Following electrical stimulation of the DRG, what change is observed in membrane excitability?

The correct choice indicates that following electrical stimulation of the dorsal root ganglion (DRG), there is a decrease in membrane excitability. This decrease occurs due to the activation of ion channels and pathways that can lead to hyperpolarization of the neuronal membrane. When the DRG, which houses the cell bodies of sensory neurons, is subjected to electrical stimulation, it can lead to a temporary adjustment in the neuronal firing threshold.

Typically, after stimulation, the neurophysiological response may include a refractory period wherein the membrane potential becomes less responsive to subsequent stimuli. During this time, the influx of potassium ions can cause hyperpolarization, making it harder for the neuron to generate action potentials. This phenomenon reflects a change in the overall excitability of the neuronal membrane, highlighting how stimulation can alter the capacity of neurons to respond to additional inputs.

In understanding this, it's also recognized that while other options such as fluctuation or no change might seem plausible in certain contexts, they do not accurately reflect the clear physiological response associated with DRG stimulation, where a decrease in excitability is more pronounced and paralleled by underlying biological processes.