Abstract
In the neuroscience and physiology fields, studies on implantable neural signal detection and transmission systems have clarified the relationship between motor and sensory activities and neural activity. This technique is applicable to handicapped persons in areas of brain-computer interface (BCI) and bionic arm. In this study, we developed a multi-channel neural signal recording system that is capable of measuring neural signals steadily even when the signal amplitude decreases and the noise level increases during long-term measurement. In a previous study, we developed and tested a multi-channel system that simultaneously detected spikes, and calculated the firing frequency. The system comprises a neural signal enhancer with non-linear circuitry and a spike detector. We demonstrated that the performance of the system was sufficient to be used as an embedded spike detector. However, there was an issue that power consumption of the circuit was not optimized. In this study, we reduced the power consumption of the system and evaluated its performance for long term measurements in a rat. The test results with the improved hardware showed that the new system consumes substantially less power than the previous system. The experiments of long-term spike measurement showed that stable spike measurements were possible using a neural signal enhancer with non-linear circuitry.
