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Updated: Aug 10, 2026
04:59
Cheek Injection Model for Simultaneous Measurement of Pain and Itch-related Behaviors
Published on: September 27, 2019
Urge to scratch represented in the human cerebral cortex during itch
J C Hsieh1, O Hägermark, M Ståhle-Bäckdahl
1Department of Clinical Neuroscience, Karolinska Institute/Hospital, Stockholm, Sweden.
Journal of Neurophysiology
|December 1, 1994
Summary
This study reveals the brain
Area of Science:
- Neuroscience
- Psychology
Background:
- The sensory and motor aspects of itch perception and the urge to scratch are not fully understood.
- Investigating the neural correlates of itch processing is crucial for understanding related conditions.
Purpose of the Study:
- To investigate the central nervous system processing of itch.
- To identify brain regions involved in the urge to scratch.
Main Methods:
- Functional positron emission tomography (PET) was used to measure regional cerebral blood flow (rCBF) in 10 healthy volunteers.
- Intracutaneous histamine injections were administered to induce itch.
Main Results:
- A central representation of the urge to scratch was identified.
- Coactivation of the anterior cingulate cortex (ACC), supplementary motor area (SMA), premotor area (PM), and inferior parietal lobule (IPL) was observed.
- The posterior ACC (Brodmann 24) is linked to the sensory and affective components of itch.
Conclusions:
- The study elucidates the neural basis of the itch-scratch cycle.
- Motor preparation areas (SMA, PM, IPL) are involved in the urge to scratch.
- The ACC plays a role in the subjective experience of itch.
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