Longitudinal Single Neuron Electrophysiology in the Mouse Visual Cortex using Microwire Brush Arrays

Author(s): Alireza Saeedi, Kun Wang, Nikos K. Logothetis, Masataka Watanabe.

Long-term stable single-unit recording in the brain is essential to the longitudinal study of brain functions. Microwire brush arrays (MBA) compliant with brain tissue are excellent tools for long-term stable neural recordings. However, there are multiple challenges in applying these electrodes to small animals (e.g., mice). Here, we resolve several challenges of using MBA probes in the mouse. By integrating microwire electrodes and ultra-light microdrives, we performed long-term electrophysiology and tracked the same neuronal population in the mouse visual cortex over two months. Moreover, we found that the orientation-tuning properties of visual neurons remain unchanged and used the visual response fingerprint of the neurons to track them over days of recording. Furthermore, we propose the use of Nonclassical Multidimensional Scaling (MDS) for inferring microwires' spatial organization in the brain and demonstrate its successful use in spatiotemporal template matching algorithms for spike sorting.