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Chartampila E, Elayouby KS, Leary P, LaFrancois JJ, Alcantara-Gonzalez D, Jain S, Gerencer K, Botterill JJ, Ginsberg SD, Scharfman HE. Choline supplementation in early life improves and low levels of choline can impair outcomes in a mouse model of Alzheimer's disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.05.12.540428. [PMID: 37214805 PMCID: PMC10197642 DOI: 10.1101/2023.05.12.540428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Maternal choline supplementation (MCS) improves cognition in Alzheimer's disease (AD) models. However, effects of MCS on neuronal hyperexcitability in AD are unknown. We investigated effects of MCS in a well-established mouse model of AD with hyperexcitability, the Tg2576 mouse. The most common type of hyperexcitability in Tg2576 mice are generalized EEG spikes (interictal spikes; IIS). IIS also are common in other mouse models and occur in AD patients. Im mouse models, hyperexcitability is also reflected by elevated expression of the transcription factor ΔFosB in the granule cells (GCs) of the dentate gyrus (DG), which are the principal cell type. Therefore we studied ΔFosB expression in GCs. We also studied the the neuronal marker NeuN within hilar neurons of the DG because other studies have reduced NeuN protein expression is a sign of oxidative stress or other pathology. This is potentially important because hilar neurons regulate GC excitability. Tg2576 breeding pairs received a diet with a relatively low, intermediate or high concentration of choline. After weaning, all mice received the intermediate diet. In offspring of mice fed the high choline diet, IIS frequency declined, GC ΔFosB expression was reduced, and NeuN expression was restored. Using the novel object location task, spatial memory improved. In contrast, offspring exposed to the relatively low choline diet had several adverse effects, such as increased mortality. They had the weakest hilar NeuN immunoreactivity and greatest GC ΔFosB protein expression. However, their IIS frequency was low, which was surprising. The results provide new evidence that a diet high in choline in early life can improve outcomes in a mouse model of AD, and relatively low choline can have mixed effects. This is the first study showing that dietary choline can regulate hyperexcitability, hilar neurons, ΔFosB and spatial memory in an animal model of AD.
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Affiliation(s)
- Elissavet Chartampila
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962
- Current address:Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC 27510
| | - Karim S. Elayouby
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962
- Current address: Department of Neurology, Mount Sinai School of Medicine, New York, NY 10029
| | - Paige Leary
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY 100016
| | - John J. LaFrancois
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962
- Department of Child and Adolescent Psychiatry , New York University Grossman School of Medicine, New York, NY 10016
| | - David Alcantara-Gonzalez
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962
- Department of Child and Adolescent Psychiatry , New York University Grossman School of Medicine, New York, NY 10016
| | - Swati Jain
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962
| | - Kasey Gerencer
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962
- Current address: Department of Psychology, University of Maine, Orono, ME 04469
| | - Justin J. Botterill
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962
- Current address: Department of Anatomy, Physiology, & Pharmacology, College of Medicine, Saskatoon, SK S7N 5E5
| | - Stephen D. Ginsberg
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY 100016
- Department of Psychiatry, New York University Grossman School of Medicine New York, NY 10016
- NYU Neuroscience Institute,, New York University Grossman School of Medicine, New York, NY 10016
| | - Helen E. Scharfman
- Center for Dementia Research, The Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962
- Department of Neuroscience and Physiology, New York University Grossman School of Medicine, New York, NY 100016
- Department of Child and Adolescent Psychiatry , New York University Grossman School of Medicine, New York, NY 10016
- Department of Psychiatry, New York University Grossman School of Medicine New York, NY 10016
- NYU Neuroscience Institute,, New York University Grossman School of Medicine, New York, NY 10016
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Meisenhelter S, Quon RJ, Steimel SA, Testorf ME, Camp EJ, Moein P, Culler GW, Gross RE, Lega BC, Sperling MR, Kahana MJ, Jobst BC. Interictal Epileptiform Discharges are Task Dependent and are Associated with Lasting Electrocorticographic Changes. Cereb Cortex Commun 2021; 2:tgab019. [PMID: 34296164 PMCID: PMC8152941 DOI: 10.1093/texcom/tgab019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 03/02/2021] [Accepted: 03/03/2021] [Indexed: 12/24/2022] Open
