"If ... a set of generalist neurons could be programmed to express signal transduction machinery that normally is present only in specialized sensory cells, these neurons also might acquire the capacity to respond selectively to the adequate physical or chemical triggers. Not only could all members of a population of neurons then be addressed simultaneously, susceptibility to stimulation rather than the stimulus itself would be localized, and even diffusely broadcast stimuli could elicit precise, patterned responses."
Zemelman, B.V., Nesnas, N., Lee, G.A., & Miesenbo, B. (2003) Photochemical gating of heterologous ion channels: Remote control over genetically designated
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