State-space model for estimating acupuncture spike firing rate

In order to reveal the underlying mechanisms about the conduction of acupuncture signal, manual acupuncture (MA) manipulations with different frequencies are taken at `Zusanli´ points of experimental rats. The induced spike series in spinal cord dorsal horn is detected and recorded. Consider spike series as point process, it is found that rate coding features of acupuncture with different frequencies are different. To elucidate the underlying mechanisms, we develop a state-space model for estimating the spike firing rate function by maximum likelihood using an approximate Expectation-Maximization (EM) algorithm. Model goodness-of-fit assessment, confidence intervals for the spike firing rate function are also given. It is shown that this model could accurately characterize acupuncture spike firing rate. The underlying mechanisms of acupuncture are better understood from the perspective of state-space by combining the simulation results.