Online Detection and Sorting of Single-Unit Recording Signal for Closed Loop Optogenetics Controlling

Electrical brain stimulation provides therapeutic benefits for patients with drug-resistant neurological disorders. But it has restricted access to cell-type selectivity. Optogenetics, in contrast, enables precise targeting of a specific cell type which can address the issue with electrical brain stimulation. Optogenetics is a light-based stimulation method, in which the target cells are transfected with light-sensitive ion channels called opsin. This technique can be used for both excitation and inhibition of cells based on light wavelength and opsin properties. To online modulation of neurons need a closed loop controlling. Closed-loop optogenetics system compares the neural signals with a predefined value at every moment and then decides what to do to achieve the desired value by optical stimulation [1]. One of the important brain signal recordings is single-unit recording (SUR) [2] whiles the most of signal processing method is offline. In this paper, an algorithm was proposed to online spike detection and sorting them based on wavelet transform which was programmed by Labview software. The algorithm consists of three main steps such as detecting spikes, extracting the features of every detected spike and assigning similar spikes to one group.