💊 Peripheral Nerve Sodium Channel Signaling — 3D

The 2D original steps through five discrete stages of the nociceptor pain pathway on a flat canvas: a stimulus opens stimulus-gated channels at the free nerve ending, producing a graded generator potential computed as -70 + stimulus% * 0.62 mV; if that potential reaches the -55 mV threshold, voltage-gated sodium channels (Nav1.7/1.8) fire a regenerative action potential that propagates down the axon at a fiber-dependent speed — 15 m/s for myelinated, saltatory-conducting A-delta fibers, or 1.2 m/s for unmyelinated, continuously-conducting C-fibers. This 3D companion keeps that exact formula and both real conduction speeds, and renders the whole pathway as a genuine orbitable Three.js scene: a branching nerve terminal with channel-tipped branches that glow and release ion particles proportional to stimulus, a threshold ring and Nav-channel cluster at the trigger zone, a true 3D axon — segmented myelin sheaths with flashing nodes of Ranvier for A-delta, or a continuous translucent Schwann sheath for C-fiber — and a traveling action-potential sphere that crosses the real distance at the real relative speed before bursting at a dorsal-horn synapse. A new Channel Blockade slider layers in a real non-opioid analgesic mechanism: raising it lifts the effective firing threshold (-55 + blockade% * 0.3 mV), modeling how local anesthetics that block Nav1.7/1.8 prevent pain signals from ever reaching threshold, rather than dulling the signal after it arrives centrally.