What is the term for a brief electrical charge that travels down the axon of a neuron?

The term for a brief electrical charge that travels down the axon of a neuron is known as an action potential. This mechanism is fundamental to the functioning of neurons, as it is the process through which they communicate and transmit signals. An action potential occurs when a neuron reaches a certain threshold, causing a rapid change in electrical potential across the cell membrane. This involves the opening of voltage-gated ion channels, allowing sodium ions to rush into the cell, followed by potassium ions exiting, thus propagating the electrical signal along the axon.

The reasons for selecting "action potential" over the other options are rooted in the definitions and roles these terms play in neuroscience. A neuronal impulse and synaptic transmission refer to broader concepts concerning the transmission of signals in a network of neurons, where the former can describe the action potential but does not specifically define the electrical charge traveling down the axon. Synaptic transmission focuses on the communication between neurons at synapses, where neurotransmitters are released rather than the actual electrical charge down the axon. Resting potential refers to the state of a neuron when it is not actively firing, characterized by a stable, negative internal charge relative to the outside; thus, it is not the active process of signal conduction.