715: Multisensory Integration in chronic low-back pain

Topic: Experimental (Non-clinical) Human Studies
Subtopic: Pain Category (ICD-11), Chronic primary musculoskeletal pain, Developing methodology/technology, Assessment and Measurement of Pain/Nociception, Pain mechanisms (e.g. descending inhibitory control, placebo, inflammation)

Background and Aims: Multisensory integration (MI) enhances perceptual reliability by combining information across sensory modalities and plays a fundamental role in everyday perception. Growing evidence indicates that MI is altered in certain chronic pain conditions, such as migraine and fibromyalgia. However, it remains unclear whether these alterations reflect a general characteristic of chronic pain or are specific to conditions in which non-nociceptive sensory processing is also affected. The present study examined pain-related MI in healthy individuals and in patients with chronic low back pain (cLBP), serving as an example of a chronic pain condition with prominent peripheral contributions and comparatively less central involvement.

Methods: 30 healthy participants and 30 patients with cLBP (>3 months) completed two MI tasks: a pain-induced flash illusion (PIFI) paradigm and a reaction time (RT) task including bimodal visual, auditory, and nociceptive stimuli. Stimuli were applied to the arm or lower back in counterbalanced order. Reaction time data were analyzed using mathematical and computational modeling, including race model analysis.

Results: Both groups showed faster responses to bimodal than unimodal stimuli (p<.001), reflecting robust redundant signals effects, with no group differences. Race model analysis revealed significant violations across all stimulus combinations and stimulation sites in both groups (all p<.001), indicating bimodal stimuli were processed more efficiently than predicted by independent race models. Group comparisons confirmed no significant differences in race model violation (all p>.24). In the PIFI task, both groups reported fewer visual flashes when paired with painful stimulation (p<.001), again with no group differences regardless whether the stimulation site was in the affected or non-affected area.

Conclusions: These findings indicate preserved multisensory integration in cLBP. Healthy participants and patients showed comparable RT facilitation, race model violation, and susceptibility to pain-induced illusion. Notably, pain integrated with visual and auditory signals in a manner comparable to other sensory modalities, suggesting that MI mechanisms for nociceptive input are preserved. These results indicate that MI alterations are condition-specific rather than a universal feature of chronic pain.

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Presenting Author: Dr. Einav Gozansky
Submitting Author: Einav Gozansky

Senior Author: PD. Dr Jan Mehnert

IASP 2026 Global Year theme of Neuropathic Pain: No

• Anna Katharina Meyer: Medical student - Institute for Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
• Jan Mehnert: PD. Dr. - Institute for Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany,