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Updated: Feb 19, 2026
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Cheek Injection Model for Simultaneous Measurement of Pain and Itch-related Behaviors
Published on: September 27, 2019
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Nocebo-induced modulation of cerebral itch processing - An fMRI study
Missanga F van de Sand1, Mareike M Menz1, Christian Sprenger1
1Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
Neuroimage
|November 7, 2017
Summary
The brain
Area of Science:
- Neuroscience
- Psychology
- Dermatology
Background:
- Itch sensation is significantly influenced by psychological expectations.
- Previous studies show sensory and behavioral changes due to itch-related stimuli.
Purpose of the Study:
- Investigate the neural mechanisms of the itch-related nocebo effect.
- Understand how expectations modulate itch perception.
Main Methods:
- Used functional magnetic resonance imaging (fMRI) in healthy subjects.
- Induced itch via histamine and thermal modulation.
- Applied a nocebo condition by falsely instructing participants about "transcutaneous electrical nerve stimulation" (TENS) increasing itch.
Main Results:
- Participants reported significantly stronger itch in the nocebo condition compared to control.
- fMRI revealed increased activity in the rolandic operculum during the nocebo effect.
- Enhanced functional coupling between the insula and periaqueductal gray (PAG) was observed in the nocebo condition.
Conclusions:
- The rolandic operculum may integrate expectation with somatosensory information.
- Top-down modulation of itch involves cortex-PAG interactions, potentially shared with pain pathways.
- Expectations play a crucial role in modulating itch perception through specific neural pathways.
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