The Impact of Interictal Discharges on Performance
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Purpose of Review
Our purpose is to review evidence relating to the concept that interictal epileptiform discharges (IEDs) impair brain performance.
Sophisticated measures of motor and cognitive performance have clarified older observations, confirming that in both animals and humans, IEDs affect aspects of performance, IED morphology, frequency, anatomical distribution, and duration matter. However, we now know that it is difficult to draw a line between IEDs and seizures, not only by electrical criteria but even by metabolic and molecular measures.
IEDs impair performance acutely and probably chronically. Thus, there are good theoretical reasons for suppressing them, but no consensus has been reached on how much effort this deserves. Many antiepileptic medications effective for control of clinical seizures have little effect on IEDs. Better methods of measuring outcomes may allow selection of individual patients for whom treatment aimed at IEDs is worthwhile.
KeywordsEpilepsy Interictal discharges Performance Antiepileptic drugs EEG
Compliance with Ethical Standards
Conflict of Interest
Edward Faught reports grants and personal fees from UCB Pharma, personal fees from Eisai, grants from Brain Sentinel, personal fees from Biogen, grants from NINDS/University of Alabama at Birmingham, outside the submitted work. Ioannis Karakis declares no potential conflict of interest. Daniel L. Drane reports grants from Medtronic, Inc., personal fees from Neuropace, grants from NIH/NINDS, outside the submitted work.
Human and Animal Rights and Informed Consent
All reported studies/experiments with human or animal subjects performed by the authors have been previously published and complied with all applicable ethical standards (including the Helsinki declaration and its amendments, institutional/national research committee standards, and international/national/institutional guidelines).
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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