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Lidzba K, Afridi Z, Romano F, Wingeier K, Bigi S, Studer M. Impaired episodic verbal memory recall after 1 week and elevated forgetting in children after mild traumatic brain injury - results from a short-term longitudinal study. Front Psychol 2024; 15:1359566. [PMID: 38887630 PMCID: PMC11182044 DOI: 10.3389/fpsyg.2024.1359566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 05/10/2024] [Indexed: 06/20/2024] Open
Abstract
Objective There is preliminary evidence that children after traumatic brain injury (TBI) have accelerated long-term forgetting (ALF), i.e., an adequate learning and memory performance in standardized memory tests, but an excessive rate of forgetting over delays of days or weeks. The main aim of this study was to investigate episodic memory performance, including delayed retrieval 1 week after learning, in children after mild TBI (mTBI). Methods This prospective study with two time-points (T1: 1 week after injury and T2: 3-6 months after injury), included data of 64 children after mTBI and 57 healthy control children aged between 8 and 16 years. We assessed episodic learning and memory using an auditory word learning test and compared executive functions (interference control, working memory, semantic fluency and flexibility) and divided attention between groups. We explored correlations between memory performance and executive functions. Furthermore, we examined predictive factors for delayed memory retrieval 1 week after learning as well as for forgetting over time. Results Compared to healthy controls, patients showed an impaired delayed recall and recognition performance 3-6 months after injury. Executive functions, but not divided attention, were reduced in children after mTBI. Furthermore, parents rated episodic memory as impaired 3-6 months after injury. Additionally, verbal learning and group, but not executive functions, were predictive for delayed recall performance at both time-points, whereas forgetting was predicted by group. Discussion Delayed recall and forgetting over time were significantly different between groups, both post-acutely and in the chronic phase after pediatric mTBI, even in a very mildly injured patient sample. Delayed memory performance should be included in clinical evaluations of episodic memory and further research is needed to understand the mechanisms of ALF.
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Affiliation(s)
- Karen Lidzba
- Division of Neuropediatrics, Development and Rehabilitation, Department of Paediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Zainab Afridi
- Division of Neuropediatrics, Development and Rehabilitation, Department of Paediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Fabrizio Romano
- Division of Paediatric Emergency Medicine, Department of Paediatrics, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Kevin Wingeier
- Department of Psychosomatics and Psychiatry, University Children’s Hospital Zurich, Zürich, Switzerland
| | - Sandra Bigi
- Institute for Social and Preventive Medicine, University of Bern, Bern, Switzerland
- Division of Pediatric Neurology, Department of Pediatrics, Children’s Hospital of Central Switzerland, Lucerne, Switzerland
| | - Martina Studer
- Department of Pediatric Neurology and Developmental Medicine, University Children’s Hospital Basel (UKBB), Basel, Switzerland
- Department of Clinical Research, University of Basel, Basel, Switzerland
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Department of Psychology, University of Basel, Basel, Switzerland
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Höller Y, Eyjólfsdóttir SG, Rusiňák M, Guðmundsson LS, Trinka E. Movement Termination of Slow-Wave Sleep-A Potential Biomarker? Brain Sci 2024; 14:493. [PMID: 38790471 PMCID: PMC11120257 DOI: 10.3390/brainsci14050493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 05/06/2024] [Accepted: 05/11/2024] [Indexed: 05/26/2024] Open
Abstract
The duration of slow-wave sleep (SWS) is related to the reported sleep quality and to the important variables of mental and physical health. The internal cues to end an episode of SWS are poorly understood. One such internal cue is the initiation of a body movement, which is detectable as electromyographic (EMG) activity in sleep-electroencephalography (EEG). In the present study, we characterized the termination of SWS episodes by movement to explore its potential as a biomarker. To this end, we characterized the relation between the occurrence of SWS termination by movement and individual characteristics (age, sex), SWS duration and spectral content, chronotype, depression, medication, overnight memory performance, and, as a potential neurological application, epilepsy. We analyzed 94 full-night EEG-EMG recordings (75/94 had confirmed epilepsy) in the video-EEG monitoring unit of the EpiCARE Centre Salzburg, Austria. Segments of SWS were counted and rated for their termination by movement or not through the visual inspection of continuous EEG and EMG recordings. Multiple linear regression was used to predict the number of SWS episodes that ended with movement by depression, chronotype, type of epilepsy (focal, generalized, no epilepsy, unclear), medication, gender, total duration of SWS, occurrence of seizures during the night, occurrence of tonic-clonic seizures during the night, and SWS frequency spectra. Furthermore, we assessed whether SWS movement termination was related to overnight memory retention. According to multiple linear regression, patients with overall longer SWS experienced more SWS episodes that ended with movement (t = 5.64; p = 0.001). No other variable was related to the proportion of SWS that ended with movement, including no epilepsy-related variable. A small sample (n = 4) of patients taking Sertraline experienced no SWS that ended with movement, which was significant compared to all other patients (t = 8.00; p < 0.001) and to n = 35 patients who did not take any medication (t = 4.22; p < 0.001). While this result was based on a small subsample and must be interpreted with caution, it warrants replication in a larger sample with and without seizures to further elucidate the role of the movement termination of SWS and its potential to serve as a biomarker for sleep continuity and for medication effects on sleep.
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Affiliation(s)
- Yvonne Höller
- Faculty of Psychology, University of Akureyri, 600 Akureyri, Iceland; (S.G.E.); (M.R.)
| | | | - Matej Rusiňák
- Faculty of Psychology, University of Akureyri, 600 Akureyri, Iceland; (S.G.E.); (M.R.)
- Faculty of Social Studies, Masaryk University, 601 77 Brno, Czech Republic
| | | | - Eugen Trinka
- Department of Neurology, Neurointensive Care and Neurorehabilitation, Christian-Doppler University Hospital, Paracelsus Medical University, Centre for Neuroscience Salzburg, Member of the European Reference Network, EpiCARE, 5020 Salzburg, Austria
- Neuroscience Institute, Christian-Doppler University Hospital, Centre for Cognitive Neuroscience, 5020 Salzburg, Austria
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Höller Y, Eyjólfsdóttir S, Van Schalkwijk FJ, Trinka E. The effects of slow wave sleep characteristics on semantic, episodic, and procedural memory in people with epilepsy. Front Pharmacol 2024; 15:1374760. [PMID: 38725659 PMCID: PMC11079234 DOI: 10.3389/fphar.2024.1374760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 04/04/2024] [Indexed: 05/12/2024] Open
Abstract
Slow wave sleep (SWS) is highly relevant for verbal and non-verbal/spatial memory in healthy individuals, but also in people with epilepsy. However, contradictory findings exist regarding the effect of seizures on overnight memory retention, particularly relating to procedural and non-verbal memory, and thorough examination of episodic memory retention with ecologically valid tests is missing. This research explores the interaction of SWS duration with epilepsy-relevant factors, as well as the relation of spectral characteristics of SWS on overnight retention of procedural, verbal, and episodic memory. In an epilepsy monitoring unit, epilepsy patients (N = 40) underwent learning, immediate and 12 h delayed testing of memory retention for a fingertapping task (procedural memory), a word-pair task (verbal memory), and an innovative virtual reality task (episodic memory). We used multiple linear regression to examine the impact of SWS duration, spectral characteristics of SWS, seizure occurrence, medication, depression, seizure type, gender, and epilepsy duration on overnight memory retention. Results indicated that none of the candidate variables significantly predicted overnight changes for procedural memory performance. For verbal memory, the occurrence of tonic-clonic seizures negatively impacted memory retention and higher psychoactive medication load showed a tendency for lower verbal memory retention. Episodic memory was significantly impacted by epilepsy duration, displaying a potential nonlinear impact with a longer duration than 10 years negatively affecting memory performance. Higher drug load of anti-seizure medication was by tendency related to better overnight retention of episodic memory. Contrary to expectations longer SWS duration showed a trend towards decreased episodic memory performance. Analyses on associations between memory types and EEG band power during SWS revealed lower alpha-band power in the frontal right region as significant predictor for better episodic memory retention. In conclusion, this research reveals that memory modalities are not equally affected by important epilepsy factors such as duration of epilepsy and medication, as well as SWS spectral characteristics.
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Affiliation(s)
- Yvonne Höller
- Faculty of Psychology, University of Akureyri, Akureyri, Iceland
| | | | - Frank Jasper Van Schalkwijk
- Hertie-Institute for Clinical Brain Research, Center for Neurology, University Medical Center Tübingen, Tübingen, Germany
| | - Eugen Trinka
- Department of Neurology, Christian Doppler University Hospital, Member of the European Reference Network EpiCARE, Neuroscience Institute, Paracelsus Medical University and Centre for Cognitive Neuroscience Salzburg, Salzburg, Austria
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Mayor C, Moser C, Korff C. Long-term memory consolidation of new words in children with self-limited epilepsy with centro-temporal spikes. Epilepsy Behav 2024; 153:109720. [PMID: 38428174 DOI: 10.1016/j.yebeh.2024.109720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 02/21/2024] [Accepted: 02/22/2024] [Indexed: 03/03/2024]
Abstract
Accelerated long-term forgetting has been studied and demonstrated in adults with epilepsy. In contrast, the question of long-term consolidation (delays > 1 day) in children with epilepsy shows conflicting results. However, childhood is a period of life in which the encoding and long-term storage of new words is essential for the development of knowledge and learning. The aim of this study was therefore to investigate long-term memory consolidation skills in children with self-limited epilepsy with centro-temporal spikes (SeLECTS), using a paradigm exploring new words encoding skills and their long-term consolidation over one-week delay. As lexical knowledge, working memory skills and executive/attentional skills has been shown to contribute to long-term memory/new word learning, we added standardized measures of oral language and executive/attentional functions to explore the involvement of these cognitive skills in new word encoding and consolidation. The results showed that children with SeLECTS needed more repetitions to encode new words, struggled to encode the phonological forms of words, and when they finally reached the level of the typically developing children, they retained what they had learned, but didn't show improved recall skills after a one-week delay, unlike the control participants. Lexical knowledge, verbal working memory skills and phonological skills contributed to encoding and/or recall abilities, and interference sensitivity appeared to be associated with the number of phonological errors during the pseudoword encoding phase. These results are consistent with the functional model linking working memory, phonology and vocabulary in a fronto-temporo-parietal network. As SeLECTS involves perisylvian dysfunction, the associations between impaired sequence storage (phonological working memory), phonological representation storage and new word learning are not surprising. This dual impairment in both encoding and long-term consolidation may result in large learning gap between children with and without epilepsy. Whether these results indicate differences in the sleep-induced benefits required for long-term consolidation or differences in the benefits of retrieval practice between the epilepsy group and healthy children remains open. As lexical development is associated with academic achievement and comprehension, the impact of such deficits in learning new words is certainly detrimental.