Abstract
The factors that control the occurrence of interictal epileptiform discharges (IEDs) are not well understood. We suspected that this phenomenon reflects an attention-dependent suppression of interictal epileptiform activity. We hypothesized that IEDs would occur less frequently when a subject viewed a task-relevant stimulus compared with viewing a blank screen. Furthermore, IEDs have been shown to impair memory when they occur in certain regions during the encoding or recall phases of a memory task. Although these discharges have a short duration, their impact on memory suggests that they have longer lasting electrophysiological effects. We found that IEDs were associated with an increase in low-frequency power and a change in the balance between low- and high-frequency oscillations for several seconds. We found that the occurrence of IEDs is modified by whether a subject is attending to a word displayed on screen or is observing a blank screen. In addition, we found that discharges in brain regions in every lobe impair memory. These findings elucidate the relationship between IEDs and memory impairment and reveal the task dependence of the occurrence of IEDs.
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Affiliation(s)
- Stephen Meisenhelter
- Department of Neurology, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03766, USA
- Department of Neurology, Geisel School of Medicine at Dartmouth College Hanover, NH 03755, United States
| | - Robert J Quon
- Department of Neurology, Geisel School of Medicine at Dartmouth College Hanover, NH 03755, United States
| | - Sarah A Steimel
- Department of Neurology, Geisel School of Medicine at Dartmouth College Hanover, NH 03755, United States
| | - Markus E Testorf
- Thayer School of Engineering at Dartmouth College, Hanover, NH 03755, United States
| | - Edward J Camp
- Department of Neurology, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03766, USA
| | - Payam Moein
- Department of Neurology, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03766, USA
| | - George W Culler
- Department of Neurology, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03766, USA
| | - Robert E Gross
- Department of Neurosurgery, Emory University, Atlanta, GA 30322, United States
| | - Bradley C Lega
- Department of Neurosurgery, University of Texas-Southwestern, Dallas, TX 75390, United States
| | - Michael R Sperling
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA 19144, United States
| | - Michael J Kahana
- Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104, United States
| | - Barbara C Jobst
- Department of Neurology, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03766, USA
- Department of Neurology, Geisel School of Medicine at Dartmouth College Hanover, NH 03755, United States
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Liu S, Parvizi J. Cognitive refractory state caused by spontaneous epileptic high-frequency oscillations in the human brain. Sci Transl Med 2020; 11:11/514/eaax7830. [PMID: 31619544 DOI: 10.1126/scitranslmed.aax7830] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 06/21/2019] [Accepted: 09/09/2019] [Indexed: 12/31/2022]
Abstract
Epileptic brain tissue is often considered physiologically dysfunctional, and the optimal treatment of many patients with uncontrollable seizures involves surgical removal of the epileptic tissue. However, it is unclear to what extent the epileptic tissue is capable of generating physiological responses to cognitive stimuli and how cognitive deficits ensuing surgical resections can be determined using state-of-the-art computational methods. To address these unknowns, we recruited six patients with nonlesional epilepsies and identified the epileptic focus in each patient with intracranial electrophysiological monitoring. We measured spontaneous epileptic activity in the form of high-frequency oscillations (HFOs), recorded stimulus-locked physiological responses in the form of physiological high-frequency broadband activity, and explored the interaction of the two as well as their behavioral correlates. Across all patients, we found abundant normal physiological responses to relevant cognitive stimuli in the epileptic sites. However, these physiological responses were more likely to be "seized" (delayed or missed) when spontaneous HFOs occurred about 850 to 1050 ms before, until about 150 to 250 ms after, the onset of relevant cognitive stimuli. Furthermore, spontaneous HFOs in medial temporal lobe affected the subjects' memory performance. Our findings suggest that nonlesional epileptic sites are capable of generating normal physiological responses and highlight a compelling mechanism for cognitive deficits in these patients. The results also offer clinicians a quantitative tool to differentiate pathological and physiological high-frequency activities in epileptic sites and to indirectly assess their possible cognitive reserve function and approximate the risk of resective surgery.
