Which type of nerves are primarily depolarized first by an electrical current under normal conditions?

Superficial, large diameter nerves are primarily depolarized first by an electrical current under normal conditions due to their unique properties. Large diameter nerves have a larger cross-sectional area, which decreases the internal resistance to electrical flow and increases their capacitance. This allows them to respond more quickly and effectively to the depolarizing current.

In addition, superficial nerves are located closer to the surface of the skin, where electrical stimuli can more easily penetrate. Their large size also means they have a higher threshold for activation and are more likely to reach the necessary action potential in response to the current. This rapid depolarization of large diameter nerves contributes to the speed and efficiency of signal transmission, particularly in sensory and motor pathways.

Understanding this principle is crucial for application in athletic training and rehabilitation settings, where electrical modalities may be used for pain management, muscle stimulation, or enhancing recovery by targeting the appropriate nerve types for optimal response.