Background and aims. Classical conditioning and verbal suggestion can induce both placebo analgesia and nocebo hyperalgesia. The experiment aimed to investigate whether verbally provided suggestions incongruent with conditioning can abolish the effects of conditioning.
Methods. Participants were assigned to one of the four experimental groups: 1) placebo conditioning, 2) nocebo conditioning, 3) placebo conditioning followed by the suggestion of hyperalgesia, 4) nocebo conditioning followed by the suggestion of analgesia; or one of the three control groups. During the first phase of the experiment participants from experimental groups underwent a conditioning procedure. They received a series of pain stimuli preceded by one of two color stimuli. One of these colors preceded pain stimuli of moderate intensity and the other – pain stimuli of lower (in the placebo groups) or higher (in the nocebo groups) intensity. In the experimental groups 3 and 4, the conditioning procedure was followed by information about the association between colors and painful stimuli that was inconsistent with the conditioning applied. During the second phase of the experiment, participants in the experimental groups received a series of pain stimuli of moderate intensity preceded by color stimuli. Participants rated pain intensity and expectancy of pain intensity.
Results. Results of the study are presented on the poster.
Conclusions. In the clinical context patients frequently receive information concerning pain which could be contrary to what they experience. The results of this study add to the knowledge about the possible effects produced by suggestion incongruent with individual pain experiences.

CAN VERBAL SUGGESTION ABOLISH THE EFFECT OF CLASSICAL CONDITIONING ON PLACEBO ANALGESIA AND NOCEBO HYPERALGESIA?