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Affiliation(s)
- Su Liu
- Laboratory of Behavioral and Cognitive Neuroscience, Department of Neurology and Neurological Sciences, Stanford University, CA 94305, USA
| | - Josef Parvizi
- Laboratory of Behavioral and Cognitive Neuroscience, Department of Neurology and Neurological Sciences, Stanford University, CA 94305, USA.
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Extent of Single-Neuron Activity Modulation by Hippocampal Interictal Discharges Predicts Declarative Memory Disruption in Humans. J Neurosci 2019; 40:682-693. [PMID: 31754015 PMCID: PMC6961998 DOI: 10.1523/jneurosci.1380-19.2019] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 10/17/2019] [Accepted: 11/17/2019] [Indexed: 11/21/2022] Open
Abstract
Memory deficits are common in epilepsy patients. In these patients, the interictal EEG commonly shows interictal epileptiform discharges (IEDs). While IEDs are associated with transient cognitive impairments, it remains poorly understood why this is. We investigated the effects of human (male and female) hippocampal IEDs on single-neuron activity during a memory task in patients with medically refractory epilepsy undergoing depth electrode monitoring. We quantified the effects of hippocampal IEDs on single-neuron activity and the impact of this modulation on subjectively declared memory strength. Across all recorded neurons, the activity of 50 of 728 neurons were significantly modulated by IEDs, with the strongest modulation in the medial temporal lobe (33 of 416) and in particular the right hippocampus (12 of 58). Putative inhibitory neurons, as identified by their extracellular signature, were more likely to be modulated by IEDs than putative excitatory neurons (19 of 157 vs 31 of 571). Behaviorally, the occurrence of hippocampal IEDs was accompanied by a disruption of recognition of familiar images only if they occurred up to 2 s before stimulus onset. In contrast, IEDs did not impair encoding or recognition of novel images, indicating high temporal and task specificity of the effects of IEDs. The degree of modulation of individual neurons by an IED correlated with the declared confidence of a retrieval trial, with higher firing rates indicative of reduced confidence. Together, these data link the transient modulation of individual neurons by IEDs to specific declarative memory deficits in specific cell types, thereby revealing a mechanism by which IEDs disrupt medial temporal lobe-dependent declarative memory retrieval processes. SIGNIFICANCE STATEMENT Interictal epileptiform discharges (IEDs) are thought to be a cause of memory deficits in chronic epilepsy patients, but the underlying mechanisms are not understood. Utilizing single-neuron recordings in epilepsy patients, we found that hippocampal IEDs transiently change firing of hippocampal neurons and disrupted selectively the retrieval, but not encoding, of declarative memories. The extent of the modulation of the individual firing of hippocampal neurons by an IED predicted the extent of reduction of subjective retrieval confidence. Together, these data reveal a specific kind of transient cognitive impairment caused by IEDs and link this impairment to the modulation of the activity of individual neurons. Understanding the mechanisms by which IEDs impact memory is critical for understanding memory impairments in epilepsy patients.
