acupuncture & brain imaging

Advances in functional neuroimaging techniques have made it possible to study both the neuroanatomical and neurophysiological responses associated with acupuncture. An impressive body of literature has identified a distributed network of brain activity that is evoked by stimulation with acupuncture needles and is subject to considerable modulation by a variety of stimulus parameters, contextual factors and clinical conditions. Several studies have documented that stimulation of various acupuncture points elicits overlapping brain responses in a number of cortical and subcortical brain regions, including activation in the sensorimotor cortical network (the insula, thalamus, anterior cingulate cortex and primary and secondary somatosensory cortices) and deactivation in the limbic-paralimbic-neocortical network (the medial prefrontal cortex, caudate, amygdala, posterior cingulate cortex and parahippocampus). These distributed brain areas are closely associated with a wider pain matrix that is responsible for modulating both the sensation of pain and affective pain perception.             

A meta-analysis of functional MRI (fMRI) studies revealed common activation patterns in the sensorimotor cortical network and deactivation patterns in the limbic-paralimbic-neocortical network following acupuncture needle stimulation. The brain haemodynamic responses to acupuncture stimulation reflect sensory-discriminative and also cognitive and affective dimensions of pain.