Ripples Have Distinct Spectral Properties and Phase-Amplitude Coupling With Slow Waves, but Indistinct Unit Firing, in Human Epileptogenic Hippocampus

Frontiers in Neurology

Jerome Engel¹  Yuval Nir²  Diego Slezak³  Tomás Pastore³  Mei Leng⁴  Inkyung Song⁶  Zachary Waldman⁶  Mustafa Donmez⁶  Michael R. Sperling⁶  Shennan A. Weiss⁶  Anatol Bragin⁷  Richard Staba⁷  Iren Orosz⁷  Richard Gorniak⁸  Itzhak Fried⁹  Ashwini Sharan^1,10  Chengyuan Wu^1,10 

[1] 0Brain Research Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States;1Department of Physiology and Pharmacology, Sackler School of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv-Yafo, Israel;Department of Computer Science, University of Buenos Aires, Buenos Aires, Argentina;Department of Medicine, Statistics Core, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States;Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States;Department of Neurology and Neuroscience, Thomas Jefferson University, Philadelphia, PA, United States;Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States;Department of Neuroradiology, Thomas Jefferson University, Philadelphia, PA, United States;Department of Neurosurgery, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States;Department of Neurosurgery, Thomas Jefferson University, Philadelphia, PA, United States;Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA, Los Angeles, CA, United States;

关键词: sleep;    high-frequency oscillation;    slow wave;    epilepsy;    hippocampus;    ripple;   

DOI  :  10.3389/fneur.2020.00174

来源: DOAJ

【 摘 要 】

Ripple oscillations (80–200 Hz) in the normal hippocampus are involved in memory consolidation during rest and sleep. In the epileptic brain, increased ripple and fast ripple (200–600 Hz) rates serve as a biomarker of epileptogenic brain. We report that both ripples and fast ripples exhibit a preferred phase angle of coupling with the trough-peak (or On-Off) state transition of the sleep slow wave in the hippocampal seizure onset zone (SOZ). Ripples on slow waves in the hippocampal SOZ also had a lower power, greater spectral frequency, and shorter duration than those in the non-SOZ. Slow waves in the mesial temporal lobe modulated the baseline firing rate of excitatory neurons, but did not significantly influence the increased firing rate associated with ripples. In summary, pathological ripples and fast ripples occur preferentially during the On-Off state transition of the slow wave in the epileptogenic hippocampus, and ripples do not require the increased recruitment of excitatory neurons.

【 授权许可】

Unknown