Hours of high-frequency stimulations reveal intracellular neuronal trends in vivo

¹ Gonda Multidisciplinary Brain Research Center, and the Goodman Faculty of Life Sciences, Bar-Ilan University 52900 Ramat Gan, Israel
² Department of Physics, Bar-Ilan University - 52900 Ramat Gan, Israel
³ MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital Charlestown, MA 02119, USA

^(b) Ido.kanter@biu.ac.il

Received: 20 September 2016
Accepted: 7 December 2016

Abstract

The neuronal response to controlled stimulations in vivo has been classically estimated using a limited number of events. Here we show that hours of high-frequency stimulations and recordings of neurons in vivo reveal previously unknown response phases of neurons in the intact brain. Results indicate that for stimulation frequencies below a critical neuronal characteristic frequency, f_c, response timings are stabilized to tens-of-microseconds accuracy. For stimulation frequencies exceeding f_c the firing frequency is saturated and independent of the stimulation frequency, as a result of random neuronal response failures. This neuronal plasticity, previously shown in vitro, supports a robust mechanism for low firing rates on a network level.