Acupuncturists outperform non-acupuncturists (NA) in tests of behavioural skills associated with their profession and this is reflected in structural differences in their brains. Chinese researchers recruited a cohort of 22 acupuncturists and compared them with 22 non-acupuncturists. In the first set of experiments, tests designed to assess fine motor skill for fingers and tactile spatial discrimination were administered to both groups. Acupuncturists scored better on both tests. A further test was administered to examine the ability of subjects to regulate their emotional responses to images of painful situations. The results of this experiment showed that while unpleasantness ratings for neutral stimuli did not differ between the two groups, for negative stimuli, unpleasantness ratings were significantly lower among the acupuncturists. This demonstrated that the acupuncturists had better emotional regulation ability than controls. In order to see if these behavioural differences were correlated with structural differences in the brain, the researchers used fMRI scanning. Acupuncturists were found to have more grey matter in the left primary somatosensory cortex (SI), a brain region known to play an important role in the perception of touch. In addition, a region of the cerebellum (right lobule V/VI) associated with fine motor control of the fingers also appeared to contain more grey matter in acupuncturists. Grey matter volumes in these areas were positively correlated with duration of acupuncture practice, providing evidence that neuroplastic changes are induced in the brain in response to the manual skills involved in acupuncture practice. Finally, the scientists found that acupuncturists had a larger grey matter volume in a brain region involved in modulation of emotional responses (the bilateral ventral anterior cingulate cortex/ventral medial prefrontal cortex). This region is specifically associated with suppressing or reappraising negative emotional stimuli and with suppressing the influence of negative emotional stimuli on subsequent behaviour. Increased GMV in this region has previously been associated with enhanced emotional regulation in long-term practitioners of meditation. The authors hypothesise that brain changes in this region are the neural correlates underlying the ability of acupuncturists to inflict a painful treatment for therapeutic benefit, without experiencing anxiety and personal distress, which might impair their ability to be of assistance. (Length of Acupuncture Training and Structural Plastic Brain Changes in Professional Acupuncturists. PLoS One. 2013 Jun 19;8(6):e66591).
Categories: Acupuncture research
