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<b>Abstract</b>This research examines the placebo effect on intuitive guessing within forced-choice tasks, specifically using the Zener cards test and a sound stimulus as the placebo inducer.Results from 100 naive participants demonstrated that the 'Placebo' condition achieved significantly higher correct response rates than expected by chance, with 22.3% success rate vs. 20.0% (binomial test = 2.85, <i>p</i>-value approximately 0.005, Cohen’s h = 0.056).Control group analyses, which included 50 participants, ruled out the possibility that these results were due to a learning effect from the order of experimental conditions.Analysis using a GLMM for binary data explored the role of experimental conditions and other variables on participant performance. The model included factors such as condition ('No-Placebo', 'Placebo', 'First Control Session', and 'Second Control Session'), participant self-reported confidence scores and reaction times, as well as reaction times in Zener card guessing tests. Among the experimental conditions, through fixed effects analysis, only the 'Placebo' one showed a significant effect (Estimate = 0.2048, <i>p</i> = 0.0184) with an increased likelihood of success (odds ratio = 1.227), suggesting that participants in this condition were more likely to correctly identify the Zener cards compared to the control condition.The limitations of the research are addressed in the discussion section.<b>Keywords</b>: placebo; guessing, intuition; Zener Cards; forced-choice