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Kokkinos V, Seimenis I. Concordance of verbal memory and language fMRI lateralization in people with epilepsy. J Neuroimaging 2024; 34:95-107. [PMID: 37968766 DOI: 10.1111/jon.13171] [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: 09/17/2023] [Revised: 10/29/2023] [Accepted: 11/01/2023] [Indexed: 11/17/2023] Open
Abstract
BACKGROUND AND PURPOSE This work investigates verbal memory functional MRI (fMRI) versus language fMRI in terms of lateralization, and assesses the validity of performing word recognition during the functional scan. METHODS Thirty patients with a diagnosis of epilepsy underwent verbal memory, visuospatial memory, and language fMRI. We used word encoding, word recognition, image encoding, and image recognition memory tasks, and semantic description, reading comprehension, and listening comprehension language tasks. We used three common lateralization metrics: network spatial distribution, maximum statistical value, and laterality index (LI). RESULTS Lateralization of signal spatial distribution resulted in poor similarity between verbal memory and language fMRI tasks. Signal maximum lateralization showed significant (>.8) but not perfect (1) similarity. Word encoding LI showed significant correlation only with listening comprehension LI (p = .016). Word recognition LI was significantly correlated with expressive language semantic description LI (p = .024) and receptive language reading and listening comprehension LIs (p = .015 and p = .019, respectively). There was no correlation between LIs of the visuospatial tasks and LIs of the language tasks. CONCLUSIONS Our results support the association between language and verbal memory lateralization, optimally determined by LI quantification, and the introduction of quantitative means for language fMRI interpretation in clinical settings where verbal memory lateralization is imperative.
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Affiliation(s)
- Vasileios Kokkinos
- Comprehensive Epilepsy Center, Northwestern Memorial Hospital, Chicago, Illinois, USA
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Department of Medicine, School of Health Sciences, Democritus University of Thrace, Alexandroupoli, Greece
| | - Ioannis Seimenis
- Department of Medicine, School of Health Sciences, Democritus University of Thrace, Alexandroupoli, Greece
- Medical School, National and Kapodistrian University of Athens, Athens, Greece
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Hinds W, Modi S, Ankeeta A, Sperling MR, Pustina D, Tracy JI. Pre-surgical features of intrinsic brain networks predict single and joint epilepsy surgery outcomes. Neuroimage Clin 2023; 38:103387. [PMID: 37023491 PMCID: PMC10122017 DOI: 10.1016/j.nicl.2023.103387] [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: 12/15/2022] [Revised: 03/02/2023] [Accepted: 03/24/2023] [Indexed: 03/31/2023]
Abstract
Despite the effectiveness of surgical interventions for the treatment of intractable focal temporal lobe epilepsy (TLE), the substrates that support good outcomes are poorly understood. While algorithms have been developed for the prediction of either seizure or cognitive/psychiatric outcomes alone, no study has reported on the functional and structural architecture that supports joint outcomes. We measured key aspects of pre-surgical whole brain functional/structural network architecture and evaluated their ability to predict post-operative seizure control in combination with cognitive/psychiatric outcomes. Pre-surgically, we identified the intrinsic connectivity networks (ICNs) unique to each person through independent component analysis (ICA), and computed: (1) the spatial-temporal match between each person's ICA components and established, canonical ICNs, (2) the connectivity strength within each identified person-specific ICN, (3) the gray matter (GM) volume underlying the person-specific ICNs, and (4) the amount of variance not explained by the canonical ICNs for each person. Post-surgical seizure control and reliable change indices of change (for language [naming, phonemic fluency], verbal episodic memory, and depression) served as binary outcome responses in random forest (RF) models. The above functional and structural measures served as input predictors. Our empirically derived ICN-based measures customized to the individual showed that good joint seizure and cognitive/psychiatric outcomes depended upon higher levels of brain reserve (GM volume) in specific networks. In contrast, singular outcomes relied on systematic, idiosyncratic variance in the case of seizure control, and the weakened pre-surgical presence of functional ICNs that encompassed the ictal temporal lobe in the case of cognitive/psychiatric outcomes. Our data made clear that the ICNs differed in their propensity to provide reserve for adaptive outcomes, with some providing structural (brain), and others functional (cognitive) reserve. Our customized methodology demonstrated that when substantial unique, patient-specific ICNs are present prior to surgery there is a reliable association with poor post-surgical seizure control. These ICNs are idiosyncratic in that they did not match the canonical, normative ICNs and, therefore, could not be defined functionally, with their location likely varying by patient. This important finding suggested the level of highly individualized ICN's in the epileptic brain may signal the emergence of epileptogenic activity after surgery.