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Affiliation(s)
- C Mayor
- Child Neuropsychology Unit, Faculty of Psychology and Educational Sciences, University of Geneva, Switzerland.
| | - C Moser
- Child Neuropsychology Unit, Faculty of Psychology and Educational Sciences, University of Geneva, Switzerland
| | - C Korff
- Pediatric Neurology Unit, University Hospitals of Geneva, Geneva, Switzerland
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Dontaine P, Rouge C, Urbain C, Galer S, Raffoul R, Nonclercq A, Van Dyck D, Baijot S, Aeby A. How the Spreading and Intensity of Interictal Epileptic Activity Are Associated with Visuo-Spatial Skills in Children with Self-Limited Focal Epilepsy with Centro-Temporal Spikes. Brain Sci 2023; 13:1566. [PMID: 38002525 PMCID: PMC10669985 DOI: 10.3390/brainsci13111566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 10/20/2023] [Accepted: 11/03/2023] [Indexed: 11/26/2023] Open
Abstract
This paper investigates brain-behaviour associations between interictal epileptic discharges and cognitive performance in a population of children with self-limited focal epilepsy with centro-temporal spikes (SeLECTS). Sixteen patients with SeLECTS underwent an extensive neuropsychological assessment, including verbal short-term and episodic memory, non-verbal short-term memory, attentional abilities and executive function. Two quantitative EEG indices were analysed, i.e., the Spike Wave Index (SWI) and the Spike Wave Frequency (SWF), and one qualitative EEG index, i.e., the EEG score, was used to evaluate the spreading of focal SW to other parts of the brain. We investigated associations between EEG indices and neuropsychological performance with non-parametric Spearman correlation analyses, including correction for multiple comparisons. The results showed a significant negative correlation between (i) the awake EEG score and the Block Tapping Test, a visuo-spatial short-term memory task, and (ii) the sleep SWI and the Tower of London, a visuo-spatial planning task (pcorr < 0.05). These findings suggest that, in addition to the usual quantitative EEG indices, the EEG analysis should include the qualitative EEG score evaluating the spreading of focal SW to other parts of the brain and that neuropsychological assessment should include visuo-spatial skills.
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Affiliation(s)
- Pauline Dontaine
- Department of Pediatric Neurology, Hopital Universitaire de Bruxelles (H.U.B.), Queen Fabiola Children’s University Hospital (HUDERF), Université Libre de Bruxelles (ULB), 1020 Brussels, Belgium
| | - Coralie Rouge
- Department of Pediatric Neurology, Hopital Universitaire de Bruxelles (H.U.B.), Queen Fabiola Children’s University Hospital (HUDERF), Université Libre de Bruxelles (ULB), 1020 Brussels, Belgium
- Neuropsychology and Functional Neuroimaging Research Group (UR2NF), Center for Research in Cognition & Neurosciences (CRCN), ULB Neurosciences Institute, Université Libre de Bruxelles (ULB), 1050 Brussels, Belgium
- Laboratoire de Neuroanatomie et Neuroimagerie Translationnelles (LN2T), UNI-ULB Neurosciences Institute, Hôpital Erasme, Université Libre de Bruxelles (ULB), 1050 Brussels, Belgium
| | - Charline Urbain
- Neuropsychology and Functional Neuroimaging Research Group (UR2NF), Center for Research in Cognition & Neurosciences (CRCN), ULB Neurosciences Institute, Université Libre de Bruxelles (ULB), 1050 Brussels, Belgium
- Laboratoire de Neuroanatomie et Neuroimagerie Translationnelles (LN2T), UNI-ULB Neurosciences Institute, Hôpital Erasme, Université Libre de Bruxelles (ULB), 1050 Brussels, Belgium
| | - Sophie Galer
- Department of Pediatric Neurology, Hopital Universitaire de Bruxelles (H.U.B.), Queen Fabiola Children’s University Hospital (HUDERF), Université Libre de Bruxelles (ULB), 1020 Brussels, Belgium
- Neuropsychology and Functional Neuroimaging Research Group (UR2NF), Center for Research in Cognition & Neurosciences (CRCN), ULB Neurosciences Institute, Université Libre de Bruxelles (ULB), 1050 Brussels, Belgium
- Department of Neuropsychology and Speech Therapy, Queen Fabiola Children’s University Hospital (HUDERF)-Hôpital Universitaire de Bruxelles (H.U.B), Université libre de Bruxelles (ULB), 1020 Brussels, Belgium
| | - Romain Raffoul
- BEAMS (Bio-, Electro- And Mechanical Systems), Université Libre de Bruxelles (ULB), 1050 Brussels, Belgium
| | - Antoine Nonclercq
- BEAMS (Bio-, Electro- And Mechanical Systems), Université Libre de Bruxelles (ULB), 1050 Brussels, Belgium
| | - Dorine Van Dyck
- Department of Pediatric Neurology, Hopital Universitaire de Bruxelles (H.U.B.), Queen Fabiola Children’s University Hospital (HUDERF), Université Libre de Bruxelles (ULB), 1020 Brussels, Belgium
- Department of Neuropsychology and Speech Therapy, Queen Fabiola Children’s University Hospital (HUDERF)-Hôpital Universitaire de Bruxelles (H.U.B), Université libre de Bruxelles (ULB), 1020 Brussels, Belgium
| | - Simon Baijot
- Department of Pediatric Neurology, Hopital Universitaire de Bruxelles (H.U.B.), Queen Fabiola Children’s University Hospital (HUDERF), Université Libre de Bruxelles (ULB), 1020 Brussels, Belgium
- Neuropsychology and Functional Neuroimaging Research Group (UR2NF), Center for Research in Cognition & Neurosciences (CRCN), ULB Neurosciences Institute, Université Libre de Bruxelles (ULB), 1050 Brussels, Belgium
- Department of Neuropsychology and Speech Therapy, Queen Fabiola Children’s University Hospital (HUDERF)-Hôpital Universitaire de Bruxelles (H.U.B), Université libre de Bruxelles (ULB), 1020 Brussels, Belgium
| | - Alec Aeby
- Department of Pediatric Neurology, Hopital Universitaire de Bruxelles (H.U.B.), Queen Fabiola Children’s University Hospital (HUDERF), Université Libre de Bruxelles (ULB), 1020 Brussels, Belgium
- Neuropsychology and Functional Neuroimaging Research Group (UR2NF), Center for Research in Cognition & Neurosciences (CRCN), ULB Neurosciences Institute, Université Libre de Bruxelles (ULB), 1050 Brussels, Belgium
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Skorucak J, Bölsterli BK, Storz S, Leach S, Schmitt B, Ramantani G, Huber R. Automated analysis of a large-scale paediatric dataset illustrates the interdependent relationship between epilepsy and sleep. Sci Rep 2023; 13:12882. [PMID: 37553387 PMCID: PMC10409812 DOI: 10.1038/s41598-023-39984-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 08/03/2023] [Indexed: 08/10/2023] Open
Abstract
Slow waves are an electrophysiological characteristic of non-rapid eye movement sleep and a marker of the restorative function of sleep. In certain pathological conditions, such as different types of epilepsy, slow-wave sleep is affected by epileptiform discharges forming so-called "spike-waves". Previous evidence shows that the overnight change in slope of slow waves during sleep is impaired under these conditions. However, these past studies were performed in a small number of patients, considering only short segments of the recording night. Here, we screened a clinical data set of 39'179 pediatric EEG recordings acquired in the past 25 years (1994-2019) at the University Children's Hospital Zurich and identified 413 recordings of interest. We applied an automated approach based on machine learning to investigate the relationship between sleep and epileptic spikes in this large-scale data set. Our findings show that the overnight change in the slope of slow waves was correlated with the spike-wave index, indicating that the impairment of the net reduction in synaptic strength during sleep is spike dependent.
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Affiliation(s)
- Jelena Skorucak
- Child Development Center, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
- Children's Research Center, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Bigna K Bölsterli
- Children's Research Center, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
- Department of Pediatric Neurology, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
- Department of Pediatric Neurology, Children's Hospital of Eastern Switzerland, St. Gallen, Switzerland
| | - Sarah Storz
- Child Development Center, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
- Children's Research Center, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
- Department of Pediatric Neurology, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Sven Leach
- Child Development Center, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
- Children's Research Center, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Bernhard Schmitt
- Children's Research Center, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
- Department of Pediatric Neurology, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Georgia Ramantani
- Children's Research Center, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
- Department of Pediatric Neurology, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Reto Huber
- Child Development Center, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland.
- Children's Research Center, University Children's Hospital Zurich, University of Zurich, Zurich, Switzerland.
- Department of Child and Adolescent Psychiatry and Psychotherapy, Psychiatric Hospital, University of Zurich, Zurich, Switzerland.
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Moysés-Oliveira M, Paschalidis M, Souza-Cunha LA, Esteves-Guerreiro PA, Adami LNG, Kloster AK, Mosini AC, Moreira GA, Doria S, Tempaku PF, Pires GN, Andersen ML, Tufik S. Genetic basis of sleep phenotypes and rare neurodevelopmental syndromes reveal shared molecular pathways. J Neurosci Res 2023; 101:1058-1067. [PMID: 36791049 DOI: 10.1002/jnr.25180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/13/2023] [Accepted: 01/31/2023] [Indexed: 02/16/2023]
Abstract
Sleep-related phenotypes have been frequently reported in early on-set epileptic encephalopathies and in developmental delay syndromes, in particular in syndromes related to autism spectrum disorder. Yet the convergent pathogenetic mechanisms between these comorbidities are largely unknown. We first performed a gene enrichment study that identified shared risk genes among rare epileptic encephalopathies/neurodevelopmental disorders, rare developmental delay genetic syndromes and sleep disturbances. We then determined cellular and molecular pathways enriched among genes shared between sleep phenotypes and those two early onset mental illnesses, aiming to identify genetic disparities and commonalities among these phenotypic groups. The sleep gene set was observed as significantly overlapped with the two gene lists associated to rare genetic syndromes (i.e., epileptic encephalopathies/neurodevelopmental disorders and developmental delay gene sets), suggesting shared genetic contribution. Similarities across significantly enriched pathways between the two intersect lists comprehended mostly synapse-related pathways, such as retrograde endocannabinoid signaling, serotonergic, and GABAergic synapse. Network analysis indicates epileptic encephalopathies/neurodevelopmental disorders versus sleep-specific clusters and developmental delay versus sleep-specific clusters related to synaptic and transcriptional regulation, respectively. Longstanding functional patterns previously described in epileptic encephalopathies and neurodevelopmental disorders genetic architecture were recaptured after dissecting the overlap between the genes associated to those developmental phenotypes and sleep disturbances, suggesting that during neurodevelopment different molecular and functional mechanisms are related to alterations on circadian rhythm. The overlapping gene set and biological pathways highlighted by this study may serve as a primer for new functional investigations of shared molecular mechanisms between sleep disturbances and rare developmental syndromes.
