Abstract
Responses of auditory cortex neurons are modulated by spectral or temporal context, but much less is known about modulation by spatial context. Here, we investigated single neuron responses to sequences of sounds either repeatedly delivered from a single spatial location or randomly delivered from multiple spatial locations in the auditory cortex of awake marmosets. Instead of inducing adaptation as expected from well-documented stimulus-specific adaptation studies, repetitive stimulation from a target speaker evoked long-lasting, location-specific facilitation (LSF) in many neurons, irrespective of the visibility of the target speaker. The extent of LSF decreased with decreasing presentation probability of the target speaker. Intracellular recordings showed that repetitive sound stimulation evoked sustained membrane potential depolarization which gave rise to firing rate facilitation. Computational models suggest two distinct neural mechanisms underlying LSF. Our findings revealed a novel form of contextual modulation in the auditory cortex that may play a role in auditory stream segregation.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
↵+ Co-first author