Abstract
Recent experimental studies show cortical circuit responses to external stimuli display varied dynamical properties. These include stimulus strength-dependent population response patterns, a shift from synchronous to asynchronous states and a decline in neural variability. To elucidate the mechanisms underlying these response properties and explore how they are mechanistically related, we develop a neural circuit model that incorporates two essential features widely observed in the cerebral cortex. The first feature is a balance between excitatory and inhibitory inputs to individual neurons; the second feature is distance-dependent connectivity. We show that applying a weak external stimulus to the model evokes a wave pattern propagating along lateral connections, but a strong external stimulus triggers a localized pattern; these stimulus strength-dependent population response patterns are quantitatively comparable with those measured in experimental studies. We identify network mechanisms underlying this population response, and demonstrate that the dynamics of population-level response patterns can explain a range of prominent features in neural responses, including changes to the dynamics of neurons' membrane potentials and synaptic inputs that characterize the shift of cortical states, and the stimulus-evoked decline in neuron response variability. Our study provides a unified population activity pattern-based view of diverse cortical response properties, thus shedding new insights into cortical processing.
Highlights
Understanding how cortical circuits respond to sensory stimulation is of fundamental importance in elucidating the mechanisms of cortical processing [1]
Recent whole-cell recordings have revealed that sensory stimulation can shift cortical neurons from synchronous to asynchronous states, as characterized by the dynamics of membrane potentials [3,4]
We address the fundamental problems regarding the intrinsic network mechanism underlying stimulus strength-dependent response patterns [5], the shift from the synchronous to the asynchronous state [3,4], and the decline in neural variability caused by sensory stimuli [2]
Summary
Understanding how cortical circuits respond to sensory stimulation is of fundamental importance in elucidating the mechanisms of cortical processing [1]. Recent whole-cell recordings have revealed that sensory stimulation can shift cortical neurons from synchronous to asynchronous states, as characterized by the dynamics of membrane potentials [3,4]. Unrelated to these response properties measured at the level of individual neurons, it has been found that there exist distinct spatio-temporal patterns in neural population response activity, depending on the strength of feed-forward thalamic input signals [5]. To deepen our understanding of cortical processing, it is important to unravel the mechanistic links between these response properties of cortical circuits across different levels, and account for them in a unified way
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.