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irradiation
irradiation In this historical usage, irradiation means a spreading of nervous stimulation beyond its usual pathway, so that excitement from one sense organ can activate other parts of the nervous system not directly linked with it.
In this historical usage, irradiation means a spreading of nervous stimulation beyond its usual pathway, so that excitement from one sense organ can activate other parts of the nervous system not directly linked with it. The source notes that this diffusion might occur peripherally or in the spinal cord, especially with strong stimulation or when the system is already in a state of readiness.