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Single neurons may encode simultaneous stimuli by switching between activity patterns.

ABSTRACT: How the brain preserves information about multiple simultaneous items is poorly understood. We report that single neurons can represent multiple stimuli by interleaving signals across time. We record single units in an auditory region, the inferior colliculus, while monkeys localize 1 or 2 simultaneous sounds. During dual-sound trials, we find that some neurons fluctuate between firing rates observed for each single sound, either on a whole-trial or on a sub-trial timescale. These fluctuations are correlated in pairs of neurons, can be predicted by the state of local field potentials prior to sound onset, and, in one monkey, can predict which sound will be reported first. We find corroborating evidence of fluctuating activity patterns in a separate dataset involving responses of inferotemporal cortex neurons to multiple visual stimuli. Alternation between activity patterns corresponding to each of multiple items may therefore be a general strategy to enhance the brain processing capacity, potentially linking such disparate phenomena as variable neural firing, neural oscillations, and limits in attentional/memory capacity.

SUBMITTER: Caruso VC

PROVIDER: S-EPMC6045601 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Single neurons may encode simultaneous stimuli by switching between activity patterns.

Caruso Valeria C VC Mohl Jeff T JT Glynn Christopher C Lee Jungah J Willett Shawn M SM Zaman Azeem A Ebihara Akinori F AF Estrada Rolando R Freiwald Winrich A WA Tokdar Surya T ST Groh Jennifer M JM

Nature communications 20180713 1

How the brain preserves information about multiple simultaneous items is poorly understood. We report that single neurons can represent multiple stimuli by interleaving signals across time. We record single units in an auditory region, the inferior colliculus, while monkeys localize 1 or 2 simultaneous sounds. During dual-sound trials, we find that some neurons fluctuate between firing rates observed for each single sound, either on a whole-trial or on a sub-trial timescale. These fluctuations a ...[more]

PMID: 30006598

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Single neurons may encode simultaneous stimuli by switching between activity patterns.

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Single neurons may encode simultaneous stimuli by switching between activity patterns.

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