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Affiliation(s)
- Walter Hinds
- Thomas Jefferson University, Department of Neurology, and Vicky and Jack Farber Institute for Neuroscience, USA
| | - Shilpi Modi
- Thomas Jefferson University, Department of Neurology, and Vicky and Jack Farber Institute for Neuroscience, USA
| | - Ankeeta Ankeeta
- Thomas Jefferson University, Department of Neurology, and Vicky and Jack Farber Institute for Neuroscience, USA
| | - Michael R Sperling
- Thomas Jefferson University, Department of Neurology, and Vicky and Jack Farber Institute for Neuroscience, USA
| | | | - Joseph I Tracy
- Thomas Jefferson University, Department of Neurology, and Vicky and Jack Farber Institute for Neuroscience, USA.
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Fleury M, Buck S, Binding LP, Caciagli L, Vos SB, Winston GP, Thompson P, Koepp MJ, Duncan JS, Sidhu MK. Episodic memory network connectivity in temporal lobe epilepsy. Epilepsia 2022; 63:2597-2622. [PMID: 35848050 PMCID: PMC9804196 DOI: 10.1111/epi.17370] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 07/14/2022] [Accepted: 07/15/2022] [Indexed: 01/07/2023]
Abstract
OBJECTIVE Temporal lobe epilepsy (TLE) affects brain networks and is associated with impairment of episodic memory. Temporal and extratemporal reorganization of memory functions is described in functional magnetic resonance imaging (fMRI) studies. Functional reorganizations have been shown at the local activation level, but network-level alterations have been underinvestigated. We aim to investigate the functional anatomy of memory networks using memory fMRI and determine how this relates to memory function in TLE. METHODS Ninety patients with unilateral TLE (43 left) and 29 controls performed a memory-encoding fMRI paradigm of faces and words with subsequent out-of-scanner recognition test. Subsequent memory event-related contrasts of words and faces remembered were generated. Psychophysiological interaction analysis investigated task-associated changes in functional connectivity seeding from the mesial temporal lobes (MTLs). Correlations between changes in functional connectivity and clinical memory scores, epilepsy duration, age at epilepsy onset, and seizure frequency were investigated, and between connectivity supportive of better memory and disease burden. Connectivity differences between controls and TLE, and between TLE with and without hippocampal sclerosis, were explored using these confounds as regressors of no interest. RESULTS Compared to controls, TLE patients showed widespread decreased connectivity between bilateral MTLs and frontal lobes, and increased local connectivity between the anterior MTLs bilaterally. Increased intrinsic connectivity within the bilateral MTLs correlated with better out-of-scanner memory performance in both left and right TLE. Longer epilepsy duration and higher seizure frequency were associated with decreased connectivity between bilateral MTLs and left/right orbitofrontal cortex (OFC) and insula, connections supportive of memory functions. TLE due to hippocampal sclerosis was associated with greater connectivity disruption within the MTL and extratemporally. SIGNIFICANCE Connectivity analyses showed that TLE is associated with temporal and extratemporal memory network reorganization. Increased bilateral functional connectivity within the MTL and connectivity to OFC and insula are efficient, and are disrupted by greater disease burden.
