In vivo voltage-sensitive dye imaging of mouse visual cortex activity evoked by intracortical electrical stimulation

Cortical gamma oscillations have been implicated in a variety of cognitive, behavioral, and circuit-level phenomena. However, the circuit mechanisms of gamma-band generation and synchronization across cortical space remain uncertain. Using optogenetic patterned illumination in acute brain slices of mouse visual cortex, we define a circuit composed of layer 2/3 (L2/3) pyramidal cells and somatostatin (SOM) interneurons that phase-locks ensembles across the retinotopic map. The network oscillations generated here emerge from non-periodic stimuli, and are stimulus size-dependent, coherent across cortical space, narrow band (30 Hz), and depend on SOM neuron but not parvalbumin (PV) neuron activity; similar to visually induced gamma oscillations observed in vivo. Gamma oscillations generated in separate cortical locations exhibited high coherence as far apart as 850 μm, and lateral gamma entrainment depended on SOM neuron activity. These data identify a circuit that is sufficient to mediate long-range gamma-band coherence in the primary visual cortex.

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Neuronal signaling patterns in the developing mouse visual cortex in vivo

Neuroscience Research ◽

10.1016/j.neures.2007.06.012 ◽

2007 ◽

Vol 58 ◽

pp. S3

Author(s):

Arthur Konnerth

Keyword(s):

Visual Cortex ◽

Neuronal Signaling ◽

Mouse Visual Cortex

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Synaptic circuit restoration and functional recovery in the mouse visual cortex after ischemic injury and direct in vivo reprogramming of astrocytes into neurons

The FASEB Journal ◽

10.1096/fasebj.2020.34.s1.05621 ◽

2020 ◽

Vol 34 (S1) ◽

pp. 1-1

Author(s):

Alexander Chubykin ◽

Yu Tang ◽

Qiuyu Wu ◽

Esther Ryu ◽

Zifei Pei ◽

...

Keyword(s):

Visual Cortex ◽

Functional Recovery ◽

Ischemic Injury ◽

Mouse Visual Cortex ◽

Synaptic Circuit

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Sensory-driven and spontaneous gamma oscillations engage distinct cortical circuitry

Journal of Neurophysiology ◽

10.1152/jn.00137.2015 ◽

2016 ◽

Vol 115 (4) ◽

pp. 1821-1835 ◽

Cited By ~ 16

Author(s):

Cristin G. Welle ◽

Diego Contreras

Keyword(s):

Visual Cortex ◽

Visual Stimulation ◽

Oscillation Amplitude ◽

Gamma Oscillations ◽

Gamma Oscillation ◽

Inhibitory Neurons ◽

Sensory Representation ◽

Cortical Circuitry ◽

Mouse Visual Cortex

Gamma oscillations are a robust component of sensory responses but are also part of the background spontaneous activity of the brain. To determine whether the properties of gamma oscillations in cortex are specific to their mechanism of generation, we compared in mouse visual cortex in vivo the laminar geometry and single-neuron rhythmicity of oscillations produced during sensory representation with those occurring spontaneously in the absence of stimulation. In mouse visual cortex under anesthesia (isoflurane and xylazine), visual stimulation triggered oscillations mainly between 20 and 50 Hz, which, because of their similar functional significance to gamma oscillations in higher mammals, we define here as gamma range. Sensory representation in visual cortex specifically increased gamma oscillation amplitude in the supragranular (L2/3) and granular (L4) layers and strongly entrained putative excitatory and inhibitory neurons in infragranular layers, while spontaneous gamma oscillations were distributed evenly through the cortical depth and primarily entrained putative inhibitory neurons in the infragranular (L5/6) cortical layers. The difference in laminar distribution of gamma oscillations during the two different conditions may result from differences in the source of excitatory input to the cortex. In addition, modulation of superficial gamma oscillation amplitude did not result in a corresponding change in deep-layer oscillations, suggesting that superficial and deep layers of cortex may utilize independent but related networks for gamma generation. These results demonstrate that stimulus-driven gamma oscillations engage cortical circuitry in a manner distinct from spontaneous oscillations and suggest multiple networks for the generation of gamma oscillations in cortex.

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