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Affiliation(s)
| | | | | | | | | | | | | | - Gustavo A Moreira
- Sleep Institute, São Paulo, Brazil.,Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, Brazil.,Departamento de Pediatria, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Sandra Doria
- Sleep Institute, São Paulo, Brazil.,Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Priscila F Tempaku
- Sleep Institute, São Paulo, Brazil.,Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Gabriel N Pires
- Sleep Institute, São Paulo, Brazil.,Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Monica L Andersen
- Sleep Institute, São Paulo, Brazil.,Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Sergio Tufik
- Sleep Institute, São Paulo, Brazil.,Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, Brazil
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Schiller K, von Ellenrieder N, Avigdor T, El Kosseifi C, Abdallah C, Minato E, Gotman J, Frauscher B. Focal epilepsy impacts rapid eye movement sleep microstructure. Sleep 2023; 46:zsac250. [PMID: 36242588 PMCID: PMC9905780 DOI: 10.1093/sleep/zsac250] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/16/2022] [Indexed: 12/12/2022] Open
Abstract
STUDY OBJECTIVES Whereas there is plenty of evidence on the influence of epileptic activity on non-rapid eye movement (NREM) sleep macro- and micro-structure, data on the impact of epilepsy on rapid eye movement (REM) sleep remains sparse. Using high-density electroencephalography (HD-EEG), we assessed global and focal disturbances of sawtooth waves (STW) as cortically generated sleep oscillations of REM sleep in patients with focal epilepsy. METHODS Twenty-two patients with drug-resistant focal epilepsy (13 females; mean age, 32.6 ± 10.7 years; 12 temporal lobe epilepsy) and 12 healthy controls (3 females; 24.0 ± 3.2 years) underwent combined overnight HD-EEG and polysomnography. STW rate, duration, frequency, power, spatial extent, IED rates and sleep homeostatic properties were analyzed. RESULTS STW rate and duration were reduced in patients with focal epilepsy compared to healthy controls (rate: 0.64/min ± 0.46 vs. 1.12/min ± 0.41, p = .005, d = -0.98; duration: 3.60 s ± 0.76 vs. 4.57 ± 1.00, p = .003, d = -1.01). Not surprisingly given the fronto-central maximum of STW, the reductions were driven by extratemporal lobe epilepsy patients (rate: 0.45/min ± 0.31 vs. 1.12/min ± 0.41, p = .0004, d = -1.35; duration: 3.49 s ± 0.92 vs. 4.57 ± 1.00, p = .017, d = -0.99) and were more pronounced in the first vs. the last sleep cycle (rate first cycle patients vs. controls: 0.60/min ± 0.49 vs. 1.10/min ± 0.55, p = .016, d = -0.90, rate last cycle patients vs. controls: 0.67/min ± 0.51 vs. 0.99/min ± 0.49, p = .11, d = -0.62; duration first cycle patients vs. controls: 3.60s ± 0.76 vs. 4.57 ± 1.00, p = .003, d = -1.01, duration last cycle patients vs. controls: 3.66s ± 0.84 vs. 4.51 ± 1.26, p = .039, d = -0.80). There was no regional decrease of STWs in the region with the epileptic focus vs. the contralateral side (all p > .05). CONCLUSION Patients with focal epilepsy and in particular extratemporal lobe epilepsy show a global reduction of STW activity in REM sleep. This may suggest that epilepsy impacts cortically generated sleep oscillations even in REM sleep when epileptic activity is low.
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Affiliation(s)
- Katharina Schiller
- Analytical Neurophysiology Lab, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
- Hospital Group Ostallgaeu-Kaufbeuren, Department of Pediatrics, Kaufbeuren, Germany
- Medical University Innsbruck, Department of Pediatrics, Innsbruck, Austria
| | | | - Tamir Avigdor
- Analytical Neurophysiology Lab, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Charbel El Kosseifi
- Analytical Neurophysiology Lab, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Chifaou Abdallah
- Analytical Neurophysiology Lab, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Erica Minato
- Analytical Neurophysiology Lab, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Jean Gotman
- Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Birgit Frauscher
- Analytical Neurophysiology Lab, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
- Department of Medicine and Center for Neuroscience Studies, Queen’s University; Kingston, Ontario, Canada
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Johnson EC, Atkinson P, Muggeridge A, Chan S, Helen Cross J, Reilly C. Perceived impact of epilepsy on sleep: Views of children with epilepsy, parents and school staff. Epilepsy Behav 2023; 138:109026. [PMID: 36512932 DOI: 10.1016/j.yebeh.2022.109026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 11/16/2022] [Accepted: 11/23/2022] [Indexed: 12/14/2022]
Abstract
OBJECTIVE To gain an understanding of the views of school-aged children with epilepsy, their parents, and school staff regarding the impact of epilepsy on sleep. METHODS As part of the What I Need in School (WINS) study, school-aged children (n = 18) with 'active epilepsy' (taking Anti-Seizure Medications, ASMs, for epilepsy), their parents (n = 68) and school staff (n = 56) were interviewed or completed bespoke questionnaires. Questions focussed on the potential impact of epilepsy on the child's sleep or tiredness in school and the potential impact of sleep/tiredness on learning and behavior. RESULTS Fifty-six percent of children believed that epilepsy affects their sleep while 65% of parents believed that their child had more difficulties with sleep than other children of their age. Seventy-eight percent of parents believed that their child's difficulties were due to epilepsy and 95% believed that their child's difficulties impacted their learning and behavior. Fifty-four percent of school staff believed that the child with epilepsy they supported was more tired/fatigued than their peers, and 86% of school staff believed that the child's increased tiredness affected their learning/behavior. Parents of children with intellectual disabilitiy were significantly more likely to indicate that they felt that their child had more sleep difficulties than other children (p = 0.016). Regarding the impact on their sleep, participating children felt that epilepsy contributed to difficulties in falling and staying asleep and daytime tiredness. Their parents reported a range of potential sleep difficulties and potential impacts on the child's learning and behavior. Parental reported difficulties included daytime tiredness, difficulty falling and staying asleep, and the impact of nocturnal seizures. In terms of impact, parents felt that sleep difficulties impacted negatively cognition and emotional-behavioral functioning. Additionally, parents reported that ASMs and medication for ADHD can contribute to sleep difficulties. School staff felt that many of the children appeared tired/fatigued during the day and this could lead to less engagement with classroom activities, impact attention and processing speed negatively, and contribute to behavioral and emotional difficulties. CONCLUSION The majority of children and parents who responded believed that epilepsy affects the child's sleep. Most parents and school staff also believed that the child's sleep difficulties/excess tiredness were due to the child's epilepsy and that the difficulties significantly impacted the child's learning and behavior. There is a need to better understand the role epilepsy plays in sleep difficulties and associated learning and behavioral impairments. There is also a need to develop interventions to reduce the subsequent impact on child learning and behavior.
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Affiliation(s)
- Emma C Johnson
- Research Department, Young Epilepsy, Lingfield, Surrey RH7 6PW, UK
| | - Patricia Atkinson
- Child Development Centre, Crawley Hospital, West Green Drive, Crawley RH11 7DH, West Sussex, UK
| | - Amy Muggeridge
- Research Department, Young Epilepsy, Lingfield, Surrey RH7 6PW, UK
| | - Samantha Chan
- Great Ormond Street Hospital for Children NHS Trust, Great Ormond Street, London WC1N 3JH, UK; UCL Great Ormond Street Institute of Child Health (ICH), 30 Guilford Street London WC1N 1EH, UK
| | - J Helen Cross
- Research Department, Young Epilepsy, Lingfield, Surrey RH7 6PW, UK; Great Ormond Street Hospital for Children NHS Trust, Great Ormond Street, London WC1N 3JH, UK; UCL Great Ormond Street Institute of Child Health (ICH), 30 Guilford Street London WC1N 1EH, UK
| | - Colin Reilly
- Research Department, Young Epilepsy, Lingfield, Surrey RH7 6PW, UK; UCL Great Ormond Street Institute of Child Health (ICH), 30 Guilford Street London WC1N 1EH, UK.
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10
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Li Y, Chen J, Sun J, Jiang P, Xiang J, Chen Q, Hu Z, Wang X. Changes in functional connectivity in newly diagnosed self-limited epilepsy with centrotemporal spikes and cognitive impairment: An MEG study. Brain Behav 2022; 12:e2830. [PMID: 36408856 PMCID: PMC9759146 DOI: 10.1002/brb3.2830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Revised: 09/23/2022] [Accepted: 11/03/2022] [Indexed: 11/22/2022] Open
Abstract
PURPOSE Our purpose was to explore the relationship between cognitive impairment and neural network changes in patients newly diagnosed with self-limited epilepsy with centrotemporal spikes (SeLECTS). METHODS The Wechsler Intelligence Scale for Children, fourth edition was used to divide all SeLECTS patients into two groups: patients with full-scale intelligence quotient (FSIQ) below 80 that corresponded to cognitive impairment, and patients with FSIQ above 80 that corresponded to a normal cognitive function. The data on the resting state were recorded using magnetoencephalography. The properties of the networks were analyzed using graph theory (GT) analysis. RESULTS The functional connectivity (FC) of the frontal cortex in patients with FSIQ < 80 was reduced in the 12-30 Hz frequency band, and the FC of the posterior cingulate cortex was reduced in the 80-250 and 250-500 Hz frequency bands. The GT analysis showed that patients in the FSIQ < 80 group had higher strength in the 8-12 and 12-30 Hz frequency bands than those in the healthy control and FSIQ > 80 group. However, the path length was reduced in the 80-250 Hz band, and the clustering coefficient was reduced in the 12-30, 80-250, and 250-500 Hz frequency bands. Moreover, the receiver operator characteristic analysis showed that the clustering coefficient in the 12-30 and 80-250 Hz frequency bands, as well as the path length in the 80-250 Hz frequency band possessed a good discriminative ability in distinguishing the FSIQ > 80 group. CONCLUSIONS SeLECTS patients with cognitive impairment in the early stage of the disease developed disordered networks in cognitive-related brain regions. The clustering coefficient in the 12-30 and 80-250 Hz frequency bands as well as the path length in the 80-250 Hz frequency band might be good indicators to distinguish the cognitive impairment of SeLECTS patients at the early stage.