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Affiliation(s)
- Marine Fleury
- Department of Clinical and Experimental EpilepsyUniversity College London Queen Square Institute of NeurologyLondonUK
- MRI UnitEpilepsy SocietyBuckinghamshireUK
| | - Sarah Buck
- Department of Clinical and Experimental EpilepsyUniversity College London Queen Square Institute of NeurologyLondonUK
- MRI UnitEpilepsy SocietyBuckinghamshireUK
| | - Lawrence P. Binding
- Department of Clinical and Experimental EpilepsyUniversity College London Queen Square Institute of NeurologyLondonUK
- MRI UnitEpilepsy SocietyBuckinghamshireUK
- Department of Computer Science, Centre for Medical Image ComputingUniversity College LondonLondonUK
| | - Lorenzo Caciagli
- Department of Clinical and Experimental EpilepsyUniversity College London Queen Square Institute of NeurologyLondonUK
- MRI UnitEpilepsy SocietyBuckinghamshireUK
- Department of BioengineeringUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Sjoerd B. Vos
- Department of Clinical and Experimental EpilepsyUniversity College London Queen Square Institute of NeurologyLondonUK
- MRI UnitEpilepsy SocietyBuckinghamshireUK
- Neuroradiological Academic Unit, University College London Queen Square Institute of NeurologyUniversity College LondonLondonUK
| | - Gavin P. Winston
- Department of Clinical and Experimental EpilepsyUniversity College London Queen Square Institute of NeurologyLondonUK
- MRI UnitEpilepsy SocietyBuckinghamshireUK
- Division of Neurology, Department of MedicineQueen's UniversityKingstonOntarioCanada
| | - Pamela J. Thompson
- Department of Clinical and Experimental EpilepsyUniversity College London Queen Square Institute of NeurologyLondonUK
- MRI UnitEpilepsy SocietyBuckinghamshireUK
| | - Matthias J. Koepp
- Department of Clinical and Experimental EpilepsyUniversity College London Queen Square Institute of NeurologyLondonUK
- MRI UnitEpilepsy SocietyBuckinghamshireUK
| | - John S. Duncan
- Department of Clinical and Experimental EpilepsyUniversity College London Queen Square Institute of NeurologyLondonUK
- MRI UnitEpilepsy SocietyBuckinghamshireUK
| | - Meneka K. Sidhu
- Department of Clinical and Experimental EpilepsyUniversity College London Queen Square Institute of NeurologyLondonUK
- MRI UnitEpilepsy SocietyBuckinghamshireUK
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Rayner G, Antoniou M, Jackson G, Tailby C. Compromised future thinking: another cognitive cost of temporal lobe epilepsy. Brain Commun 2022; 4:fcac062. [PMID: 35356031 PMCID: PMC8963290 DOI: 10.1093/braincomms/fcac062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 01/31/2022] [Accepted: 03/15/2022] [Indexed: 12/02/2022] Open
Abstract
The ability to mentally travel forward through time allows humans to envisage a diverse array of possible events taking place in the future, helping us to choose which pathway to take in life. In epilepsy, we assume that patients use this cognitive ability when deciding between various treatment options, but this assumption has not been robustly tested. The temporal lobes are key contributors to this ‘future thinking’ and its building blocks include cognitive functions commonly impaired in temporal lobe epilepsy such as memory and language, giving rise to a hypothesis that ‘future thinking’ is impaired in this patient cohort. Participants were 68 adults: 37 with neurosurgically-naïve, unilateral temporal lobe epilepsy (51% right lateralized) and 31 healthy controls of similar age, sex and intellectual ability to the participants with epilepsy. Future thinking was measured using an imagined experiences task validated in other neurological populations. Tools well-established in temporal lobe epilepsy were used to measure potential cognitive correlates of future thinking. Analysis of variance revealed significantly impoverished future thinking in both left and right temporal lobe epilepsy relative to controls (P = 0.001, ηp2=0.206), with no difference between temporal lobe epilepsy groups (P > 0.05). Future thinking deficits in left temporal lobe epilepsy were paralleled by deficits in scene construction, whereas impoverished future thinking in right temporal lobe epilepsy occurred in the setting of intact scene construction. Deficits in future thinking were associated with reductions in lexical access and episodic autobiographic memory in both epilepsy groups. In sum, future thinking is compromised in both left and right temporal lobe epilepsy. The deficit in left temporal lobe epilepsy is largely explainable by dysfunction in verbal cognitive processes including scene construction. While the basis of the deficits observed with right temporal foci shares features with that of left temporal lobe epilepsy, their intact scene construction raises questions about the role of the left and right temporal lobes in future thinking and scene construction and the relationship between these two constructs, including whether right temporal lobe might play a specific role in future thinking in terms of creative processing. Clinicians should take impaired future thinking into account when counselling temporal lobe epilepsy patients about various treatment options, as they may struggle to vividly imagine what different outcomes might mean for their future selves.
