A researcher wishes to determine under what circumstances, or in response to what input, a particular neuron fires. A technique well suited to this purpose is

single-cell recording.

Explanation:

single cell recording is a technique used in research to observe changes in neurons such as changes in voltage or current in a neuron. It works by inserting a microelectrode into the skull of the animal being observed. The microelectrode is inserted into the neuron that is observed, which measures the charge in the neuron and observes any changes while manipulating any inputs to see results

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