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in this effort, we report a low power Flash FPGA based control system for benefiting closed-loop neuroscience experiments. A digital implementation of closed-loop proportional-integral-derivative control algorithm has been implemented for offering more flexibility to generate further optogenetic stimulation to stabilize the epileptiform oscillation in epileptiform neuron network. The proposed digital control system receiving recordings from an implantable probe, preformed the closed-loop control algorithm and generating optogenetic stimulation to control epileptic seizures as a closed-loop system. The prototype is capable of satisfying the real time constraints posed by the application when clocked at 20 MHz which costs 4.67 rnA.

Epilepsy is a dynamic disorder of the brain at the system level which is due to abnormal activity of the brain cells. A closed-loop control system is designed in this work to detect the epileptic seizures and hence to suppress it through stimulating the brain cells. Proportional-Integral-Derivative (PID) is the most extensively used closed loop controller because of its simple implementation and robust performance. Although some efforts have been done to use PID controller to suppress the abnormal brain activities, the previously proposed systems were limited for specific cases or model parameters due to the stability constraints. This work is proposing to use the fractional order PID which is the generalization of the traditional PID system to suppress the epileptic seizures. By using the fractional PID, different stability domains are created based on the fractional orders and hence more degree of freedom for the system parameters. In this work, the Neural Mass Model (NMM) is used as a test platform for the controller for suppressing the brain activity. A graphical technique for stability contours is illustrated in this work to make the parameters determination easy for different stability conditions. MATLAB simulations are conducted to verify the controller performance, and the simulation results show the ability of the controller to suppress the focal epilepsy seizures at different scenarios.

This paper presents a design and implementation of an ultrasonic wireless energy transfer link to a visual cortical prosthesis implant device. Two ultrasonic transducers with 2 mm thickness and 12 mm diameter are implemented from scratch using Pz27 disc shape. The power transfer ultrasound link is demonstrated using 2 mm of tissue mimic in-vitro. The target voltage, required to operate the implant, of 1.8 V, 3.3 V and 5 V is achieved. The ultrasonic link and the overall system efficiencies are found to be 14.99% and 25% respectively. This system is found to be working in 36% of the FDA limit (720 mW/cm2).