The role of touch in acupuncture treatment.

Acupuncture is a therapeutic treatment that is characterised by the insertion of a needle at a particular location on the body. Acupuncture stimulation includes sensory-discriminative and affective-social touch dimensions. In this review, we discuss the role of touch during acupuncture stimulation with an emphasis on the therapeutic, sensory-discriminative and affective-social aspects. In the discriminative dimension, de qi, which is associated with needling, includes a combination of various sensations, such as heaviness, numbness, soreness and distension. Achieving the appropriate de qi sensation appears to be fundamental to the therapeutic outcome following acupuncture treatment. In the affective dimension, the acupuncture procedure typically includes gentle manual touch stimulation, which induces feelings of calm and well-being, perhaps by activating C tactile fibres. Enhanced activity of C tactile afferents may induce a 'limbic touch' response, resulting in emotional and hormonal reactions. Because acupuncture is a 'therapist intensive' and complex intervention, it is necessary to understand the role of social touch between the practitioner and patient. Both sensory-discriminative and affective-social touch aspects play an important role in the therapeutic effect of acupuncture treatment in clinical practice.