Format

Send to

Choose Destination
Clin Neurophysiol. 2019 Jul 19. pii: S1388-2457(19)31150-2. doi: 10.1016/j.clinph.2019.07.007. [Epub ahead of print]

Cognitive effort decreases beta, alpha, and theta coherence and ends afterdischarges in human brain.

Author information

1
Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. Electronic address: rl@jhmi.edu.
2
Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
3
Department of Public Health Sciences, University of California, Davis, School of Medicine, Davis, CA 95616, USA; Kaiser Permanente Washington Health Research Institute, Seattle, WA 98101, USA.
4
Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.

Abstract

OBJECTIVE:

Mental activation has been reported to modify the occurrence of epileptiform activity. We studied its effect on afterdischarges.

METHOD:

In 15 patients with implanted electrodes we presented cognitive tasks when afterdischarges occurred. We developed a wavelet cross-coherence function to analyze the electrocorticography before and after the tasks and compared findings when cognitive tasks did or did not result in afterdischarge termination. Six patients returned for functional MRI (fMRI) testing, using similar tasks.

RESULTS:

Cognitive tasks often could terminate afterdischarges when direct abortive stimulation could not. Wavelet cross-coherence analysis showed that, when afterdischarges stopped, there was decreased coherence throughout the brain in the 7.13-22.53 Hz frequency ranges (p values 0.008-0.034). This occurred a) regardless of whether an area activated on fMRI and b) regardless of whether there were afterdischarges in the area.

CONCLUSIONS:

It is known that cognitive tasks can alter localized or network synchronization. Our results show that they can change activity throughout the brain. These changes in turn can terminate localized epileptiform activity.

SIGNIFICANCE:

Cognitive tasks result in diffuse brain changes that can modify focal brain activity. Combined with a seizure detection device, cognitive activation might provide a non-invasive method of terminating or modifying seizures.

KEYWORDS:

Afterdischarges; Attention; Cognition; Coherence; Effort

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center