Untuned But Not Irrelevant: A Role For Untuned Neurons In Sensory Information Coding

In the sensory systems, most neurons9 firing rates are tuned to at least one aspect of the stimulus. Other neurons are untuned, meaning that their firing rates appear not to depend on the stimulus. Previous work on information coding in neural populations has ignored the untuned neurons, based on the tacit assumption that they are unimportant. Recently, me and other researchers have begun to question that assumption. Using theoretical calculations and analyses of iin vivo neural data, I show how untuned neurons contribute to neural information coding. Ignoring untuned neurons can lead to severe underestimates of the amount of stimulus information encoded, and in some cases population codes can be made more informative by replacing tuned neurons with untuned ones.