Can we infer subthalamic nucleus spike trains from intranuclear local field potentials?

The subthalamic nucleus (STN) is one of the subcortical nuclei that constitute the basal ganglia and a pivotal point of their function and dysfunction. In this paper, we use intranuclear recordings, acquired intraoperatively during deep brain stimulation procedure, to investigate whether it is possible to infer STN spike trains using only the underlying local field potentials (LFPs). We regard the LFPs to be the input and the spikes to be the output of a simple Hammerstein-Wiener model and we show that STN spikes can indeed be inferred from intranuclear LFPs, at least with moderate success. Our model, although not always reliable when predicting exact spike positions, shows a good accuracy in predicting the up to 1 kHz structure in STN spike trains. Hence, intranuclear LFPs can indeed hold useful information for predicting STN spiking activity.