• E N van den Broeke, N Geene, C M van Rijn, O H G Wilder-Smith, and J Oosterman.
• Donders Institute for Brain, Cognition, and Behaviour, Radboud University Nijmegen, The Netherlands.
• Eur J Pain. 2014 Jan 1;18(1):86-91.

BackgroundHigh-frequency electrical stimulation (HFS) of human skin induces not only an increased pain sensitivity in the conditioning area but also an increased pain sensitivity to mechanical punctate stimuli in the non-conditioned surrounding skin area. The aim of the present study was to investigate whether this heterotopically increased mechanical pain sensitivity can be facilitated through the induction of negative expectations.MethodsIn two independent conditions [a nocebo (n = 15) and control condition (n = 15)], we applied mechanical pain stimuli before, directly after, 10 min and 20 min after HFS in the skin area surrounding the conditioning area, and measured the reported pain intensity [visual analogue scale (VAS)]. All subjects (of both conditions) received a written instruction about the HFS protocol, but only the instruction in the nocebo condition was extended by the following text (in Dutch): 'After the HFS, your skin will become more sensitive to the pinprick stimulation'.ResultsOur results clearly show that induced expectations of increased mechanical pain sensitivity after HFS facilitates the reported pain intensity after HFS more than when no information is given.ConclusionsThis study shows for the first time that brain mechanisms, via the induction of negative expectations, can facilitate heterotopic mechanical hyperalgesia after HFS of human skin.© 2013 European Pain Federation - EFIC®

21 keywords...

hide…