This week on Journal Club session Shavika Rastogi will talk about her master thesis entitled "Prediction of Electrode Position inside rat brain using Neuromorphic Hardware".
Neural probes with large number of close packed recording sites each comprising of 32 electrodes are being developed for large scale neuronal recordings from multiple brain areas simultaneously to understand complex brain activity in vivo. By precisely mapping the position of each site inside rat brain, they help us to characterize neural activity on the basis of cortical depth from where it is obtained. Their application lies in neurosurgery, where it is important to locate the target of surgical interest inside the brain in real time. In this work, we have first compared various methods from literature to analyze extracellular activity recorded using CMOS neural probes from different cortical depths and from different locations along same lateral axis of rat brain to find a criterion on the basis of which recordings can be classified. After finding out the most promising criterion, we have tried to implement it on neuromorphic hardware SpiNNaker. We tested single neuron and spiking excitatory-inhibitory network for implementation and found that excitatory-inhibitory network is more robust to noise present in signal and its output can be improved by introducing lateral inhibition. Our results show that SpiNNaker can be used for rough indication of cortical depth.