Subjective Analgesic Effects of Naloxone and Virtual Reality
Status:
Unknown status
Trial end date:
2014-06-01
Target enrollment:
Participant gender:
Summary
This study is designed to test a specific hypothesis exploring the neurophysiologic
mechanism(s) that underlie the pain- relieving effects of immersive Virtual Reality (VR) as a
non-pharmacologic pain management technique, using healthy volunteers experiencing carefully
controlled thermal and/or electrical pain in the laboratory. Over the past decade, our
research group has performed a series of NIH-funded investigations of VR analgesia - in both
the clinical pain and laboratory pain settings - demonstrating its clinical efficacy and
safety. In the current study we will test pharmacologic manipulation of VR analgesia (with
the opioid analgesia antagonist naloxone). We anticipate that this theoretical work will
provide a foundation for future clinical applications of immersive VR - whether used alone or
in combination with other analgesic agents - and make immersive VR a more effective and more
widely used analgesic tool for the treatment of clinical pain.
Our previous work with immersive VR indicates that its use during a painful event can reduce
subjective pain reports during both acute clinical and laboratory pain by 20-50% [1].
Furthermore, we have shown that effective VR analgesia is associated with reduced
pain-related brain activity that is quantitatively and qualitatively comparable to clinically
relevant doses of systemic opioid analgesics [2]. The laboratory pain protocol proposed in
the current application is identical to the UW HSD-approved protocol used in our previous
studies (#25296 - "Reducing Brief Thermal and Electrical Pain"). What is specifically
different in the current protocol is the use of naloxone to determine whether VR analgesia
operates through an endogenous opioid-dependent mechanism or not. The results of this study
will not only suggest the mechanism of action of VR analgesia, but also allow us to more
effectively apply immersive VR analgesia in the clinically pain setting through its
thoughtful combination with well-established pharmacologic analgesic techniques, such as
opioid analgesia administration.
The specific aim of this study and the hypothesis it tests are as follows: To determine the
extent to which subjective analgesic effects of VR analgesia are inhibited by opioid receptor
antagonism with naloxone. Hypothesis - VR analgesia will not be inhibited by systemic opioid
receptor antagonism, suggesting that VR analgesia is not mediated by release of endogenous
opiates and/or by activation of opioid-dependent descending central nervous system pathways.