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Luz-Escamilla L, Morales-González JA. Association between Interictal Epileptiform Discharges and Autistic Spectrum Disorder. Brain Sci 2019; 9:brainsci9080185. [PMID: 31366163 PMCID: PMC6721430 DOI: 10.3390/brainsci9080185] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 07/28/2019] [Accepted: 07/30/2019] [Indexed: 02/07/2023] Open
Abstract
It has been reported that bioelectric alterations in an electroencephalogram (EEG) may play an etiological role in neurodevelopmental disorders. The clinical impact of interictal epileptiform discharges (IEDs) in association with autistic spectrum disorder (ASD) is unknown. The Autism Diagnostic Interview-Revised (ADI-R) is one of the gold standards for the diagnosis of autistic spectrum disorder. Some studies have indicated high comorbidity of IED and ASD, while other studies have not supported an association between the central symptoms of autism and IED. This review examines the high comorbidity and clinical impact of IED; patients with epilepsy are excluded from the scope of this review. ASD can be disabling and is diagnosed at an average age of 5 years old, at which point the greatest neurological development has occurred. If an association between IED and ASD is identified, a clinical tool that entails an innocuous procedure could enable diagnosis in the first years of life. However, in the absence of reports that prove an association between IED and ASD, patients should not be subjected to expensive treatments, such as the administration of anticonvulsant therapies.
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Affiliation(s)
- Laura Luz-Escamilla
- Laboratorio de Medicina de Conservación y Maestría en Ciencias de la Salud, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón S/N, Col. Casco de Santo Tomás, Alcaldía Miguel Hidalgo CP 11340, México.
- Departamento de Higiene Mental, Hospital General Centro Médico Nacional "La Raza", Instituto Mexicano del Seguro Social, Distrito Federal CP 02990, México.
| | - José Antonio Morales-González
- Laboratorio de Medicina de Conservación y Maestría en Ciencias de la Salud, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón S/N, Col. Casco de Santo Tomás, Alcaldía Miguel Hidalgo CP 11340, México.
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Kleen JK, Kirsch HE. The nociferous influence of interictal discharges on memory. Brain 2019; 140:2072-2074. [PMID: 28899025 DOI: 10.1093/brain/awx178] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Jonathan K Kleen
- Department of Neurology, University of California, San Francisco, California, USA
| | - Heidi E Kirsch
- Department of Neurology, University of California, San Francisco, California, USA
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Abstract
PURPOSE OF REVIEW Our purpose is to review evidence relating to the concept that interictal epileptiform discharges (IEDs) impair brain performance. RECENT FINDINGS 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.
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Affiliation(s)
- Edward Faught
- Emory University, Brain Health Center 292, 12 Executive Park Drive NE, Atlanta, GA, 30306, USA.
| | - Ioannis Karakis
- Emory University, Brain Health Center 292, 12 Executive Park Drive NE, Atlanta, GA, 30306, USA
| | - Daniel L Drane
- Emory University, Brain Health Center 292, 12 Executive Park Drive NE, Atlanta, GA, 30306, USA.,University of Washington, Seattle, WA, USA
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Ung H, Cazares C, Nanivadekar A, Kini L, Wagenaar J, Becker D, Krieger A, Lucas T, Litt B, Davis KA. Interictal epileptiform activity outside the seizure onset zone impacts cognition. Brain 2017; 140:2157-2168. [PMID: 28666338 DOI: 10.1093/brain/awx143] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 05/07/2017] [Indexed: 02/01/2023] Open
Abstract
See Kleen and Kirsch (doi:10.1093/awx178) for a scientific commentary on this article.Cognitive deficits are common among epilepsy patients. In these patients, interictal epileptiform discharges, also termed spikes, are seen routinely on electroencephalography and believed to be associated with transient cognitive impairments. In this study, we investigated the effect of spikes on memory encoding and retrieval, taking into account the spatial distribution of spikes in relation to the seizure onset zone as well as anatomical regions of the brain. Sixty-seven patients with medication refractory epilepsy undergoing continuous intracranial electroencephalography monitoring engaged in a delayed free recall task to test short-term memory. In this task, subjects were asked to memorize and recall lists of common nouns. We quantified the effect of each spike on the probability of successful recall using a generalized logistic mixed model. We found that in patients with left lateralized seizure onset zones, spikes outside the seizure onset zone impacted memory encoding, whereas those within the seizure onset zone did not. In addition, spikes in the left inferior temporal gyrus, middle temporal gyrus, superior temporal gyrus, and fusiform gyrus during memory encoding reduced odds of recall by as much as 15% per spike. Spikes also reduced the odds of word retrieval, an effect that was stronger with spikes outside of the seizure onset zone. These results suggest that seizure onset regions are dysfunctional at baseline, and support the idea that interictal spikes disrupt cognitive processes related to the underlying tissue.
