GRACE · hiGh-Resolution imAging of the barrel CortEx through VSD and LFP recordings

hiGh-Resolution imAging of the barrel CortEx through VSD and LFP recordings

The aim of this project (EU funded, Horizon 2020 Framework Programme, Project #796177 — GRACE) is to develop an innovative and advanced dual approach to study the barrel cortex, combining two-photon imaging and high-resolution electrical recording, in order to investigate in depth the spatiotemporal dynamics of whisker-evoked cortical activity in anaesthetised and awake head-restrained mouse. The barrel cortex in rodents is part of the primary somatosensory cortex and a well-known example of topographic mapping, where each whisker on the snout of the animal is mapped onto a specific cortical area, called a barrel. Thanks to its unique functional organisation, this system offers excellent conditions to investigate neural mechanisms at the base of sensory coding, processing, and plasticity. Sensory-evoked activity in the barrel cortex is known to manifest as propagating waves but up to now there are no studies directed towards a high-resolution mapping of these waves in the barrel cortex in vivo. Thanks to the chronic cranial window designed and patented by prof. Kuhn at OIST, Voltage Sensitive Dye and Calcium imaging will be performed simultaneously with Local Field Potentials (LFP) recordings through high-resolution implantable neural probes for the first time. Once fully established, this multimodal technique will allow the study of neuronal signal propagation through a 3D architecture in living tissue with simultaneous high-resolution optical and electrical recordings. This action will promote a close collaboration and a two-way transfer of scientific knowledge between Padova (UNIPD) and Okinawa (OIST), enhancing the scientific relations between the European Research Area and Japan. This project will also contribute to the design and development of advanced neuroprostheses which will allow a bidirectional communication with brain microcircuits through high-resolution LFP recordings and patterned electrical stimulation of neural populations. Moreover, the results of this research will have a strong impact on basic neuroscience of population coding, providing novel insights on the propagation of sensory information within the barrel cortex and offering a new advanced technique to study the brain in the upcoming research projects. A methodological paper about the new technique and the first results are published in Frontiers in Neuroscience – Brain Imaging Methods with the title "Simultaneous two-photon voltage or calcium imaging and multi-channel LFP recordings in barrel cortex of awake and anesthetized mice" (Authors: C. Cecchetto*, S. Vassanelli, B. Kuhn*, http://doi.org/10.3389/fnins.2021.741279, Associated data are available on Dryad at https://doi.org/10.5061/dryad.dbrv15f23).

Data: CORDIS, © European Union