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Affiliation(s)
- Yihan Li
- Department of Neurology, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jinan Chen
- Department of Neurology, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jintao Sun
- Department of Neurology, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Ping Jiang
- Department of Neurology, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jing Xiang
- MEG Center, Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Qiqi Chen
- MEG Center, Nanjing Brain Hospital, Nanjing, Jiangsu, China
| | - Zheng Hu
- Department of Neurology, Nanjing Children's Hospital, Nanjing, Jiangsu, China
| | - Xiaoshan Wang
- Department of Neurology, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
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11
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Okadome T, Yamaguchi T, Mukaino T, Sakata A, Ogata K, Shigeto H, Isobe N, Uehara T. The effect of interictal epileptic discharges and following spindles on motor sequence learning in epilepsy patients. Front Neurol 2022; 13:979333. [PMID: 36438951 PMCID: PMC9686303 DOI: 10.3389/fneur.2022.979333] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 10/25/2022] [Indexed: 09/05/2023] Open
Abstract
PURPOSE Interictal epileptic discharges (IEDs) are known to affect cognitive function in patients with epilepsy, but the mechanism has not been elucidated. Sleep spindles appearing in synchronization with IEDs were recently demonstrated to impair memory consolidation in rat, but this has not been investigated in humans. On the other hand, the increase of sleep spindles at night after learning is positively correlated with amplified learning effects during sleep for motor sequence learning. In this study, we examined the effects of IEDs and IED-coupled spindles on motor sequence learning in patients with epilepsy, and clarified their pathological significance. MATERIALS AND METHODS Patients undergoing long-term video-electroencephalography (LT-VEEG) at our hospital from June 2019 to November 2021 and age-matched healthy subjects were recruited. Motor sequence learning consisting of a finger-tapping task was performed before bedtime and the next morning, and the improvement rate of performance was defined as the sleep-dependent learning effect. We searched for factors associated with the changes in learning effect observed between the periods of when antiseizure medications (ASMs) were withdrawn for LT-VEEG and when they were returned to usual doses after LT-VEEG. RESULTS Excluding six patients who had epileptic seizures at night after learning, nine patients and 11 healthy subjects were included in the study. In the patient group, there was no significant learning effect when ASMs were withdrawn. The changes in learning effect of the patient group during ASM withdrawal were not correlated with changes in sleep duration or IED density; however, they were significantly negatively correlated with changes in IED-coupled spindle density. CONCLUSION We found that the increase of IED-coupled spindles correlated with the decrease of sleep-dependent learning effects of procedural memory. Pathological IED-coupled sleep spindles could hinder memory consolidation, that is dependent on physiological sleep spindles, resulting in cognitive dysfunction in patients with epilepsy.
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Affiliation(s)
- Toshiki Okadome
- Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Takahiro Yamaguchi
- Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Takahiko Mukaino
- Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Ayumi Sakata
- Department of Clinical Chemistry and Laboratory Medicine, Kyushu University Hospital, Fukuoka, Japan
| | - Katsuya Ogata
- Department of Pharmacy, School of Pharmaceutical Sciences at Fukuoka, International University of Health and Welfare, Okawa, Japan
| | - Hiroshi Shigeto
- Division of Medical Technology, Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Noriko Isobe
- Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Taira Uehara
- Department of Neurology, Neurological Institute, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
- Department of Neurology, School of Medicine, International University of Health and Welfare Narita Hospital, Narita, Japan
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12
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Latreille V, Schiller K, Peter-Derex L, Frauscher B. Does epileptic activity impair sleep-related memory consolidation in epilepsy? A critical and systematic review. J Clin Sleep Med 2022; 18:2481-2495. [PMID: 35866226 PMCID: PMC9516593 DOI: 10.5664/jcsm.10166] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 06/21/2022] [Accepted: 06/23/2022] [Indexed: 11/13/2022]
Abstract
STUDY OBJECTIVES People with epilepsy often complain about disturbed sleep and cognitive impairment. Beyond seizures, the occurrence of interictal epileptic activity during sleep is also increasingly recognized to negatively impact cognitive functioning, including memory processes. The aim of this study was to critically review the effect of interictal epileptic activity on sleep-related memory consolidation. METHODS PubMed and PsychINFO databases were systematically searched to identify experimental studies that investigated sleep-related memory consolidation and the relationships between sleep-related epileptic activity and memory in adults and children with epilepsy. This review also highlights hypotheses regarding the potential pathophysiological mechanisms. RESULTS A total of 261 studies were identified; 27 of these met selection criteria. Only 13 studies prospectively assessed the effect of sleep on memory in epilepsy. Most studies reported no alteration of sleep-related memory consolidation in patients, with either similar retention levels following a period containing sleep (n = 5) or improved memory performance postsleep (n = 4). Two studies in children with epilepsy found impaired sleep-related memory consolidation. Ten studies, of which 6 were in childhood epilepsy syndromes, reported a debilitating effect of sleep-related epileptic activity on memory functioning. CONCLUSIONS Conclusions from existing studies were hampered by small sample sizes, heterogeneous patient groups, and variations in memory assessment techniques. Overall, results to date preclude any definitive conclusions on the alteration of sleep-related memory consolidation in epilepsy. We discuss methodological considerations specific to people with epilepsy and provide suggestions on how to best investigate the relationship between epileptic activity, sleep, and memory consolidation in future studies. CITATION Latreille V, Schiller K, Peter-Derex L, Frauscher B. Does epilepticimpair sleep-related memory consolidation in epilepsy? A critical and systematic review. J Clin Sleep Med. 2022;18(10):2481-2495.
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Affiliation(s)
- Véronique Latreille
- Analytical Neurophysiology Lab, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Katharina Schiller
- Analytical Neurophysiology Lab, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
- Department of Pediatrics, Hospital Group Ostallgaeu-Kaufbeuren, Kaufbeuren, Germany
| | - Laure Peter-Derex
- Analytical Neurophysiology Lab, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
- Center for Sleep Medicine and Respiratory Diseases, Croix-Rousse Hospital, University Hospital of Lyon, Lyon 1 University, France
- Lyon Neuroscience Research Center, INSERM 1028/CNRS 5292, Lyon, France
| | - Birgit Frauscher
- Analytical Neurophysiology Lab, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
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13
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Interictal sleep recordings during presurgical evaluation: Bidirectional perspectives on sleep related network functioning. Rev Neurol (Paris) 2022; 178:703-713. [DOI: 10.1016/j.neurol.2022.03.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 03/08/2022] [Accepted: 03/08/2022] [Indexed: 11/23/2022]
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14
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Oser N, Hubacher M, Nageleisen-Weiss A, van Mierlo P, Huber R, Weber P, Bölsterli BK, Datta AN. 6-year course of sleep homeostasis in a case with epilepsy-aphasia spectrum disorder. Epilepsy Behav Rep 2021; 16:100488. [PMID: 34693247 PMCID: PMC8517280 DOI: 10.1016/j.ebr.2021.100488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 08/27/2021] [Accepted: 09/24/2021] [Indexed: 11/11/2022] Open
Abstract
The overnight change of the slope of SSW as EEG marker for nocturnal regeneration. Reorganization of brain networks can rescue cognitive functions at least partially. Corticosteroids lead to a stabilization of the homeostasis of slope of SSW.
The epilepsy-aphasia spectrum consists of epilepsies with a strong activation of epileptic discharges during non-rapid-eye-movement (NREM) sleep, variable seizure burden and language problems. The homeostatic decrease of slow waves (SW) during NREM sleep (i.e. their amplitude/slope and power) has been related to brain recovery and cognitive function. Epileptic discharges during NREM-sleep were related to an impairment of the decrease of the slope of SW and to cognitive deficits. In this longitudinal case study, we aim to relate this electrophysiological marker, i.e. overnight change of slope of SW, to imaging and behavior. We report a young girl with a fluctuating course in the epilepsy-aphasia spectrum, ranging from the benign end with self-limited childhood epilepsy with centrotemporal spikes (SLECTS) to the severe end with epileptic encephalopathy with continuous spike waves during sleep (CSWS) with two phases of cognitive regression. She was documented over a period of six years including 12 PSGs, six language fMRIs and seven neuropsychological assessments. We longitudinally studied focal and total spike wave index (SWI), detected SW during NREM sleep, calculated their slopes (first and last hour of NREM sleep and overnight change). Deterioration of overnight decrease of the slope of SW was paralleled by the occurrence of the EEG picture of bilateral synchronous electrical status epilepticus during sleep (ESES) and neuropsychological deficits, and this impairment was reversible with resolution of ESES and was accompanied by cognitive improvement. A laterality switch from left to right sided language dominance occurred during recovery from the second regression phase. This might reflect a compensating process. Later, the laterality switched back to the left, possibly facilitated by a low SWI on the left hemisphere. The qualitative analysis of this case supports the view that the longitudinal course of the overnight change of the slope of SW, as an objective, quantitative EEG measure, is related to the course of cognitive function and functional language MR analysis.