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Affiliation(s)
- Hoameng Ung
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA.,Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA, USA
| | - Christian Cazares
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Ameya Nanivadekar
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - Lohith Kini
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA.,Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA, USA
| | - Joost Wagenaar
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA, USA.,Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
| | - Danielle Becker
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
| | - Abba Krieger
- Department of Statistics, University of Pennsylvania, Philadelphia, PA, USA
| | - Timothy Lucas
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA, USA.,Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Brian Litt
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA.,Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA, USA.,Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
| | - Kathryn A Davis
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA, USA.,Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA
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Bromley RL, Leeman BA, Baker GA, Meador KJ. Cognitive and neurodevelopmental effects of antiepileptic drugs. Epilepsy Behav 2011; 22:9-16. [PMID: 21684214 PMCID: PMC6320692 DOI: 10.1016/j.yebeh.2011.04.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Accepted: 04/05/2011] [Indexed: 11/17/2022]
Abstract
This article primarily represents the contributions of two young investigators to the understanding of the neuropsychological consequences of epilepsy and its treatment. The authors have reviewed two key areas of importance: the complex relationship between cognitive dysfunction and epilepsy and the risks of cognitive dysfunction in children as a consequence of in utero exposure to antiepileptic drug treatment. The work of two young investigators is presented and future research needs are outlined.
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Affiliation(s)
- Rebecca L. Bromley
- Division of Clinical Psychology, School of Psychological Sciences, University of Manchester, Manchester, UK
| | - Beth A. Leeman
- Department of Neurology Emory University, Atlanta, GA, USA
| | - Gus A. Baker
- Department of Molecular and Clinical Pharmacology. University of Liverpool, Liverpool, UK,Corresponding author at: Department of Molecular and Clinical Pharmacology, Clinical Sciences Centre for Research and Education, Lower Lane, Liverpool L97LJ, UK. Fax: + 44 151 529 5468. (G.A. Baker)
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Fisher RS, Engel JJ. Definition of the postictal state: when does it start and end? Epilepsy Behav 2010; 19:100-4. [PMID: 20692877 DOI: 10.1016/j.yebeh.2010.06.038] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Accepted: 06/17/2010] [Indexed: 11/19/2022]
Abstract
The postictal state is the abnormal condition occurring between the end of an epileptic seizure and return to baseline condition. Applying this definition operationally can be difficult, especially for complex partial seizures, where cognitive and sensorimotor impairments merge imperceptibly into the postictal state. Many patients are unaware of even having had a seizure. Electroencephalography sometimes helps to distinguish ictal from postictal periods, but may demonstrate focal slowing both during and after a seizure. Epileptiform electroencephalographic changes do not always correspond precisely to behavioral changes, especially with scalp recordings. The postictal state ends at the interictal state, but this too can be ambiguous. Interictal spikes and spike-waves can be associated with cognitive and behavioral impairments, suggesting that they may represent fragments of ictal episodes. Except where boundaries are clear, it is better to describe a sequence of behaviors and electroencephalographic changes, without labeling arbitrary stages as being ictal or postictal.
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Affiliation(s)
- Robert S Fisher
- Department of Neurology and Neurological Science, Stanford University School of Medicine, Stanford, CA 94305-5235, USA.
