A/D and D/A encoder - neurons can encode both digital and analog information

Neural coding is a neuroscience related field concerned with characterizing the relationship between the stimulus and the individual or ensemble neuronal responses and the relationship among the electrical activity of the neurons in the ensemble.

Solving the Neural Code Conundrum: Digital or Analog?

Physicists have developed a technique that can tell which parts of the brain rely on analog signals and which rely on digital signals.