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Affiliation(s)
- Nadine Oser
- Department of Pediatric Neurology and Developmental Medicine, University of Basel Children's Hospital, Basel, Switzerland
| | - Martina Hubacher
- Department of Pediatric Neurology and Developmental Medicine, University of Basel Children's Hospital, Basel, Switzerland
| | - Annette Nageleisen-Weiss
- Department of Pediatric Neurology and Developmental Medicine, University of Basel Children's Hospital, Basel, Switzerland
| | - Pieter van Mierlo
- Epilog NV, Ghent, Belgium.,Medical Image and Signal Processing Group, Ghent University, Belgium
| | - Reto Huber
- Department of Pediatric Neurology and Children's Research Center, University Children's Hospital Zurich, University of Zurich, Switzerland.,Child Development Center and Children's Research Center, University Children's Hospital Zurich, University of Zurich, Switzerland.,Department of Child and Adolescent Psychiatry and Psychotherapy, Psychiatric Hospital, University of Zürich, Switzerland
| | - Peter Weber
- Department of Pediatric Neurology and Developmental Medicine, University of Basel Children's Hospital, Basel, Switzerland
| | - Bigna K Bölsterli
- Department of Pediatric Neurology and Children's Research Center, University Children's Hospital Zurich, University of Zurich, Switzerland
| | - Alexandre N Datta
- Department of Pediatric Neurology and Developmental Medicine, University of Basel Children's Hospital, Basel, Switzerland
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15
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Yokosako S, Muraoka N, Watanabe S, Kosugi K, Takayama Y, Iijima K, Kimura Y, Kaneko Y, Sumitomo N, Saito T, Nakagawa E, Iwasaki M. Corpus callosotomy in pediatric patients with non-lesional epileptic encephalopathy with electrical status epilepticus during sleep. Epilepsy Behav Rep 2021; 16:100463. [PMID: 34195590 PMCID: PMC8239855 DOI: 10.1016/j.ebr.2021.100463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/01/2021] [Accepted: 06/02/2021] [Indexed: 11/19/2022] Open
Abstract
Corpus callosotomy (CC) was performed in 3 pediatric patients with refractory epileptic encephalopathy with ESES. IQ was improved after CC with complete resolution of ESES in one patient. Developmental regression ceased after CC with worthwhile seizure reduction and temporary improvement of ESES in 2 patients. Epileptiform discharges disappeared or became lateralized after CC.
Epileptic encephalopathy with electrical status epilepticus during sleep (ESES) is often refractory to medical treatment and leads to poor cognitive outcomes. Corpus callosotomy may be an effective treatment option for drug-resistant ESES with no focal etiology. We retrospectively identified three patients who underwent corpus callosotomy for drug-resistant ESES in our institution. Electroencephalography (EEG) findings and cognitive functions were evaluated before surgery, at 3 months, 6 months, 1 year, and 2 years after surgery. Age at surgery was 6 years 10 months, 7 years 9 months, and 8 years 4 months, respectively. Period between the diagnosis of ESES and surgery ranged from 7 to 25 months. All patients had no obvious structural abnormalities and presented with cognitive decline despite multiple antiseizure medications and steroid therapies. One patient showed complete resolution of ESES and an improvement of intelligence quotient after surgery. Epileptiform EEG was lateralized to one hemisphere after surgery and spike wave index (SWI) was decreased with moderate improvement in development and seizures in the other 2 patients. SWI re-exacerbated from 6 months after surgery, but without subsequent developmental regression in these 2 patients. Corpus callosotomy may become an important treatment option for drug-resistant ESES in patients with no structural abnormalities.
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Affiliation(s)
- Suguru Yokosako
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Norihiro Muraoka
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Shiena Watanabe
- Department of Child Neurology, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Kenzo Kosugi
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Yutaro Takayama
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Keiya Iijima
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Yuiko Kimura
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Yu Kaneko
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Noriko Sumitomo
- Department of Child Neurology, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Takashi Saito
- Department of Child Neurology, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Eiji Nakagawa
- Department of Child Neurology, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
| | - Masaki Iwasaki
- Department of Neurosurgery, National Center Hospital, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan
- Corresponding author.
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16
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Georgopoulou V, Spruyt K, Garganis K, Kosmidis MH. Altered Sleep-Related Consolidation and Neurocognitive Comorbidity in CECTS. Front Hum Neurosci 2021; 15:563807. [PMID: 34163335 PMCID: PMC8215163 DOI: 10.3389/fnhum.2021.563807] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 04/21/2021] [Indexed: 12/03/2022] Open
Abstract
Our aim is to use neurophysiological sleep-related consolidation (SRC) phenomena to identify putative pathophysiological mechanisms in CECTS linked to diffuse neurocognitive deficits. We argue that there are numerous studies on the association between seizure aspects and neurocognitive functioning but not as many on interictal variables and neurocognitive deficits. We suggest two additional foci. First, the interictal presentation in CECTS and second, neuronal oscillations involved in SRC processes. Existing data on mechanisms through which interictal epileptiform spikes (IES) impact upon SRC indicate that they have the potential to: (a) perturb cross-regional coupling of neuronal oscillations, (b) mimic consolidation processes, (c) alter the precision of the spatiotemporal coupling of oscillations, and (d) variably impact upon SRC performance. Sleep spindles merit systematic study in CECTS in order to clarify: (a) the state of the slow oscillations (SOs) with which they coordinate, (b) the precision of slow oscillation-spindle coupling, and (c) whether their developmental trajectories differ from those of healthy children. We subsequently review studies on the associations between IES load during NREM sleep and SRC performance in childhood epilepsy. We then use sleep consolidation neurophysiological processes and their interplay with IES to help clarify the diffuse neurocognitive deficits that have been empirically documented in CECTS. We claim that studying SRC in CECTS will help to clarify pathophysiological mechanisms toward diverse neurocognitive deficits. Future developments could include close links between the fields of epilepsy and sleep, as well as new therapeutic neurostimulation targets. At the clinical level, children diagnosed with CECTS could benefit from close monitoring with respect to epilepsy, sleep and neurocognitive functions.
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Affiliation(s)
- Victoria Georgopoulou
- 2nd Centre for Educational and Counseling Support of Eastern Thessaloniki, Ministry of Education, Thessaloniki, Greece.,Department of Educational and Social Policy, University of Macedonia, Thessaloniki, Greece
| | - Karen Spruyt
- INSERM, Claude Bernard University, School of Medicine, Lyon, France
| | | | - Mary H Kosmidis
- Lab of Cognitive Neuroscience, School of Psychology, Aristotle University of Thessaloniki, Thessaloniki, Greece
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17
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Storz S, Wilhelm I, Critelli H, Feldmann M, Ramirez A, Ramantani G, Huber R, Bölsterli BK. Sleep-dependent memory consolidation in children with self-limited focal epilepsies. Epilepsy Behav 2020; 113:107513. [PMID: 33129045 DOI: 10.1016/j.yebeh.2020.107513] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 09/17/2020] [Accepted: 09/20/2020] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Children with self-limited focal epilepsies of childhood (SLFE) are known to show impaired memory functions, particularly in the verbal domain. Interictal epileptiform discharges (IED) in these epilepsies are more pronounced in nonrapid eye movement (NREM) sleep. Nonrapid eye movement sleep is crucial for consolidation of newly-encoded memories. Therefore, we hypothesize that sleep-dependent memory consolidation is altered in relation to IED in children with SLFE. METHODS We conducted a prospective case-control study. We applied a verbal (word pair) and a visuospatial (two-dimensional [2D] object location) learning task, both previously shown to benefit from sleep in terms of memory consolidation. Learning took place in the evening, and retrieval was tested in the morning after a night of sleep. Electroencephalogram (EEG) was recorded across night. After sleep-stage scoring, the spike-wave index (SWI) was assessed at the beginning and the end of sleep. Fourteen patients with SLFE (age: 5.5 to 11.6 years) were compared with 15 healthy controls (age: 6.8 to 9.1 years) examined in a previous study. RESULTS In contrast to healthy controls (mean: +12.9% recalled word pairs, p = .003, standard deviation (SD) = 12.4%), patients did not show overnight performance gains in the verbal memory task (mean: +6.4% recalled word pairs, p > .05, SD = 17.3) Neither patients nor controls showed significant overnight changes in visuospatial task performance. Spike-wave index was negatively correlated with recall performance in the verbal but not in the visuospatial task. SIGNIFICANCE We found evidence for impaired overnight improvement of performance in children with SLFE in a verbal learning task, with high SWI rates predicting low recall performance. We speculate that spike-waves hamper long-term memory consolidation by interfering with NREM sleep.
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Affiliation(s)
- Sarah Storz
- Children's Research Center, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032 Zurich, Switzerland; Child Development Center, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032 Zurich, Switzerland.
| | - Ines Wilhelm
- Department of Psychiatry and Psychotherapy, Translational Psychiatry Unit (TPU), University of Lübeck, Ratzeburger Allee 160, D-23538 Lübeck, Germany
| | - Hanne Critelli
- Department of Neurology, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032 Zurich, Switzerland
| | - Maria Feldmann
- Children's Research Center, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032 Zurich, Switzerland; Child Development Center, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032 Zurich, Switzerland
| | - Ana Ramirez
- Children's Research Center, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032 Zurich, Switzerland; Child Development Center, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032 Zurich, Switzerland
| | - Georgia Ramantani
- Children's Research Center, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032 Zurich, Switzerland; Department of Neurology, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032 Zurich, Switzerland
| | - Reto Huber
- Children's Research Center, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032 Zurich, Switzerland; Child Development Center, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032 Zurich, Switzerland; Department of Child and Adolescent Psychiatry and Psychotherapy, Psychiatric Hospital University of Zurich, Lenggstrasse 31, 8032 Zurich, Switzerland
| | - Bigna K Bölsterli
- Children's Research Center, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032 Zurich, Switzerland; Department of Neurology, University Children's Hospital Zurich, Steinwiesstrasse 75, 8032 Zurich, Switzerland
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18
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van den Munckhof B, Gefferie SR, van Noort SAM, van Teeseling HC, Schijvens MP, Smit W, Teunissen NW, Plate JDJ, Huiskamp GJM, Leijten FSS, Braun KPJ, Jansen FE, Bölsterli BK. Sleep slow-wave homeostasis and cognitive functioning in children with electrical status epilepticus in sleep. Sleep 2020; 43:5831237. [PMID: 32374855 DOI: 10.1093/sleep/zsaa088] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 03/03/2020] [Indexed: 01/13/2023] Open
Abstract
STUDY OBJECTIVES Encephalopathy with electrical status epilepticus in sleep (ESES) is characterized by non-rapid eye movement (non-REM)-sleep-induced epileptiform activity and acquired cognitive deficits. The synaptic homeostasis hypothesis describes the process of daytime synaptic potentiation balanced by synaptic downscaling in non-REM-sleep and is considered crucial to retain an efficient cortical network. We aimed to study the overnight decline of slow waves, an indirect marker of synaptic downscaling, in patients with ESES and explore whether altered downscaling relates to neurodevelopmental and behavioral problems. METHODS Retrospective study of patients with ESES with at least one whole-night electroencephalogram (EEG) and neuropsychological assessment (NPA) within 4 months. Slow waves in the first and last hour of non-REM-sleep were analyzed. Differences in slow-wave slope (SWS) and overnight slope course between the epileptic focus and non-focus electrodes and relations to neurodevelopment and behavior were analyzed. RESULTS A total of 29 patients with 44 EEG ~ NPA combinations were included. Mean SWS decreased from 357 to 327 µV/s (-8%, p < 0.001) across the night and the overnight decrease was less pronounced in epileptic focus than in non-focus electrodes (-5.6% vs. -8.7%, p = 0.003). We found no relation between SWS and neurodevelopmental test results in cross-sectional and longitudinal analyses. Patients with behavioral problems showed less SWS decline than patients without and the difference was most striking in the epileptic focus (-0.9% vs. -8.8%, p = 0.006). CONCLUSIONS Slow-wave homeostasis-a marker of synaptic homeostasis-is disturbed by epileptiform activity in ESES. Behavioral problems, but not neurodevelopmental test results, were related to severity of this disturbance.
