This is one of the first broad-audience articles I've seen that actually acknowledges neuronal firing rates as an important practical consideration. Usually it

This is one of the first broad-audience articles I've seen that actually acknowledges neuronal firing rates as an important practical consideration. Usually it's simplified in explanations as "binary", on or off. This isn't wrong for any instant in time (and is sometimes good enough for conceptual models), but in reality the firing rate varies as a function of the stimulus. Analog, if you like...