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Affiliation(s)
- Genevieve Rayner
- Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia
- Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, Victoria, Australia
- Department of Clinical Neuropsychology, Austin Health, Heidelberg, Victoria, Australia
| | - Mariana Antoniou
- Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia
| | - Graeme Jackson
- Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia
| | - Chris Tailby
- Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia
- Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, Victoria, Australia
- Department of Clinical Neuropsychology, Austin Health, Heidelberg, Victoria, Australia
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Banjac S, Roger E, Cousin E, Mosca C, Minotti L, Krainik A, Kahane P, Baciu M. Mapping of Language-and-Memory Networks in Patients With Temporal Lobe Epilepsy by Using the GE2REC Protocol. Front Hum Neurosci 2022; 15:752138. [PMID: 35069148 PMCID: PMC8772037 DOI: 10.3389/fnhum.2021.752138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 12/13/2021] [Indexed: 11/17/2022] Open
Abstract
Preoperative mapping of language and declarative memory functions in temporal lobe epilepsy (TLE) patients is essential since they frequently encounter deterioration of these functions and show variable degrees of cerebral reorganization. Due to growing evidence on language and declarative memory interdependence at a neural and neuropsychological level, we propose the GE2REC protocol for interactive language-and-memory network (LMN) mapping. GE2REC consists of three inter-related tasks, sentence generation with implicit encoding (GE) and two recollection (2REC) memory tasks: recognition and recall. This protocol has previously been validated in healthy participants, and in this study, we showed that it also maps the LMN in the left TLE (N = 18). Compared to healthy controls (N = 19), left TLE (LTLE) showed widespread inter- and intra-hemispheric reorganization of the LMN through reduced activity of regions engaged in the integration and the coordination of this meta-network. We also illustrated how this protocol could be implemented in clinical practice individually by presenting two case studies of LTLE patients who underwent efficient surgery and became seizure-free but showed different cognitive outcomes. This protocol can be advantageous for clinical practice because it (a) is short and easy to perform; (b) allows brain mapping of essential cognitive functions, even at an individual level; (c) engages language-and-memory interaction allowing to evaluate the integrative processes within the LMN; (d) provides a more comprehensive assessment by including both verbal and visual modalities, as well as various language and memory processes. Based on the available postsurgical data, we presented preliminary results obtained with this protocol in LTLE patients that could potentially inform the clinical practice. This implies the necessity to further validate the potential of GE2REC for neurosurgical planning, along with two directions, guiding resection and describing LMN neuroplasticity at an individual level.
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Affiliation(s)
- Sonja Banjac
- Université Grenoble Alpes, CNRS LPNC UMR 5105, Grenoble, France
| | - Elise Roger
- Université Grenoble Alpes, CNRS LPNC UMR 5105, Grenoble, France
| | - Emilie Cousin
- Université Grenoble Alpes, CNRS LPNC UMR 5105, Grenoble, France
- Université Grenoble Alpes, UMS IRMaGe CHU Grenoble, Grenoble, France
| | - Chrystèle Mosca
- Université Grenoble Alpes, Grenoble Institute of Neuroscience ‘Synchronisation et modulation des réseaux neuronaux dans l’épilepsie’ & Neurology Department, Grenoble, France
| | - Lorella Minotti
- Université Grenoble Alpes, Grenoble Institute of Neuroscience ‘Synchronisation et modulation des réseaux neuronaux dans l’épilepsie’ & Neurology Department, Grenoble, France
| | - Alexandre Krainik
- Université Grenoble Alpes, UMS IRMaGe CHU Grenoble, Grenoble, France
| | - Philippe Kahane
- Université Grenoble Alpes, Grenoble Institute of Neuroscience ‘Synchronisation et modulation des réseaux neuronaux dans l’épilepsie’ & Neurology Department, Grenoble, France
| | - Monica Baciu
- Université Grenoble Alpes, CNRS LPNC UMR 5105, Grenoble, France
