ArticleReduction of fear of movement-related pain and pain-related anxiety: An associative learning approach using a voluntary movement paradigmMeulders, Anna,*; Vlaeyen, Johan W.S.a,bAuthor Information Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article. aResearch Group on Health Psychology, Department of Psychology, University of Leuven, Leuven, Belgium bDepartment of Clinical Psychological Science, Maastricht University, The Netherlands *Corresponding author. Address: Department of Psychology, University of Leuven, Tiensestraat 102, Box 3726, 3000 Leuven, Belgium. Tel.: +32 (0)16 32 60 38; fax: +32 (0)16 32 61 44. E-mail address:[email protected] Article history: Received 5 January 2012; Received in revised form 15 March 2012; Accepted 12 April 2012. Pain: July 2012 - Volume 153 - Issue 7 - p 1504-1513 doi: 10.1016/j.pain.2012.04.013 Buy Metrics Abstract Summary Pain-related fear and anxiety can be reduced by a Pavlovian extinction procedure. Reducing pain-related anxiety promotes safety (inhibitory) learning about movements never associated with pain. The fear-avoidance model advances fear of pain as a key factor in the origins of chronic pain disability. Initial evidence in those with chronic back pain reveals that exposure therapy reduces fear levels, disability, and pain. Despite the success of exposure in the clinic, fundamental research about its underlying mechanisms lags behind. Using a conditioning paradigm with movements as conditioned stimuli (CS) and a painful shock as unconditioned stimuli (US), we investigated the extinction of experimental fear of movement-related pain and pain-related anxiety (respectively induced by predictable and unpredictable pain). Dependent measures were self-reported fear and eyeblink startle. During acquisition, all groups received both predictable and unpredictable training. In the predictable context, one movement (CS+) was consistently followed by the shock-US, but another movement was not (CS−). In the unpredictable context, joystick movements never signaled the shock-US; shock-US were delivered during the intertrial interval (ITI). During extinction, the extinction group continued training in the predictable context but the CS+ movement was no longer reinforced; the context exposure group continued training in the unpredictable context but ITI shock-US were omitted. The control group continued training after the acquisition reinforcement scheme. Results revealed that fear ratings for the CS+ were extinguished in the extinction group but not in the control group. Interestingly, omitting the ITI shocks not only reduced ITI startle responses in the context exposure group compared with the control group, but also reduced the fear ratings and startle responses elicited by the unpredictable CS. The clinical implications of these findings are discussed. © 2012 Lippincott Williams & Wilkins, Inc.