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Trimble MR, Thompson PJ. Memory, anticonvulsant drugs and seizures. ACTA NEUROLOGICA SCANDINAVICA. SUPPLEMENTUM 2009; 89:31-41. [PMID: 6800211 DOI: 10.1111/j.1600-0404.1981.tb02360.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Sunmonu TA, Komolafe MA, Ogunrin AO, Oladimeji BY, Ogunniyi A. Intellectual impairment in patients with epilepsy in Ile-Ife, Nigeria. Acta Neurol Scand 2008; 118:395-401. [PMID: 18549417 DOI: 10.1111/j.1600-0404.2008.01054.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Epilepsy is the most common non-infectious neurologic disease in developing countries such as Africa, including Nigeria. This study was designed to assess the intellectual performance of patients with epilepsy (PWE) in Nigeria hoping that the result will serve as the basis for educational, vocational, and social counseling. METHODS Forty-one PWE were studied along with 41 age-, sex- and education-matched healthy controls. A questionnaire was developed and applied to all subjects and history was taken from patients and eyewitness. The intellectual function of each subject was assessed with the aid of Wechsler Adult Intelligence Scale adapted for Nigerians. All patients subsequently had electroencephalography (EEG) performed and the EEG findings were noted. SPSS statistical package was used to analyze the data. RESULT The PWE performed poorly on the verbal IQ, performance IQ, and full scale IQ scores when compared with controls (P < 0.05) and 20% of PWE had mental retardation. Long duration of epilepsy, long duration of antiepileptic drug therapy, younger age at onset of epilepsy, increased frequency of seizures, and low educational status were found to have negative impacts on intellectual performance in PWE (P < 0.05) while seizure types and type of antiepileptic drugs (carbamazepine or phenytoin) did not influence intellectual performance. CONCLUSION This study shows that PWE had significant intellectual impairment when compared with controls. In addition, long duration of epilepsy, long duration of AED therapy, earlier age of onset, increased seizure frequency, and low educational status had a negative impact on intellectual functioning in PWE.
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Affiliation(s)
- T A Sunmonu
- Neurology Unit, Department of Medicine, Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife, Osun State, Nigeria.
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Tassinari CA, Rubboli G. Cognition and Paroxysmal EEG Activities: From a Single Spike to Electrical Status Epilepticus during Sleep. Epilepsia 2006; 47 Suppl 2:40-3. [PMID: 17105458 DOI: 10.1111/j.1528-1167.2006.00686.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Epileptic EEG paroxysms can interfere with cognitive processes producing transitory effects, such as those related to a single spike, as well as long-lasting effects, such as in electrical status epilepticus during slow-wave sleep (ESES). Focal spike-related disruption of cortical functions can produce transitory cognitive impairment, with neuroanatomical specificity between the site of the epileptic focus and the impaired cognitive tasks. ESES represents a model of the long-lasting effects of continuous spike-wave activity on higher cortical functions. The duration of ESES and the localization of interictal foci seem to play a major role in influencing the degree and type of cognitive dysfunction, suggesting that the ESES clinical picture results from a localized disruption of EEG activity caused by focal epileptic activity during sleep. Recently, Giulio Tononi's group reported that a local increase of slow-wave activity (SWA) during sleep after learning is associated with improved performance of the learned task after sleep (Huber et al., Nature 2004;430:78-81). On the basis of these findings, we can speculate that prolonged focal epileptic activity during sleep (as occurring in ESES) interferes with local SWA at the site of the epileptic focus, impairing the neural processes and, possibly, the local plastic changes associated with learning and other cognitive functions.
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Abstract
Seizures are not the only obstacles that individuals with epilepsy must overcome. Treatment of epilepsy must take into consideration that patients with epilepsy often face some form of depression, such as peri-ictal depression, ictal depression, interictal depression, or postictal depression, as well as an elevated risk of suicide. Elderly patients, in particular, require special consideration, since aging affects pharmacokinetics and pharmacodynamics; women of childbearing age also require additional counseling. Treatment strategies that focus only on seizure reduction are inadequate and unsuccessful in up to one half of all patients with epilepsy. Epilepsy requires broad treatment strategies that address the needs of the whole patient. Age, genetic factors, gender, diet, use of alcohol and nicotine, comorbidities, and polypharmacy all are important factors to consider in determining a successful epilepsy treatment strategy. Epilepsy affects many aspects of psychosocial function, and optimal outcomes require that the needs of the whole patient be adequately addressed.