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The Impact of Right Temporal Lobe Epilepsy On Nonverbal Memory: Meta-regression of Stimulus- and Task-related Moderators. Neuropsychol Rev 2021; 32:537-557. [PMID: 34559363 DOI: 10.1007/s11065-021-09514-3] [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: 06/01/2020] [Accepted: 05/24/2021] [Indexed: 11/08/2022]
Abstract
Nonverbal memory tests have great potential value for detecting the impact of lateralized pathology and predicting the risk of memory loss following right temporal lobe resection (TLR) for temporal lobe epilepsy (TLE) patients, but this potential has not been realized. Previous reviews suggest that stimulus type moderates the capacity of nonverbal memory tests to detect right-lateralized pathology (i.e., faces > designs), but the roles of other task-related factors have not been systematically explored. We address these limitations using mixed model meta-regression (k = 158) of right-lateralization effects (right worse than left TLE) testing the moderating effects of: 1) stimulus type (designs, faces, spatial), 2) learning format (single trial, repeated trials), 3) testing delay (immediate or long delay), and 4) testing format (recall, recognition) for three patient scenarios: 1) presurgical, 2) postsurgical, and 3) postsurgical change. Stimulus type significantly moderated the size of the right-lateralization effect (faces > designs) for postsurgical patients, test format moderated the size of the right-lateralization effect for presurgical-postsurgical change (recognition > recall) but learning format and test delay had no right-lateralization effect for either sample. For presurgical patients, none of the task-related factors significantly increased right-lateralization effects. This comprehensive review reveals the value of recognition testing in gauging the risk of nonverbal memory decline.
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Doll A, Wegrzyn M, Benzait A, Mertens M, Woermann FG, Labudda K, Bien CG, Kissler J. Whole-brain functional correlates of memory formation in mesial temporal lobe epilepsy. NEUROIMAGE-CLINICAL 2021; 31:102723. [PMID: 34147817 PMCID: PMC8220377 DOI: 10.1016/j.nicl.2021.102723] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 06/06/2021] [Accepted: 06/07/2021] [Indexed: 11/29/2022]
Abstract
Large study of encoding and subsequent memory for words, faces, and scenes. Less ipsilateral mesial temporal activity in mesial temporal lobe epilepsy (mTLE). Extra-mTL activity in mTLE only partly relevant for memory formation. Across materials contralateral mTL decisive to maintain intact memory in mTLE. Left frontal activation correlates with better verbal memory only in left mTLE.
The mesial temporal lobe is a key region for episodic memory. Accordingly, memory impairment is frequent in patients with mesial temporal lobe epilepsy. However, the functional relevance of potentially epilepsy-induced reorganisation for memory formation is still not entirely clear. Therefore, we investigated whole-brain functional correlates of verbal and non-verbal memory encoding and subsequent memory formation in 56 (25 right sided) mesial temporal lobe epilepsy patients and 21 controls. We applied an fMRI task of learning scenes, faces, and words followed by an out-of-scanner recognition test. During encoding of faces and scenes left and right mesial temporal lobe epilepsy patients had consistently reduced activation in the epileptogenic mesial temporal lobe compared with controls. Activation increases in patients were apparent in extra-temporal regions, partly associated with subsequent memory formation (left frontal regions and basal ganglia), and patients had less deactivation in regions often linked to the default mode and auditory networks. The more specific subsequent memory contrast indicated only marginal group differences. Correlating patients’ encoding activation with memory performance both within the paradigm and with independent clinical measures demonstrated predominantly increased contralateral mesio-temporal activation supporting intact memory performance. In left temporal lobe epilepsy patients, left frontal activation was also correlated with better verbal memory performance. Taken together, our findings hint towards minor extra-temporal plasticity in mesial temporal lobe epilepsy patients, which is in line with pre-surgical impairment and post-surgical memory decline in many patients. Further, data underscore the importance of particularly the contralateral mesial temporal lobe itself, to maintain intact memory performance.