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Affiliation(s)
- Bart van den Munckhof
- Department of Pediatric Neurology, Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Silvano R Gefferie
- Department of Pediatric Neurology, Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Suus A M van Noort
- Department of Pediatric Neurology, Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Heleen C van Teeseling
- Department of Pediatric Neuropsychology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Mischa P Schijvens
- Department of Pediatric Neurology, Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - William Smit
- Department of Clinical Neurophysiology, Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Nico W Teunissen
- Department of Clinical Neurophysiology, Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Joost D J Plate
- Department of Surgery, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Geert Jan M Huiskamp
- Department of Clinical Neurophysiology, Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Frans S S Leijten
- Department of Clinical Neurophysiology, Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Kees P J Braun
- Department of Pediatric Neurology, Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Floor E Jansen
- Department of Pediatric Neurology, Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Bigna K Bölsterli
- Division of Clinical Neurophysiology, Department of Neurology, University Children's Hospital Zurich, Zurich, Switzerland
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19
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Peter‐Derex L, Klimes P, Latreille V, Bouhadoun S, Dubeau F, Frauscher B. Sleep Disruption in Epilepsy: Ictal and Interictal Epileptic Activity Matter. Ann Neurol 2020; 88:907-920. [DOI: 10.1002/ana.25884] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 07/27/2020] [Accepted: 08/16/2020] [Indexed: 12/29/2022]
Affiliation(s)
- Laure Peter‐Derex
- Analytical Neurophysiology Lab Montreal Neurological Institute and Hospital, McGill University Montreal QC Canada
- Center for Sleep Medicine and Respiratory Diseases Lyon University Hospital, Lyon 1 University Lyon France
- Lyon Neuroscience Research Center, CNRS UMR5292 / INSERM, U1028 Lyon France
| | - Petr Klimes
- Analytical Neurophysiology Lab Montreal Neurological Institute and Hospital, McGill University Montreal QC Canada
- Institute of Scientific Instruments, The Czech Academy of Sciences Brno Czech Republic
| | - Véronique Latreille
- Analytical Neurophysiology Lab Montreal Neurological Institute and Hospital, McGill University Montreal QC Canada
| | - Sarah Bouhadoun
- Analytical Neurophysiology Lab Montreal Neurological Institute and Hospital, McGill University Montreal QC Canada
| | - François Dubeau
- Montreal Neurological Institute and Hospital, McGill University Montreal QC Canada
| | - Birgit Frauscher
- Analytical Neurophysiology Lab Montreal Neurological Institute and Hospital, McGill University Montreal QC Canada
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20
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Peiffer A, Brichet M, De Tiège X, Peigneux P, Urbain C. The power of children's sleep - Improved declarative memory consolidation in children compared with adults. Sci Rep 2020; 10:9979. [PMID: 32561803 PMCID: PMC7305149 DOI: 10.1038/s41598-020-66880-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 05/26/2020] [Indexed: 01/22/2023] Open
Abstract
Post-learning slow wave sleep (SWS) is known to support declarative memory consolidation. As SWS is more abundant in young population, we suggested that sleep-dependent memory consolidation processes could occur at a faster pace in school-aged children. After learning new associations between non-objects and their functions, retrieval performance was tested in 30 children (7–12 years) and 34 adults (20–30 years) during an immediate (IR) and a delayed retrieval (DR) session separated by either a Sleep or a Wake condition. Sleep led to stabilized memory retrieval performance only in children, not in adults, whereas no age-related difference was observed after a similar period of wakefulness. Hence, our results suggest more efficient sleep-dependent declarative memory consolidation processes in children compared with adults, an effect potentially ascribed to more abundant and deeper SWS during childhood.
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Affiliation(s)
- Anna Peiffer
- Laboratoire de Cartographie fonctionnelle du Cerveau (LCFC), UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium. .,Neuropsychology and Functional Imaging Research Group (UR2NF), Center for Research in Cognition and Neurosciences (CRCN), UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium.
| | - Maud Brichet
- Laboratoire de Cartographie fonctionnelle du Cerveau (LCFC), UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium.,Neuropsychology and Functional Imaging Research Group (UR2NF), Center for Research in Cognition and Neurosciences (CRCN), UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - Xavier De Tiège
- Laboratoire de Cartographie fonctionnelle du Cerveau (LCFC), UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - Philippe Peigneux
- Neuropsychology and Functional Imaging Research Group (UR2NF), Center for Research in Cognition and Neurosciences (CRCN), UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium
| | - Charline Urbain
- Laboratoire de Cartographie fonctionnelle du Cerveau (LCFC), UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium. .,Neuropsychology and Functional Imaging Research Group (UR2NF), Center for Research in Cognition and Neurosciences (CRCN), UNI - ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Brussels, Belgium.
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21
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Chan SYS. Sleep architecture and homeostasis in children with epilepsy: a neurodevelopmental perspective. Dev Med Child Neurol 2020; 62:426-433. [PMID: 31879946 DOI: 10.1111/dmcn.14437] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/12/2019] [Indexed: 12/14/2022]
Abstract
Although the influence of sleep on epilepsy has long been recognized, this relationship has yet to be fully exploited to benefit patients. The past decade has seen significant advances in understanding paediatric sleep, providing a framework by which to properly evaluate the sleep of children with epilepsy, which itself has been subject to increasing scrutiny. The role of sleep in learning and the potential for interictal discharges to disrupt sleep-related memory consolidation provide a novel perspective for understanding the association of childhood epilepsy with a high rate of intellectual disability. In this review, I outline the evolution of sleep duration, architecture, and homeostasis across childhood, relating this to the development of cognitive functions. I describe how these may be disrupted or preserved in children with epilepsy; in particular, collating data from polysomnography. Finally, I explore how sleep may, in the future, be modulated to improve cognitive outcome in these patients. WHAT THIS PAPER ADDS: Children with epilepsy have less rapid eye movement sleep than controls, but this improves with seizure cessation. Deep or slow-wave sleep is highly conserved in children with epilepsy. Sleep homeostasis may be disrupted either at a local or global level by the presence of interictal epileptiform discharges.
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Affiliation(s)
- Samantha Yuen-Sum Chan
- Clinical Neurosciences Section, Developmental Neurosciences Programme, UCL GOS Institute of Child Health, London, UK
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22
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Gorgoni M, D'Atri A, Scarpelli S, Reda F, De Gennaro L. Sleep electroencephalography and brain maturation: developmental trajectories and the relation with cognitive functioning. Sleep Med 2020; 66:33-50. [PMID: 31786427 DOI: 10.1016/j.sleep.2019.06.025] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 06/24/2019] [Accepted: 06/25/2019] [Indexed: 02/06/2023]
Affiliation(s)
- M Gorgoni
- Department of Psychology, University of Rome "Sapienza", Rome, Italy
| | - A D'Atri
- Department of Psychology, University of Rome "Sapienza", Rome, Italy
| | - S Scarpelli
- Department of Psychology, University of Rome "Sapienza", Rome, Italy
| | - F Reda
- Department of Psychology, University of Rome "Sapienza", Rome, Italy
| | - L De Gennaro
- Department of Psychology, University of Rome "Sapienza", Rome, Italy; IRCCS Santa Lucia Foundation, Rome, Italy.
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23
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The Interface Between Sleep and Epilepsy. CURRENT SLEEP MEDICINE REPORTS 2019. [DOI: 10.1007/s40675-019-00139-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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24
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25
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Colonna A, Smith AB, Smith S, VanDenEshof K, Orgill J, Gringras P, Pal DK. The Effects of Sleep on Emotional Target Detection Performance: A Novel iPad-Based Pediatric Game. Front Psychol 2018; 9:241. [PMID: 29563887 PMCID: PMC5845885 DOI: 10.3389/fpsyg.2018.00241] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 02/13/2018] [Indexed: 12/03/2022] Open
Abstract
Background: Consolidation of learning occurs during sleep but when it is disturbed there may be an adverse impact upon these functions. While research has focused upon how sleep affects cognition in adulthood, the effects of disrupted sleep are likely to impact more heavily on learning among children and adolescents. We aimed to investigate whether a night’s sleep impacts upon executive function compared with an equivalent wakefulness period. We also wanted to know whether restricting sleep would reduce these effects on performance. To investigate this issue in children, we adapted existing research methods to make them more suitable for this population. Methods: Using a cross-over trial design, 22 children aged 7–14 completed an updated but previously validated, continuous performance task (CPT) designed to be appealing to children, containing emotional and neutral targets and presented on an iPad. We measured omission and commission errors, mean and variability of reaction times (RTs) immediately and after a delay spent in the following three ways: 11-h intervals of unrestricted and restricted sleep in the style of a ‘sleepover’ and daytime wakefulness. We examined differences in immediate and delayed testing for each dependent variable. Both sleep nights were spent in a specialist sleep lab where polysomnography data were recorded. Results: While there were no significant main effects of sleep condition, as expected we observed significantly faster and more accurate performance in delayed compared with immediate testing across all conditions for omission errors, RT and variability of RT. Importantly, we saw a significant interaction for commission errors to emotional targets (p = 0.034): while they were comparable across all conditions during immediate testing, for delayed testing there were significantly more errors after wakefulness compared with unrestricted sleep (p = 0.019) and at a trend level for restricted sleep (p = 0.063). Performance improvement after restricted sleep was inversely correlated with sleep opportunity time (p = 0.03), total sleep time (p = 0.01) and total non-REM time (p = 0.005). Conclusion: This tool, designed to be simple to use and appealing to children, revealed a preserving effect of typical and disrupted sleep periods on performance during an emotionally themed target detection task compared with an equivalent wakefulness period.