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Affiliation(s)
- Günter Krämer
- Swiss Epilepsy Centre, Bleulerstrasse 60, CH-8008 Zurich, Switzerland.
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15
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Hermann B, Seidenberg M. Executive system dysfunction in temporal lobe epilepsy: effects of nociferous cortex versus hippocampal pathology. J Clin Exp Neuropsychol 1995; 17:809-19. [PMID: 8847387 DOI: 10.1080/01688639508402430] [Citation(s) in RCA: 110] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This investigation contrasted two hypotheses regarding executive system dysfunction in temporal lobe epilepsy. The nociferous cortex hypothesis posits that epileptogenic cortex adversely affects the extratemporal regions that mediate executive system abilities, thereby resulting in performance deficits. The hippocampal hypothesis suggests that such impairments are due to the fact that the human hippocampi are directly involved in the mediation of some executive system functions and performance deficits are therefore directly attributable to hippocampal pathology. Seventy-four patients who underwent anterior temporal lobectomy were administered the Wisconsin Card Sorting Test preoperatively and approximately 6 months postoperatively. Presence or absence of hippocampal sclerosis was determined by histopathological analysis. Three specific and contrasting predictions were tested and in each instance the findings supported the nociferous cortex hypothesis.
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Affiliation(s)
- B Hermann
- Epi-Care Center, Baptist Memorial Hospital, University of Tennessee, Memphis, USA
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Durwen HF, Elger CE. Verbal learning differences in epileptic patients with left and right temporal lobe foci--a pharmacologically induced phenomenon? Acta Neurol Scand 1993; 87:1-8. [PMID: 8424306 DOI: 10.1111/j.1600-0404.1993.tb04066.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A total of 27 patients with medically intractable complex partial seizures has been investigated for effects of anticonvulsant drugs on mental abilities, particularly on verbal memory performance. Fourteen patients with right (RTLE) and 13 with left (LTLE) temporal lobe epilepsy have been tested with a word list learning paradigm under the conditions of full and reduced anticonvulsant medication. Memory performance has significantly improved with drug reduction, however only for the LTLE group. In addition, significant group differences for verbal memory between LTLE and RTLE subjects under full medication have completely disappeared with drug reduction. Finally this investigation demonstrates, that very specific and circumscribed steps of verbal memory processing, particularly retrieval abilities after interference, are affected by anticonvulsants. These findings underline the importance of pharmacological effects on cognition and suggest to reevaluate their relevance compared to other contributing factors.
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Affiliation(s)
- H F Durwen
- Department of Neurology, Ruhr-University, Knappschaftskrankenhaus, Bochum, Germany
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Peele DB, Gilbert ME. Functional dissociation of acute and persistent cognitive deficits accompanying amygdala-kindled seizures. Behav Brain Res 1992; 48:65-76. [PMID: 1622555 DOI: 10.1016/s0166-4328(05)80140-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The effects of amygdala-kindled seizures on cognitive function were examined using long-delay flavor-aversion and passive-avoidance conditioning paradigms in rats. Experiments were conducted to compare the functional consequences of unilateral and bilateral kindled seizures (transient deficits) with those due to a kindling history only (persistent deficits). Animals with a history of unilateral or bilateral kindling demonstrated flavor-aversion conditioning that varied inversely with the delay separating saccharin (CS) and lithium (US). Unilateral stimulation during the CS-US interval produced an attenuation of flavor-aversion conditioning that was independent of delay value; bilateral stimulation eliminated conditioning all together. The effects of kindling and kindled seizures on passive-avoidance conditioning were functionally identical. Animals with a history of unilateral kindling demonstrated strong evidence of conditioning with no effect of posttraining seizures. In contrast, animals with a history of bilateral kindling were impaired in a passive-avoidance task. The impairment was evident in the presence or absence of seizure induction during training. Electrographic and behavioral indices of epileptiform activity produced by unilateral and bilateral stimulation failed to reveal any differences in seizure duration or severity. The results support the conclusion that cognitive disruption by amygdala-kindled seizures is task-dependent, does not show a temporal dependence, and cannot be explained on the basis of electrographic or behavioral measures of seizure severity alone.