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Affiliation(s)
- Anna Doll
- Bielefeld University, Medical School, Department of Epileptology (Krankenhaus Mara), Maraweg 21, Bielefeld 33617, Germany; Bielefeld University, Department of Psychology, Universitätsstraße 25, Bielefeld 33615, Germany.
| | - Martin Wegrzyn
- Bielefeld University, Department of Psychology, Universitätsstraße 25, Bielefeld 33615, Germany
| | - Anissa Benzait
- Bielefeld University, Medical School, Department of Epileptology (Krankenhaus Mara), Maraweg 21, Bielefeld 33617, Germany; Bielefeld University, Department of Psychology, Universitätsstraße 25, Bielefeld 33615, Germany
| | - Markus Mertens
- Bielefeld University, Medical School, Department of Epileptology (Krankenhaus Mara), Maraweg 21, Bielefeld 33617, Germany
| | - Friedrich G Woermann
- Bielefeld University, Medical School, Department of Epileptology (Krankenhaus Mara), Maraweg 21, Bielefeld 33617, Germany
| | - Kirsten Labudda
- Bielefeld University, Department of Psychology, Universitätsstraße 25, Bielefeld 33615, Germany
| | - Christian G Bien
- Bielefeld University, Medical School, Department of Epileptology (Krankenhaus Mara), Maraweg 21, Bielefeld 33617, Germany
| | - Johanna Kissler
- Bielefeld University, Department of Psychology, Universitätsstraße 25, Bielefeld 33615, Germany; Center for Cognitive Interaction Technology (CITEC), University of Bielefeld, Inspiration 1, Bielefeld 33619, Germany
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Abstract
Human neuroimaging has had a major impact on the biological understanding of epilepsy and the relationship between pathophysiology, seizure management, and outcomes. This review highlights notable recent advancements in hardware, sequences, methods, analyses, and applications of human neuroimaging techniques utilized to assess epilepsy. These structural, functional, and metabolic assessments include magnetic resonance imaging (MRI), positron emission tomography (PET), and magnetoencephalography (MEG). Advancements that highlight non-invasive neuroimaging techniques used to study the whole brain are emphasized due to the advantages these provide in clinical and research applications. Thus, topics range across presurgical evaluations, understanding of epilepsy as a network disorder, and the interactions between epilepsy and comorbidities. New techniques and approaches are discussed which are expected to emerge into the mainstream within the next decade and impact our understanding of epilepsies. Further, an increasing breadth of investigations includes the interplay between epilepsy, mental health comorbidities, and aberrant brain networks. In the final section of this review, we focus on neuroimaging studies that assess bidirectional relationships between mental health comorbidities and epilepsy as a model for better understanding of the commonalities between both conditions.
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Affiliation(s)
- Adam M. Goodman
- Department of Neurology, UAB Epilepsy Center, University of Alabama At Birmingham, 312 Civitan International Research Center, Birmingham, AL 35294 USA
| | - Jerzy P. Szaflarski
- Department of Neurology, UAB Epilepsy Center, University of Alabama At Birmingham, 312 Civitan International Research Center, Birmingham, AL 35294 USA
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9
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Li Q, Tavakol S, Royer J, Larivière S, Vos De Wael R, Park BY, Paquola C, Zeng D, Caldairou B, Bassett DS, Bernasconi A, Bernasconi N, Frauscher B, Smallwood J, Caciagli L, Li S, Bernhardt BC. Atypical neural topographies underpin dysfunctional pattern separation in temporal lobe epilepsy. Brain 2021; 144:2486-2498. [PMID: 33730163 DOI: 10.1093/brain/awab121] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 01/26/2021] [Accepted: 02/11/2021] [Indexed: 12/14/2022] Open
Abstract
Episodic memory is the ability to accurately remember events from our past. The process of pattern separation is hypothesized to underpin this ability and is defined as the ability to orthogonalize memory traces, to maximize the features that make them unique. Contemporary cognitive neuroscience suggests that pattern separation entails complex interactions between the hippocampus and the neocortex, where specific hippocampal subregions shape neural reinstatement in the neocortex. To test this hypothesis, the current work studied both healthy controls and patients with temporal lobe epilepsy (TLE) who present with hippocampal structural anomalies. In all participants, we measured neural activity using functional magnetic resonance imaging (fMRI) while they retrieved memorized items compared to lure items which share features with the target. Behaviorally, TLE patients were less able to exclude lures than controls, and showed a reduction in pattern separation. To assess the hypothesized relationship between neural patterns in the hippocampus and the neocortex, we identified topographic gradients of intrinsic connectivity along neocortical and hippocampal subfield surfaces and identified the topographic profile of the neural activity accompanying pattern separation. In healthy controls, pattern separation followed a graded pattern of neural activity, both along the hippocampal long axis (and peaked in anterior segments that are more heavily engaged in transmodal processing) and along the neocortical hierarchy running from unimodal to transmodal regions (peaking in transmodal default mode regions). In TLE patients, however, this concordance between task-based functional activations and topographic gradients was markedly reduced. Furthermore, person specific measures of concordance between task-related activity and connectivity gradients in patients and controls related to inter-individual differences in behavioral measures of pattern separation and episodic memory, highlighting the functional relevance of the observed topographic motifs. Our work is consistent with an emerging understanding that successful discrimination between memories with similar features entails a shift in the locus of neural activity away from sensory systems, a pattern that is mirrored along the hippocampal long axis and with respect to neocortical hierarchies. More broadly, our study establishes topographic profiling using intrinsic connectivity gradients captures the functional underpinnings of episodic memory processes in manner that is sensitive to their reorganization in pathology.
