What does the term 'potential' refer to in the context of neurons?

In the context of neurons, the term 'potential' primarily refers to the charge difference within neurons, which is a fundamental aspect of their function. This charge difference, known as the membrane potential, exists because of the distribution of ions, such as sodium and potassium, across the neuronal membrane. The resting potential, which is typically around -70 mV, indicates that the inside of the neuron is negatively charged compared to the outside.

When a neuron receives a stimulus, this charge difference can change, leading to depolarization and, if the threshold is reached, an action potential. This process is essential for the propagation of nerve impulses. Understanding the membrane potential is crucial for comprehending how neurons communicate and react to stimuli in the nervous system.

Other aspects—like the capacity for an impulse to travel or the response time to stimuli—are outcomes of the potential but do not define what 'potential' itself means in a physiological sense. The energy requirement for action potentials is also a separate concept that focuses on the metabolic aspects of neuronal activity rather than the electrochemical state of the neuron, which is encapsulated in the concept of membrane potential.