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Affiliation(s)
- Annalisa Colonna
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Anna B Smith
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Stuart Smith
- Evelina London Children's Hospital, Children's Sleep Medicine, St. Thomas Hospital, London, United Kingdom
| | - Kirandeep VanDenEshof
- Evelina London Children's Hospital, Children's Sleep Medicine, St. Thomas Hospital, London, United Kingdom
| | - Jane Orgill
- Evelina London Children's Hospital, Children's Sleep Medicine, St. Thomas Hospital, London, United Kingdom
| | - Paul Gringras
- Evelina London Children's Hospital, Children's Sleep Medicine, St. Thomas Hospital, London, United Kingdom
| | - Deb K Pal
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.,Evelina London Children's Hospital, Children's Sleep Medicine, St. Thomas Hospital, London, United Kingdom
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26
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Bölsterli BK, Gardella E, Pavlidis E, Wehrle FM, Tassinari CA, Huber R, Rubboli G. Remission of encephalopathy with status epilepticus (ESES) during sleep renormalizes regulation of slow wave sleep. Epilepsia 2017; 58:1892-1901. [DOI: 10.1111/epi.13910] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/29/2017] [Indexed: 10/18/2022]
Affiliation(s)
- Bigna K. Bölsterli
- Division of Clinical Neurophysiology; University Children's Hospital Zurich; Zurich Switzerland
- Children's Research Center; University Children's Hospital Zurich; Zurich Switzerland
| | - Elena Gardella
- Department of Clinical Neurophysiology; Danish Epilepsy Center; Dianalund Denmark
- University of Southern Denmark; Odense Denmark
| | - Elena Pavlidis
- Danish Epilepsy Center; Dianalund Denmark
- Child Neuropsychiatry Unit; Department of Neuroscience; University of Parma; Parma Italy
| | - Flavia M. Wehrle
- Children's Research Center; University Children's Hospital Zurich; Zurich Switzerland
- Child Development Center; University Children's Hospital Zurich; Zurich Switzerland
| | | | - Reto Huber
- Children's Research Center; University Children's Hospital Zurich; Zurich Switzerland
- Child Development Center; University Children's Hospital Zurich; Zurich Switzerland
- Department of Child and Adolescent Psychiatry and Psychotherapy; Psychiatric Hospital; University of Zurich; Zurich Switzerland
| | - Guido Rubboli
- Danish Epilepsy Center; Filadelfia/University of Copenhagen; Copenhagen Denmark
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27
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Chan S, Pressler R, Boyd SG, Baldeweg T, Cross JH. Does sleep benefit memory consolidation in children with focal epilepsy? Epilepsia 2017; 58:456-466. [DOI: 10.1111/epi.13668] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/20/2016] [Indexed: 02/05/2023]
Affiliation(s)
- Samantha Chan
- Developmental Neurosciences Programme; UCL Great Ormond Street Institute of Child Health; London United Kingdom
- Great Ormond Street Hospital NHS Trust; London United Kingdom
| | - Ronit Pressler
- Developmental Neurosciences Programme; UCL Great Ormond Street Institute of Child Health; London United Kingdom
- Great Ormond Street Hospital NHS Trust; London United Kingdom
| | - Stewart G. Boyd
- Great Ormond Street Hospital NHS Trust; London United Kingdom
| | - Torsten Baldeweg
- Developmental Neurosciences Programme; UCL Great Ormond Street Institute of Child Health; London United Kingdom
| | - J. Helen Cross
- Developmental Neurosciences Programme; UCL Great Ormond Street Institute of Child Health; London United Kingdom
- Great Ormond Street Hospital NHS Trust; London United Kingdom
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28
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Systad S, Bjørnvold M, Markhus R, Lyster SAH. Watch the language! Language and linguistic-cognitive abilities in children with nocturnal epileptiform activity. Epilepsy Behav 2017; 66:10-18. [PMID: 27984701 DOI: 10.1016/j.yebeh.2016.09.041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 09/23/2016] [Accepted: 09/23/2016] [Indexed: 11/25/2022]
Abstract
We studied the language and linguistic-cognitive abilities of a group of children with nocturnal epileptiform activity (NEA; N=33) who were hospitalized at a tertiary epilepsy hospital. The children were compared with two groups: one age- and gender-matched group (N=33) and one group matched on language ability (vocabulary) and gender (N=66). We also examined how NEA-related variables affected language abilities. Overall, the children with NEA showed delayed language abilities and a trend for specific difficulties with phonology and naming speed. We did not find firm evidence that the amount of NEA, the use of antiepileptic drugs (AEDs), and the lateralization and localization of NEA had an effect on language. However, we found that children with right-lateralized epileptiform activity seemed to have specific difficulties with naming speed. Additionally, our results indicated that NEA located in the centrotemporal areas particularly affected phonology and orthographic skills.
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Affiliation(s)
| | - Marit Bjørnvold
- Department of Refractory Epilepsy- SSE, Oslo University Hospital, Norway
| | - Rune Markhus
- Department of Refractory Epilepsy- SSE, Oslo University Hospital, Norway
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29
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Atherton KE, Nobre AC, Lazar AS, Wulff K, Whittaker RG, Dhawan V, Lazar ZI, Zeman AZ, Butler CR. Slow wave sleep and accelerated forgetting. Cortex 2016; 84:80-89. [PMID: 27710778 PMCID: PMC5084685 DOI: 10.1016/j.cortex.2016.08.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 07/04/2016] [Accepted: 08/29/2016] [Indexed: 12/12/2022]
Abstract
We investigated whether the benefit of slow wave sleep (SWS) for memory consolidation typically observed in healthy individuals is disrupted in people with accelerated long-term forgetting (ALF) due to epilepsy. SWS is thought to play an active role in declarative memory in healthy individuals and, furthermore, electrographic epileptiform activity is often more prevalent during SWS than during wakefulness or other sleep stages. We studied the relationship between SWS and the benefit of sleep for memory retention using a word-pair associates task. In both the ALF and the healthy control groups, sleep conferred a memory benefit. However, the relationship between the amount of SWS and sleep-related memory benefits differed significantly between the groups. In healthy participants, the amount of SWS correlated positively with sleep-related memory benefits. In stark contrast, the more SWS, the smaller the sleep-related memory benefit in the ALF group. Therefore, contrary to its role in healthy people, SWS-associated brain activity appears to be deleterious for memory in patients with ALF.
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Affiliation(s)
- Kathryn E Atherton
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Anna C Nobre
- Oxford Centre for Human Brain Activity, University of Oxford, Oxford, UK
| | - Alpar S Lazar
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, UK
| | - Katharina Wulff
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | | | - Vandana Dhawan
- Institute of Neuroscience, Newcastle University, Newcastle, UK
| | - Zsolt I Lazar
- Department of Physics, Babes-Bolyai University, Cluj-Napoca, Romania
| | - Adam Z Zeman
- Cognitive and Behavioural Neurology, Peninsular Medical School, University of Exeter, UK
| | - Christopher R Butler
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
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30
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Martin R, Cirino P, Hiscock M, Schultz R, Collins R, Chapieski L. Risks and benefits of epilepsy surgery in a pediatric population: Consequences for memory and academic skills. Epilepsy Behav 2016; 62:189-96. [PMID: 27494354 DOI: 10.1016/j.yebeh.2016.06.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 06/13/2016] [Accepted: 06/23/2016] [Indexed: 10/21/2022]
Abstract
We examined benefits and risks for memory and academic functioning associated with epilepsy surgery in a pediatric population. A total of 46 patients with intractable seizures and a single seizure focus were divided into four groups according to focus localization: right temporal, left temporal, frontal, and parietal/occipital region. Pre- and postsurgery performance measures were compared across groups and with a fifth group of patients that had intractable seizures but did not undergo surgery. Both groups with temporal lobe epilepsy showed significant declines in memory test scores, while performance of the group with frontal lobe epilepsy improved. These changes were mirrored in parental reports of everyday memory. Consistent with other pediatric studies, no lateralized material-specific declines in the groups with temporal lobe epilepsy were found. When memory improved, the improvement was associated with decreases in seizure frequency and the number of anticonvulsant medications. Presurgical performance was the best predictor of declines in memory test performance. Deterioration of academic test scores in the group that did not have surgery exemplified a potential risk of living with seizures and antiepilepsy medication.
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Affiliation(s)
- Rebecca Martin
- Department of Psychology, University of Houston, Houston, TX, USA.
| | - Paul Cirino
- Department of Psychology, University of Houston, Houston, TX, USA.
| | - Merrill Hiscock
- Department of Psychology, University of Houston, Houston, TX, USA; Center for Neuro-Engineering and Cognitive Science, University of Houston, Houston, TX, USA.
| | - Rebecca Schultz
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA.
| | - Robert Collins
- Neurology Care Line, Michael E. DeBakey VA Medical Center, Houston, TX, USA; Department of Neurology, Baylor College of Medicine, Houston, TX, USA.
| | - Lynn Chapieski
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA.