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Affiliation(s)
- Qiongling Li
- Multimodal Imaging and Connectome Analysis Laboratory, McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada.,School of Biological Science and Medical Engineering, Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, 100083, China
| | - Shahin Tavakol
- Multimodal Imaging and Connectome Analysis Laboratory, McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Jessica Royer
- Multimodal Imaging and Connectome Analysis Laboratory, McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Sara Larivière
- Multimodal Imaging and Connectome Analysis Laboratory, McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Reinder Vos De Wael
- Multimodal Imaging and Connectome Analysis Laboratory, McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Bo-Yong Park
- Multimodal Imaging and Connectome Analysis Laboratory, McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Casey Paquola
- Multimodal Imaging and Connectome Analysis Laboratory, McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Debin Zeng
- School of Biological Science and Medical Engineering, Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, 100083, China
| | - Benoit Caldairou
- Neuroimaging of Epilepsy Laboratory, McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Danielle S Bassett
- Department of Bioengineering, University of Pennsylvania, Philadelphia, USA.,Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, USA.,Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, USA.,Department of Neurology, University of Pennsylvania, Philadelphia, USA.,Department of Psychiatry, University of Pennsylvania, Philadelphia, USA.,Santa Fe Institute, Santa Fe, New Mexico, USA
| | - Andrea Bernasconi
- Neuroimaging of Epilepsy Laboratory, McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Neda Bernasconi
- Neuroimaging of Epilepsy Laboratory, McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
| | - Birgit Frauscher
- Montreal Neurological Institute, McGill University, Montreal, Canada
| | | | - Lorenzo Caciagli
- Department of Bioengineering, University of Pennsylvania, Philadelphia, USA
| | - Shuyu Li
- School of Biological Science and Medical Engineering, Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing, 100083, China
| | - Boris C Bernhardt
- Multimodal Imaging and Connectome Analysis Laboratory, McConnell Brain Imaging Centre, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada
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Dilcher R, Malpas CB, Walterfang M, Kwan P, O'Brien TJ, Velakoulis D, Vivash L. Cognitive profiles in patients with epileptic and nonepileptic seizures evaluated using a brief cognitive assessment tool. Epilepsy Behav 2021; 115:107643. [PMID: 33317941 DOI: 10.1016/j.yebeh.2020.107643] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 11/16/2020] [Accepted: 11/16/2020] [Indexed: 11/15/2022]
Abstract
BACKGROUND There is a need for the development of brief tools to screen for cognitive impairments in epilepsy patients in order to prioritize and direct formal comprehensive cognitive testing. Yet, shorter cognitive screening tools are limited in their breadth of cognitive domains or have not been intensively studied on an epilepsy population. This study used a brief cognitive screening tool in order to compare cognitive profiles between patients with epilepsy and those with nonepileptic seizures. METHODS Patients admitted to the Royal Melbourne Hospital video-EEG monitoring unit between 2005 and 2017 were included. Patients were categorized according to seizure etiology (epileptic, psychogenic or other nonepileptic seizures), epilepsy syndrome (focal or generalized; temporal lobe (TLE) or extra-temporal lobe epilepsy (ETLE)), seizure frequency, and anti-seizure medications (ASMs). Attention, visuoconstructional, memory, executive, and language functioning were assessed with the Neuropsychiatry Unit