A shift in the membrane potential to a value that is more negative than the resting membrane potential is referred to as a(n) .

A shift in the membrane potential to a value that is more negative than the resting membrane potential is referred to as hyperpolarization.

Here are the steps that explain this process:

1. Resting Membrane Potential: In a resting neuron, the inside of the neuron is negative relative to the outside. This is due to the distribution of ions on either side of the membrane and the selective permeability of the membrane to different ions. This state is known as the resting membrane potential.

2. Stimulus: When a neuron is stimulated, channels in the neuron's membrane open to allow positive ions to flow into the neuron.

3. Hyperpolarization: If the stimulus is inhibitory, the neuron's membrane potential becomes more negative (it 'hyperpolarizes'), moving further from the threshold needed to trigger an action potential. This makes the neuron less likely to fire an action potential.

4. Return to Resting Potential: After the stimulus ends, the neuron returns to its resting membrane potential.

So, in summary, a shift in the membrane potential to a value that is more negative than the resting membrane potential is referred to as hyperpolarization. This is a mechanism that inhibits the neuron from firing an action potential.