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Affiliation(s)
- D B Peele
- Mantech Environmental Technology Incorporated, Research Triangle Park, NC 27709
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Abstract
Subclinical generalized spike-wave discharges are often accompanied by transitory cognitive impairment, demonstrable by psychological testing during EEG recording. Transitory cognitive impairment is demonstrated most readily by difficult tasks and during generalized regular spike-wave bursts lasting for more than 3 s, but can also be found during briefer and even focal discharges. That this is not simply a consequence of global inattention is shown by the fact that focal discharges exhibit some specificity: left-sided focal spiking is more likely to produce errors on verbal tasks, for instance, whereas right-sided discharges are more often accompanied by impairment in handling nonverbal material. Both learning difficulties in general and specific abnormal patterns of cognitive functioning are well documented in children with epilepsy and are most pronounced in those with frequent interictal discharges. However, there is now evidence that intermittent cognitive impairment due to the discharges themselves contributes significantly to such neurophysiological abnormalities. The significance of transitory cognitive impairment accompanying subclinical EEG discharges for everyday functioning is uncertain, but there is experimental evidence that subclinical discharges may be accompanied by disruption of educational skills in children or by impairment of driving performance in motorists. In some individuals, suppression of discharges by antiepileptic drugs has demonstrably improved psychological function, but further work is required to determine the indications for such treatment.
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Affiliation(s)
- C D Binnie
- Department of Clinical Neurophysiology, Maudsley Hospital, London, England
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Bornstein R, Pakalnis A, Drake M. Verbal and nonverbal memory and learning in patients with complex partial seizures of temporal lobe origin. ACTA ACUST UNITED AC 1988. [DOI: 10.1016/s0896-6974(88)80015-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Collins RC. Epilepsy: Insights into Higher Brain Functions in Humans. Compr Physiol 1987. [DOI: 10.1002/cphy.cp010520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Lieb JP, Rausch R, Engel J, Brown WJ, Crandall PH. Changes in intelligence following temporal lobectomy: relationship to EEG activity, seizure relief, and pathology. Epilepsia 1982; 23:1-13. [PMID: 7056247 DOI: 10.1111/j.1528-1157.1982.tb05046.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Pre- and posttemporal lobectomy measures of intelligence and memory in 36 patients with medically refractory complex partial seizures were compared with (1) various aspects of presurgical ictal and interictal EEG activity derived from surface and deep electrodes, (2) postlobectomy seizure relief, and (3) pathological findings in the resected lobe. With respect to interictal EEG data, bilaterally synchronous surface spikes (accompanied or unaccompanied by simultaneous deep spikes) and sharp waves were significantly correlated with lower prelobectomy intelligence scores and a drop in these scores following lobectomy. With respect to ictal EEG data, bilaterally synchronous and multifocal onsets were significantly correlated with a postlobectomy drop in intelligence scores. Patients with poor postlobectomy seizure relief tended to have lower presurgical intelligence scores and a drop in intelligence scores following lobectomy. The patients most likely to show a postlobectomy drop in intelligence were those demonstrating some combination of poor seizure relief, an absence of pathology in the resected specimen, or EEG signs indicative of poor seizure relief. Postlobectomy changes in intellectual status are therefore not necessarily exclusively attributable to the amount of postlobectomy seizure relief experienced by these patients, but might be due to a combination of factors.
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