About this item:

614 Views | 610 Downloads

Author Notes:

Address Correspondence To: Daniel L. Drane, Ph.D., ABPP (CN), Associate Professor of Neurology and Pediatrics, Emory University School of Medicine, Woodruff Memorial Research Building, 101 Woodruff Circle, Suite 6111, Atlanta, Georgia, 30322, Email: ddrane@emory.edu

Author Disclosures: Dr. Gross receives consulting fees from Eli Lilly, Neuropace, St. Jude Medical Corp., Deep Brain Innovations, Visualase, Inc., Medtronic, and Duke University.

Dr. Loring reports receiving consulting fees from NeuroPace and Supernus and current grant support from PCORI and NIH; receives royalties from Oxford University Press; serves on the Professional Advisory Board for the Epilepsy Foundation, and sits on the editorial boards for Epilepsia, Epilepsy Research, and Neuropsychology Review.

He also receives funds related to neuropsychological assessment of patients with epilepsy including Wada testing.

Dr. Miller receives research funding from the NIH, CDC, Pfizer, UCB Pharma, and Sunovion.

He is on the editorial boards for Neurology® and Neurotherapeutics.

He is a shareholder and serves on the board of directors of Therma Neurosciences.

Dr. Ojemann receives funding from NIH, NSF and serves on the editorial boards of Neurosurgery and the Journal of Neurosurgery.

He bills for the performance of both laser ablation and resective surgery.

He is Chief Medical Officer for Therma Neuroscience, Inc.


Research Funding:

Dr. Drane’s research efforts are currently funded by two grants from the NIH/NINDS (K02 NS070960, & R01NS088748)

Dr. Kim receives salary support from a grant funded by the NIH/NINDS (R01NS088748).


  • Science & Technology
  • Life Sciences & Biomedicine
  • Behavioral Sciences
  • Clinical Neurology
  • Psychiatry
  • Neurosciences & Neurology
  • Interictal epileptiform discharges
  • Surgical outcome
  • Neuropsychological assessment

Interictal epileptiform discharge effects on neuropsychological assessment and epilepsy surgical planning


Journal Title:

Epilepsy and Behavior


Volume 56


, Pages 131-138

Type of Work:

Article | Post-print: After Peer Review


Both animal research and human research suggest that interictal epileptiform discharges (IEDs) may affect cognition, although the significance of such findings remains controversial. We review a wide range of literature with bearing on this topic and present relevant epilepsy surgery cases, which suggest that the effects of IEDs may be substantial and informative for surgical planning. In the first case, we present a patient with epilepsy with left anterior temporal lobe (TL) seizure onset who experienced frequent IEDs during preoperative neuropsychological assessment. Cognitive results strongly lateralized to the left TL. Because the patient failed performance validity tests and appeared amnestic for verbal materials inconsistent with his work history, selected neuropsychological tests were repeated 6 weeks later. Scores improved one to two standard deviations over the initial evaluation and because of this improvement, were only mildly suggestive of left TL impairment. The second case involves another patient with documented left TL epilepsy who experienced epileptiform activity while undergoing neurocognitive testing and simultaneous ambulatory EEG recording. This patient's verbal memory performance was impaired during the period that IEDs were present but near normal when such activity was absent. Overall, although the presence of IEDs may be helpful in confirming laterality of seizure onset, frequent IEDs might disrupt focal cognitive functions and distort accurate measurement of neuropsychological ability, interfering with accurate characterization of surgical risks and benefits. Such transient effects on daily performance may also contribute to significant functional compromise. We include a discussion of the manner in which IED effects during presurgical assessment can hinder individual patient presurgical planning as well as distort outcome research (e.g., IEDs occurring during presurgical assessment may lead to an underestimation of postoperative neuropsychological decline).

Copyright information:

© 2016 Elsevier Inc.

This is an Open Access work distributed under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/).
Export to EndNote