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31
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Glennon JM, Weiss-Croft L, Harrison S, Cross JH, Boyd SG, Baldeweg T. Interictal epileptiform discharges have an independent association with cognitive impairment in children with lesional epilepsy. Epilepsia 2016; 57:1436-42. [PMID: 27503785 DOI: 10.1111/epi.13479] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2016] [Indexed: 02/03/2023]
Abstract
OBJECTIVES The relative contribution of interictal epileptiform discharges (IEDs) to cognitive dysfunction in comparison with the underlying brain pathology is not yet understood in children with lesional focal epilepsy. METHODS The current study investigated the association of IEDs with intellectual functioning in 103 children with medication-resistant focal epilepsy. Hierarchical multiple regression analyses were used to determine the independent contribution of IED features on intellectual functioning, after controlling for effects of lesional pathology, epilepsy duration, and medication. Exploratory analyses were conducted for language and memory scores as well as academic skills available in a subset of participants. RESULTS The results reveal that IEDs have a negative association with IQ with independent, additive effects documented for frequent and bilaterally distributed IEDs as well as discharge enhancement in sleep. Left-lateralized IEDs had a prominent effect on verbal intelligence, in excess of the influence of left-sided brain pathology. These effects extended to other cognitive functions, most prominently for sleep-enhanced IEDs to be associated with deficits in expressive and receptive language, reading, spelling and numerical skills. SIGNIFICANCE Overall, IED effects on cognition were of a magnitude similar to lesional influences or drug effects (topiramate use). This study demonstrates an association between IEDs and cognitive dysfunction, independent of the underlying focal brain pathology.
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Affiliation(s)
- Jennifer M Glennon
- Developmental Neurosciences Programme, UCL Institute of Child Health, London, United Kingdom
| | - Louise Weiss-Croft
- Developmental Neurosciences Programme, UCL Institute of Child Health, London, United Kingdom.,Great Ormond Street Hospital NHS Trust, London, United Kingdom
| | - Sue Harrison
- Great Ormond Street Hospital NHS Trust, London, United Kingdom
| | - J Helen Cross
- Developmental Neurosciences Programme, UCL Institute of Child Health, London, United Kingdom.,Great Ormond Street Hospital NHS Trust, London, United Kingdom
| | - Stewart G Boyd
- Great Ormond Street Hospital NHS Trust, London, United Kingdom
| | - Torsten Baldeweg
- Developmental Neurosciences Programme, UCL Institute of Child Health, London, United Kingdom.,Great Ormond Street Hospital NHS Trust, London, United Kingdom
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32
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Urbain C, De Tiège X, Op De Beeck M, Bourguignon M, Wens V, Verheulpen D, Van Bogaert P, Peigneux P. Sleep in children triggers rapid reorganization of memory-related brain processes. Neuroimage 2016; 134:213-222. [DOI: 10.1016/j.neuroimage.2016.03.055] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 03/21/2016] [Indexed: 10/22/2022] Open
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33
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Sarkis RA, Alam J, Pavlova MK, Dworetzky BA, Pennell PB, Stickgold R, Bubrick EJ. Sleep-dependent memory consolidation in the epilepsy monitoring unit: A pilot study. Clin Neurophysiol 2016; 127:2785-2790. [PMID: 27417054 DOI: 10.1016/j.clinph.2016.05.275] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 05/20/2016] [Accepted: 05/23/2016] [Indexed: 10/21/2022]
Abstract
OBJECTIVE We sought to examine whether patients with focal epilepsy exhibit sleep dependent memory consolidation, whether memory retention rates correlated with particular aspects of sleep physiology, and how the process was affected by seizures. METHODS We prospectively recruited patients with focal epilepsy and assessed declarative memory using a task consisting of 15 pairs of colored pictures on a 5×6 grid. Patients were tested 12h after training, once after 12h of wakefulness and once after 12h that included sleep. EMG chin electrodes were placed to enable sleep scoring. The number and density of sleep spindles were assessed using a wavelet-based algorithm. RESULTS Eleven patients were analyzed age 21-56years. The percentage memory retention over 12h of wakefulness was 62.7% and over 12h which included sleep 83.6% (p=0.04). Performance on overnight testing correlated with the duration of slow wave sleep (SWS) (r=+0.63, p<0.05). Three patients had seizures during the day, and 3 had nocturnal seizures. Day-time seizures did not affect retention rates, while those patients who had night time seizures had a drop in retention from an average of 92% to 60.5%. CONCLUSIONS There is evidence of sleep dependent memory consolidation in patients with epilepsy which mostly correlates with the amount of SWS. Our preliminary findings suggest that nocturnal seizures likely disrupt sleep dependent memory consolidation. SIGNIFICANCE Findings highlight the importance of SWS in sleep dependent memory consolidation and the adverse impact of nocturnal seizures on this process.
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Affiliation(s)
- Rani A Sarkis
- Department of Neurology, Edward B. Bromfield Epilepsy Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
| | - Javad Alam
- Department of Neurology, Edward B. Bromfield Epilepsy Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Milena K Pavlova
- Department of Neurology, Edward B. Bromfield Epilepsy Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Barbara A Dworetzky
- Department of Neurology, Edward B. Bromfield Epilepsy Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Page B Pennell
- Department of Neurology, Edward B. Bromfield Epilepsy Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Robert Stickgold
- Department of Psychiatry, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Ellen J Bubrick
- Department of Neurology, Edward B. Bromfield Epilepsy Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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Vega YH, Smith A, Cockerill H, Tang S, Agirre-Arrizubieta Z, Goyal S, Pina M, Akman CI, Jolleff N, McGinnity C, Gomez K, Gupta R, Hughes E, Jackman J, McCormick D, Oren C, Scott D, Taylor J, Trounce J, Clarke T, Kugler S, Mandelbaum DE, McGoldrick P, Wolf S, Strug LJ, Pal DK. Risk factors for reading disability in families with rolandic epilepsy. Epilepsy Behav 2015; 53:174-9. [PMID: 26580214 PMCID: PMC4719157 DOI: 10.1016/j.yebeh.2015.10.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 10/14/2015] [Accepted: 10/16/2015] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The high prevalence and impact of neurodevelopmental comorbidities in childhood epilepsy are now well known, as are the increased risks and familial aggregation of reading disability (RD) and speech sound disorder (SSD) in rolandic epilepsy (RE). The risk factors for RD in the general population include male sex, SSD, and ADHD, but it is not known if these are the same in RE or whether there is a contributory role of seizure and treatment-related variables. METHODS An observational study of 108 probands with RE (age range: 3.6-22 years) and their 159 siblings (age range: 1-29 years; 83 with EEG data) were singly ascertained in the US or UK through a proband affected by RE. We used a nested case-control design, multiple logistic regression, and generalized estimating equations to test the hypothesis of an association between RD and seizure variables or antiepileptic drug treatment in RE; we also assessed an association between EEG focal sharp waves and RD in siblings. RESULTS Reading disability was reported in 42% of probands and 22% of siblings. Among probands, RD was strongly associated with a history of SSD (OR: 9.64, 95% CI: 2.45-37.21), ADHD symptoms (OR: 10.31, 95% CI: 2.15-49.44), and male sex (OR: 3.62, 95% CI: 1.11-11.75) but not with seizure or treatment variables. Among siblings, RD was independently associated only with SSD (OR: 4.30, 95% CI: 1.42-13.0) and not with the presence of interictal EEG focal sharp waves. SIGNIFICANCE The principal risk factors for RD in RE are SSD, ADHD, and male sex, the same risk factors as for RD without epilepsy. Seizure or treatment variables do not appear to be important risk factors for RD in probands with RE, and there was no evidence to support interictal EEG focal sharp waves as a risk factor for RD in siblings. Future studies should focus on the precise neuropsychological characterization of RD in families with RE and on the effectiveness of standard oral-language and reading interventions.
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Affiliation(s)
| | | | | | - Shan Tang
- King’s College London, UK,King’s Health Partners, London, UK
| | | | | | | | - Cigdem I Akman
- Department of Neurology, Columbia University, New York, USA
| | - Nicola Jolleff
- East Kent Hospitals University NHS Foundation Trust, Canterbury, UK
| | | | | | | | | | | | | | | | | | | | | | - Tara Clarke
- Department of Epidemiology, Columbia University, New York, USA
| | - Steven Kugler
- Children’s Hospital of Philadelphia and University of Pennsylvania School of Medicine, PA, USA
| | - David E Mandelbaum
- Hasbro Children’s Hospital and the Warren Alpert Medical School of Brown University, Providence, RI, USA
| | | | | | - Lisa J Strug
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto; Canada,Dalla Lana School of Public Health, University of Toronto, Canada
| | - Deb K Pal
- King's College London, UK; King's Health Partners, London, UK.
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Höller Y, Trinka E. Is There a Relation between EEG-Slow Waves and Memory Dysfunction in Epilepsy? A Critical Appraisal. Front Hum Neurosci 2015; 9:341. [PMID: 26124717 PMCID: PMC4463866 DOI: 10.3389/fnhum.2015.00341] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 05/28/2015] [Indexed: 12/12/2022] Open
Abstract
Is there a relationship between peri-ictal slow waves, loss of consciousness, memory, and slow-wave sleep, in patients with different forms of epilepsy? We hypothesize that mechanisms, which result in peri-ictal slow-wave activity as detected by the electroencephalogram, could negatively affect memory processes. Slow waves (≤4 Hz) can be found in seizures with impairment of consciousness and also occur in focal seizures without impairment of consciousness but with inhibited access to memory functions. Peri-ictal slow waves are regarded as dysfunctional and are probably caused by mechanisms, which are essential to disturb the consolidation of memory entries in these patients. This is in strong contrast to physiological slow-wave activity during deep sleep, which is thought to group memory-consolidating fast oscillatory activity. In patients with epilepsy, slow waves may not only correlate with the peri-ictal clouding of consciousness, but could be the epiphenomenon of mechanisms, which interfere with normal brain function in a wider range. These mechanisms may have transient impacts on memory, such as temporary inhibition of memory systems, altered patterns of hippocampal-neocortical interactions during slow-wave sleep, or disturbed cross-frequency coupling of slow and fast oscillations. In addition, repeated tonic-clonic seizures over the years in uncontrolled chronic epilepsy may cause a progressive cognitive decline. This hypothesis can only be assessed in long-term prospective studies. These studies could disentangle the reversible short-term impacts of seizures, and the impacts of chronic uncontrolled seizures. Chronic uncontrolled seizures lead to irreversible memory impairment. By contrast, short-term impacts do not necessarily lead to a progressive cognitive decline but result in significantly impaired peri-ictal memory performance.
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Affiliation(s)
- Yvonne Höller
- Department of Neurology, Christian Doppler Medical Centre and Centre for Cognitive Neuroscience, Paracelsus Medical University, Salzburg, Austria
| | - Eugen Trinka
- Department of Neurology, Christian Doppler Medical Centre and Centre for Cognitive Neuroscience, Paracelsus Medical University, Salzburg, Austria
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