An implantable microsystem for studying the Parkinson's Disease

The Pakinson's Disease (PD) is one of the most common diseases for the elderly, and is attributed to the degeneration of neurons in the brain. This paper presents a microsystem suitable for recording the neural activity relating to the PD symptons for a long term, as well as for stimulating the neurons in the deep brain. As many studies indicate that changes of low-frequency field potentials correlate with the PD symptoms, eight chopper amplifiers with tunable bandwidth are designed to record not only low-frequency potentials but also neuronal spikes. Two stimulation circuits with adjustable stimulation voltage are also incorporated to investigate how neural activities change with the stimulation condition. Moreover, the microsystem contains wireless modules for both power and data transmission, facilitating long-term implantation. The functionality of microsystem is tested and discussed in this paper.