCLUSIONS: Many brain regions identified in
the current study correspond with those from a previous fMRI study of
long-term kundalini practitioners (parahippocampal gyrus, MFG, MiFG,
putamen, STG), suggesting that some of the structural and functional
changes observed in long-term meditation practitioners may be based
on repeated induction of mental states observable the very first time
subjects meditative states using standard practices. Differences in
activation between these studies could point to differences between
the types of attention deployed during different types of meditation.
Observed activation of the precuneus and MFG in our study suggests deployment
of internally focused attention also engaged during normal rest, with
additional components of motivation (as suggested basal ganglia activation)
and bodily awareness (subserved by the PI). This circuitry may reflect
basic, focused relaxation employed in early meditation. Nonetheless,
our data dovetail at many points with work on experienced meditators
in disparate traditions, suggesting important underlying similarities
across experience and practice-type. Our data provide the first empirical
evidence that the brain activation changes associated with meditation
and the RR likely begin with individuals' first experience.
Back