IMR Press / JIN / Volume 18 / Issue 1 / DOI: 10.31083/j.jin.2019.01.18
Open Access Original Research
High-frequency stimulation of afferent axons alters firing rhythms of downstream neurons
Show Less
1 Key Laboratory of Biomedical Engineering of Education Ministry, College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, Zhejiang 310027, China
*Correspondence: (Zhouyan Feng)
J. Integr. Neurosci. 2019, 18(1), 33–41;
Submitted: 23 January 2018 | Accepted: 28 March 2019 | Published: 30 March 2019
Copyright: © 2019 Ma et al. Published by IMR press.
This is an open access article under the CC BY-NC 4.0 license (

Deep brain stimulation is an emerging treatment for brain disorders. However, the mechanisms of high-frequency brain stimulation are unclear. Recent studies have suggested that high-frequency stimulation might produce therapeutic effects by eliminating pathological rhythms in neuronal firing. To test the hypothesis, the present study investigated whether stimulation of axonal afferent fibers might alter firing rhythms of downstream neurons in in-vivo experiments with Sprague-Dawley rats. Stimulation trains of 100 Hz with one minute duration were applied to the Schaffer collaterals of hippocampus Area CA1 in anaesthetized rats. Spikes of single interneurons and pyramidal neurons in the downstream region were analyzed. The spike rhythms before, during, and after the stimulations were evaluated by analyzing the power spectrum density of autocorrelograms of the spiking sequences. The rhythms of local field potentials were also evaluated by power spectrum density. During baseline recordings, theta rhythms were obvious in the spiking sequences of both types of neuron and in the local field potentials of the stratum radiatum. However, these theta rhythms were all suppressed significantly during the stimulations. Additionally, the results of Pearson's correlation analysis showed that 20-30% variation in the theta rhythms of neuronal firing could be explained by changes of the theta rhythms in local field potentials. High-frequency axonal stimulation might prevent the original rhythmic excitation in afferent fibers and generate new excitation by stimulation pulses per se, thereby suppressing the theta rhythms of individual neuron firing and of local field potentials in the region downstream from stimulation. The results provide new evidence to support the hypothesis that high-frequency stimulation can alter the firing rhythms of neurons, which may underlie the therapeutic effects of deep brain stimulation.

Deep brain stimulation
high frequency stimulation
unit spike
theta rhythm
local field potential
power spectrum density
axonal block
hippocampus area CA1
Figure 1.
Back to top