%A Sakata,Shuzo %A Harris,Kenneth %D 2012 %J Frontiers in Neural Circuits %C %F %G English %K sensory cortex,cell-type,cortical circuit,ensemble recording,slow oscillation %Q %R 10.3389/fncir.2012.00109 %W %L %M %P %7 %8 2012-December-21 %9 Original Research %+ Dr Shuzo Sakata,University of Strathclyde,Strathclyde Institute of Pharmacy and Biomedical Sciences,161 Cathedral Street,Glasgow,G4 0RE,United Kingdom,shuzo.sakata@strath.ac.uk %+ Prof Kenneth Harris,Imperial College,Department of Bioengineering, Electrical and Electronic Engineering,London,SW7 2AZ,United Kingdom,kenneth.harris@imperial.ac.uk %# %! Brain states in auditory cortex %* %< %T Laminar-dependent effects of cortical state on auditory cortical spontaneous activity %U https://www.frontiersin.org/articles/10.3389/fncir.2012.00109 %V 6 %0 JOURNAL ARTICLE %@ 1662-5110 %X Cortical circuits spontaneously generate coordinated activity even in the absence of external inputs. The character of this activity depends on cortical state. We investigated how state affects the organization of spontaneous activity across layers of rat auditory cortex in vivo, using juxtacellular recording of morphologically identified neurons and large-scale electrophysiological recordings. Superficial pyramidal cells (PCs) and putative fast-spiking interneurons (FSs) were consistently suppressed during cortical desynchronization. PCs in deep layers showed heterogeneous responses to desynchronization, with some cells showing increased rates, typically large tufted PCs of high baseline firing rate, but not FSs. Consistent results were found between desynchronization occurring spontaneously in unanesthetized animals, and desynchronization evoked by electrical stimulation of the pedunculopontine tegmental (PPT) nucleus under urethane anesthesia. We hypothesize that reduction in superficial layer firing may enhance the brain's extraction of behaviorally relevant signals from noisy brain activity.