Can Expectations Change Pain?

Can what we expect actually influence what we experience? Everyday life provides numerous examples suggesting that it can. Walking toward a familiar staircase and expecting one more step than is actually there, reaching to lift a box you believe is heavy only to discover it is empty, or stepping onto what appears to be solid ground only to find an unexpected surface all illustrate the brain's reliance on prediction. In each case, the nervous system generates expectations before sensory information has been fully processed. Pain appears to function in a remarkably similar way. Rather than processing sensory information in isolation, the nervous system continually integrates expectations, previous experiences, context, and incoming sensory information before generating conscious experience.

Expectations arise from internal predictive models continuously generated by the nervous system. These models are shaped by prior experience, learning, environmental context, and physiological state.¹ When incoming sensory information aligns with expectations, perception tends to proceed efficiently. When substantial prediction errors occur, the nervous system updates its internal models accordingly.² Pain is no exception. Experimental studies demonstrate that expectations can influence pain perception through descending modulatory systems involving cortical, brainstem, and spinal mechanisms.³ These findings support the concept that expectations participate in nervous system processing without implying that pain lacks a biological foundation.

Büchel et al. (2014)³ demonstrated that expectations substantially influence pain perception through identifiable neural mechanisms using a predictive coding framework. Their work showed that the brain continuously integrates prior expectations with incoming sensory information when constructing the experience of pain. Atlas and Wager (2012)⁴ further demonstrated that placebo and nocebo effects are associated with measurable changes in activity within the insula, anterior cingulate cortex, thalamus, and prefrontal cortex, providing strong evidence that expectations exert biological effects through distributed neural networks rather than simple psychological suggestion. ScienceDirect Together, these studies provide an important neuroscientific foundation for understanding how expectations influence pain perception.

Atlas (2023) reviewed converging evidence demonstrating that verbal instructions, learning, and expectations influence subjective pain through parallel neural circuits involving both pain-related regions and broader networks responsible for affect, learning, and cognitive control. The review emphasizes that expectations shape pain through identifiable neurobiological mechanisms rather than through imagination or suggestion alone. Annual Reviews Building on earlier work in predictive processing, contemporary evidence supports the concept that expectations interact continuously with sensory input, attention, prior learning, and contextual information before conscious pain perception emerges. This growing body of research provides a biological framework for understanding placebo and nocebo effects while reinforcing that pain remains a genuine physiological experience influenced by multiple interacting sources of information. Annual Reviews

Understanding the influence of expectations does not diminish the reality of pain. Rather, it expands our understanding of the biological processes contributing to perception. Expectations represent one source of information among many that the nervous system continually integrates while determining the most adaptive response. This perspective helps explain why identical injuries or medical procedures may be experienced differently by different individuals while remaining entirely consistent with modern neuroscience. Importantly, this understanding does not suggest that expectations alone determine pain. Pain emerges through the integration of sensory information with previous experiences, physiological state, emotional context, environmental factors, and cognitive processes. Expectations therefore represent one important component of a much larger adaptive system.