Related Experiment Video
Updated: Apr 6, 2026
Acute Mouse Brain Slicing to Investigate Spontaneous Hippocampal Network Activity
Published on: August 28, 2020
Impact of cognitive stimulation on ripples within human epileptic and non-epileptic hippocampus
Milan Brázdil1,2, Jan Cimbálník3, Robert Roman4,5
1Behavioural and Social Neuroscience Research Group, CEITEC-Central European Institute of Technology, Masaryk University, Brno, Czech Republic. mbrazd@med.muni.cz.
Background:
Until now there has been no way of distinguishing between physiological and epileptic hippocampal ripples in intracranial recordings. In the present study we addressed this by investigating the effect of cognitive stimulation on interictal high frequency oscillations in the ripple range (80-250 Hz) within epileptic (EH) and non-epileptic hippocampus (NH).
Methods:
We analyzed depth EEG recordings in 10 patients with intractable epilepsy, in whom hippocampal activity was recorded initially during quiet wakefulness and subsequently during a simple cognitive task. Using automated detection of ripples based on amplitude of the power envelope, we analyzed ripple rate (RR) in the cognitive and resting period, within EH and NH.
Results:
Compared to quiet wakefulness we observed a significant reduction of RR during cognitive stimulation in EH, while it remained statistically marginal in NH. Further, we investigated the direct impact of cognitive stimuli on ripples (i.e. immediately post-stimulus), which showed a transient statistically significant suppression of ripples in the first second after stimuli onset in NH only.
Conclusion:
Our results point to a differential reactivity of ripples within EH and NH to cognitive stimulation.
More Related Videos
07:03Evaluation of Hemisphere Lateralization with Bilateral Local Field Potential Recording in Secondary Motor Cortex of Mice
Published on: July 31, 2019
06:22A Pilot Study on the Repetitive Transcranial Magnetic Stimulation of Aβ and Tau Levels in Rhesus Monkey Cerebrospinal Fluid
Published on: September 3, 2021
