Brain-to-brain communication channel

Viewed through information theory, a BBI is a noisy communication channel with three stages: encode a message from the sender's neural activity (decode an intention into symbols), transmit it over a digital link, and write it into the receiver as a detectable neural event. The end-to-end capacity is bounded by the worst of the three — sender decoding accuracy, transmission (usually lossless and not the bottleneck), and the fidelity with which the receiver can read the written stimulus.

Because both the read and the write ends are crude, the effective capacity is very low — the message set is typically binary (go/no-go, rotate or hold) and error rates are non-trivial — so demonstrations use redundancy, slow signaling, and pre-shared codebooks. Treating a BBI as a channel makes the design levers explicit: raise sender signal-to-noise ratio, choose a discriminable write percept, and add error-correcting structure rather than hoping for higher raw bandwidth.