A Closed-Loop Optogenetic Platform

Abstract

Neuromodulation is an established treatment for numerous neurological conditions, but to expand the therapeutic scope there is a need to improve the spatial, temporal and cell-type specificity of stimulation. Optogenetics is a promising area of current research, enabling optical stimulation of genetically-defined cell types without interfering with concurrent electrical recording for closed-loop control of neural activity. We are developing an open-source system to provide a platform for closed-loop optogenetic neuromodulation, incorporating custom integrated circuitry for recording and stimulation, real-time closed-loop algorithms running on a microcontroller and experimental control via a PC interface. We include commercial components to validate performance, with the ultimate aim of translating this approach to humans. In the meantime our system is flexible and expandable for use in a variety of preclinical neuroscientific applications. The platform consists of a Controlling Abnormal Network Dynamics using Optogenetics (CANDO) Control System (CS) that interfaces with up to four CANDO headstages responsible for electrical recording and optical stimulation through custom CANDO LED optrodes. Control of the hardware, inbuilt algorithms and data acquisition is enabled via the CANDO GUI (Graphical User Interface). Here we describe the design and implementation of this system, and demonstrate how it can be used to modulate neuronal oscillations in vitro and in vivo.

A deep learning-based automated closed-loop optogenetic system for neuromodulation during seizures

“…We propose a flexible and modular design of a closed-loop optogenetics system with a deep neural net for seizure detection. Conventional state-of-the-art systems for closed-loop optogenetics have limitations related to flexibility, scalability, and feature-detection algorithms 16 .…”

“…This stereotypical model is widely used in electrical and computer engineering fields, such as oscillator design, adaptive filtering, and machine learning [12][13][14][15] . In neuroscience, closedloop systems are real-time instantaneous feedback types 2,16 or input adaptation types [17][18][19] . Problems such as seizure interruption fall into the first type.…”

New imaging instrument in animal models: Two‐photon miniature microscope and large field of view miniature microscope for freely behaving animals

“…Closed‐loop systems can be used for detecting and suppressing the development of epileptiform activity (Sorokin et al, 2017) and delineating the cellular mechanisms when performing effective deep‐brain stimulation, paving the way for brain‐computer interfaces. When combined with optogenetics, closed‐loop systems have the potential for the real‐time decoding of neural patterns and conduct closed‐loop optogenetic intervention accordingly in freely behaving animals (Armstrong et al, 2013; Firfilionis et al, 2021; Grosenick et al, 2015; Kathe et al, 2021; Srinivasan et al, 2018).…”