Research Article
Shirley Telles, Nilkamal Si
Abstract
Objectives: Meditation is described in traditional yoga texts as three stages, which follow each other in sequence: (i) Focused attention (FA), (ii) Focused attention on the object of meditation (MF), and (iii) Meditation with one-pointed focused attention without effort (ME). When not in meditation the mind is considered to be in a state of normal consciousness characterized by random thinking (RT). The objective of the present study was to determine the brain areas activated during the three stages of meditation compared to the control state using fMRI. Methods: Functional magnetic resonance images were acquired from twenty-six right handed meditators during MF, ME and random thinking (RT) for comparison. Ten of them were experienced (average age ± SD, 37.7 ± 13.4 years; 9 males) with 6048 hours of meditation, whereas 16 (group average age ± SD, 23.5 ± 2.3 years; all males) were less experienced, with 288 hours of meditation. During the fMRI recordings the participants practiced RT, non-meditative focused thinking (FA), MF and ME, each lasting for 2 minutes. Brain areas activated during the intervention were scanned using a 3.0-Tesla Philips-MRI scanner. Results: During the third phase of meditation (ME) the experienced meditators alone showed significant activation in the right middle temporal cortex (rMTC), right inferior frontal cortex (rIFC) and left lateral orbital gyrus (LOG) (p < 0.05), Bonferroni adjusted t-tests for unpaired data, comparing ME and random thinking. Conclusions: These changes suggest that ME is associated with sustained attention, memory, semantic cognition, creativity and an increased ability to detach mentally