Back to U19 Main Page

Sensation - coding, sensation, behavior. John Maunsell. Readout and control of spatiotemporal neuronal codes for behavior

Title: Sound encoding of neurons in input and associative layers of auditory cortex

Abstract:

Scientific Topic: Sound encoding of neurons in input and associative layers of auditory cortex

Data Types: 2-photon calcium imaging (GCaMP6s) in L2/3 and L4 of auditory cortex in awake head-fixed mice 3.

Open Questions: How is sound information encoded after stimulus offset? How is sound reliably encoded when trial-to-trial variability is so prevalent in these neuronal responses? What are the differences in population encoding from L4 to L2/3 of auditory cortex? The primary auditory cortex processes acoustic sequences for the perception of behaviorally meaningful sounds such as speech. Sound information arrives at its input layer 4 from where activity propagates to associative layer 2/3. It is currently not known whether there is a characteristic organization of neuronal population activity across layers and sound levels during sound processing. Here, we identify neuronal avalanches, which in theory and experiments have been shown to maximize dynamic range and optimize information transfer within and across networks, in primary auditory cortex. We used in vivo 2-photon imaging of pyramidal neurons in cortical layers L4 and L2/3 of mouse A1 to characterize the populations of neurons that were active spontaneously, i.e. in the absence of a sound stimulus, and those recruited by single-frequency tonal stimuli at different sound levels. This dataset allows for the calculation of robust receptive fields for each neuron and observation of the moment-to-moment activity of hundreds of neurons in two distinct areas of the auditory cortical circuit (L4 and L2/3). This dataset facilitates theorists to explore the differences in population encoding from L4 to L2/3 of auditory cortex, how sound information is encoded over time, and how sound is reliably encoded in the presence of overt trial-to-trial variability in responses.

Prior analysis: https://www.frontiersin.org/articles/10.3389/fnsys.2019.00045/full -- paper relies entirely on this dataset https://www.nature.com/articles/s41598-020-67819-4 -- paper uses the transgenic portion of the dataset as the C57BL/6 group

Back to U19 Main Page