Bryan Chen
Notebook

NotebookEntry 04

Light Into Spike

A 12-second mechanism-of-action study. A virus delivers the gene for a light-gated channel, blue light opens it, and the neuron fires.

  • Motion graphic
  • 12 seconds
  • 1080p
  • Made with Claude
  • 26 September 2026
Fig. 1Twelve seconds at 30 frames a second, rendered straight from the code, on a loop. About 6 MB.
Open the live player

Scrub the timeline, slow it to a quarter speed, or step one frame at a time.

The mechanism

Optogenetics in four beats. An AAV capsid carries the gene for channelrhodopsin-2 (ChR2) into a neuron. About two to three weeks later the cell has built ChR2 channels into its membrane. A pulse of 470 nm blue light opens them, positive ions, mostly sodium, rush in, and the membrane crosses threshold into an action potential.

How it was made

Claude drew every frame in code on an HTML canvas, with no video editor and no 3D software. The video above is a straight render of those frames, and the live player runs the same code in your browser, film grain and all.