ArticleProceedings of the National Academy of Sciences of the United States of America2015
Classical conditioning of analgesic and hyperalgesic pain responses without conscious awareness.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 64 papers, 1 of them a synthesis that pooled it.
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Who cites it
64 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Pooled it
- Domain-General Neural Effects of Associative Learning and Expectations on Pain and Hedonic Taste Perception.The Journal of neuroscience : the official journal of the Society for Neuroscience · 2026Trial
- The impact of pharmaceutical form and simulated side effects in an open-label-placebo RCT for improving psychological distress in highly stressed students.Scientific reports · 2023Trial
- The pain alarm response - an example of how conscious awareness shapes pain perception.Scientific reports · 2019Trial
- Trial
- Effects of subtle cognitive manipulations on placebo analgesia - An implicit priming study.European journal of pain (London, England) · 2017Trial
- Classical conditioning without verbal suggestions elicits placebo analgesia and nocebo hyperalgesia.PloS one · 2017Trial
- Shadow-Induced Forgetting in a Game-Based Paradigm on Nonclinical Adults and Its Effects on Consciousness, Emotional Valence, and Temporal Dynamics: Crossover Study.JMIR serious games · 2025Article
- Nocebo effects are stronger and more persistent than placebo effects in healthy individuals.eLife · 2025Article
- Working with patients' treatment expectations - what we can learn from homeopathy.Frontiers in psychology · 2024Review
- The Placebo Effect in Psychosis: Why It Matters and How to Measure It.Biological psychiatry global open science · 2023Review
- How Instructions, Learning, and Expectations Shape Pain and Neurobiological Responses.Annual review of neuroscience · 2023Review
- Classical conditioning of faciliatory paired-pulse TMS.Scientific reports · 2023Article
- Inducing forgetting of unwanted memories through subliminal reactivation.Nature communications · 2022Article
- The Consciousness of Pain: A Thalamocortical Perspective.NeuroSci · 2022Article
- Classically conditioned modulation of pain depends on stimulus intensity.Experimental brain research · 2022Article
- Placebo and nocebo effects in youth: subjective thermal discomfort can be modulated by a conditioning paradigm utilizing mental states of low and high self-efficacy.British journal of pain · 2022Article
- When one suffers less, all suffer less: Individual pain ratings are more effective than group ratings in producing placebo hypoalgesia.European journal of pain (London, England) · 2022Article
- Expectations: How and when do they contribute to placebo analgesia?Frontiers in psychiatry · 2022Article
- Associative learning and extinction of conditioned threat predictors across sensory modalities.Communications biology · 2021Article
4 more citing papers are in PubMed but not listed here.
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Authors and funding
5 authors.
Funding
Abstract
Pain reduction and enhancement can be produced by means of conditioning procedures, yet the role of awareness during the acquisition stage of classical conditioning is unknown. We used psychophysical measures to establish whether conditioned analgesic and hyperalgesic responses could be acquired by unseen (subliminally presented) stimuli. A 2 × 2 factorial design, including subliminal/supraliminal exposures of conditioning stimuli (CS) during acquisition/extinction, was used. Results showed significant analgesic and hyperalgesic responses (P < 0.001), and responses were independent of CS awareness, as subliminal/supraliminal cues during acquisition/extinction led to comparable outcomes. The effect was significantly larger for hyperalgesic than analgesic responses (P < 0.001). Results demonstrate that conscious awareness of the CS is not required during either acquisition or extinction of conditioned analgesia or hyperalgesia. Our results support the notion that nonconscious stimuli have a pervasive effect on human brain function and behavior and may affect learning of complex cognitive processes such as psychologically mediated analgesic and hyperalgesic responses.
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