Author Interviews, Dermatology, Johns Hopkins, Pain Research / 24.02.2017
Leaky Gate Model Connects Intense Itch With Pain
MedicalResearch.com Interview with:
Xinzhong Dong PhD
The Solomon H. Snyder Department of Neuroscience and Center for Sensory Biology
Howard Hughes Medical Institute
Johns Hopkins University School of Medicine
Baltimore, MD 21205
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: It is a puzzle that troubles the field for many years that how pain and itch, two closely related sensations (once thought as one sensation), are differentiated by the nervous systems. Coding of pain and itch are heatedly debated for decades. The current specificity theory suggests that these two kinds of signals are carried by separate pathways, with some interactions, for example pain can inhibit itch and that explains why we all scratch to inhibit pain. It is true in the periphery (our previous study indicate a small population of neurons in the periphery only codes for itch sensation), but now our study suggests that there could be more crosstalk between these two sensations in the central than we expected.
People might not notice in real life, but in human psychophysical studies, well-isolated experimental environments, when human subjects are given itchy substances, they typically report intense itch sensations accompanied by minor noxious sensations, such as pricking, stinging and burning. Our new leaky gate model suggest in certain circumstances intense itch signals can trigger minor pain sensations, which can explain such phenomenon.
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