Cognitive Assessment Tool (NUCOG). General linear mixed models were computed to investigate cognitive profiles according to diagnostic group and other clinicodemographic variables. RESULTS 800 patients were included in the analysis (61% female and 39 % male, median age 36 years). Patients with both epileptic seizures and psychogenic seizures (n = 25) had the lowest total scores on NUCOG, followed by patients with epileptic seizures (n = 411), psychogenic seizures (n = 185), and nonepileptic seizures (n = 179, p = 0.002). Specifically, patients with epileptic seizures performed worse than those with nonepileptic seizures in the executive, language, and memory domain, and had lower language domain scores than those with psychogenic seizures. Patients with bilateral TLE had poorer performance than those with unilateral TLE, particularly for memory function. Specific ASMs and polypharmacy but not seizure frequency had a negative effect on cognition (p < 0.001). NUCOG scores did not differ between focal and generalized epilepsies, or between TLE and ETLE. CONCLUSION The NUCOG differentiated cognitive profiles in patients with uncontrolled seizures due to different etiologies. Bilateral TLE and medication adversely affected cognitive performance, and overall patients with epilepsy performed worse than those with nonepileptic seizures. These results provide further evidence for sensitivity of the NUCOG for detecting cognitive impairment in patients with seizure disorders.
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Affiliation(s)
- Roxane Dilcher
- Melbourne Brain Centre, The Department of Medicine, The Royal Melbourne Hospital, The University of Melbourne, Melbourne, VIC, Australia; Department of Neuroscience, Central Clinical School, Alfred Health, Monash University, Melbourne, VIC, Australia
| | - Charles B Malpas
- Department of Neurology, Royal Melbourne Hospital, Melbourne, VIC, Australia; Department of Neuroscience, Central Clinical School, Alfred Health, Monash University, Melbourne, VIC, Australia; Clinical Outcomes Research Unit (CORe), Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, VIC, Australia
| | - Mark Walterfang
- Neuropsychiatry Unit, Royal Melbourne Hospital, Melbourne, VIC, Australia; Melbourne Neuropsychiatry Centre, University of Melbourne and North Western Mental Health, Melbourne, VIC, Australia
| | - Patrick Kwan
- Melbourne Brain Centre, The Department of Medicine, The Royal Melbourne Hospital, The University of Melbourne, Melbourne, VIC, Australia; Department of Neurology, Royal Melbourne Hospital, Melbourne, VIC, Australia; Department of Neuroscience, Central Clinical School, Alfred Health, Monash University, Melbourne, VIC, Australia
| | - Terence J O'Brien
- Melbourne Brain Centre, The Department of Medicine, The Royal Melbourne Hospital, The University of Melbourne, Melbourne, VIC, Australia; Department of Neurology, Royal Melbourne Hospital, Melbourne, VIC, Australia; Department of Neuroscience, Central Clinical School, Alfred Health, Monash University, Melbourne, VIC, Australia
| | - Dennis Velakoulis
- Department of Neurology, Royal Melbourne Hospital, Melbourne, VIC, Australia; Neuropsychiatry Unit, Royal Melbourne Hospital, Melbourne, VIC, Australia
| | - Lucy Vivash
- Melbourne Brain Centre, The Department of Medicine, The Royal Melbourne Hospital, The University of Melbourne, Melbourne, VIC, Australia; Department of Neurology, Royal Melbourne Hospital, Melbourne, VIC, Australia; Department of Neuroscience, Central Clinical School, Alfred Health, Monash University, Melbourne, VIC, Australia.
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11
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Larivière S, Bernasconi A, Bernasconi N, Bernhardt BC. Connectome biomarkers of drug-resistant epilepsy. Epilepsia 2020; 62:6-24. [PMID: 33236784 DOI: 10.1111/epi.16753] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 09/29/2020] [Accepted: 10/16/2020] [Indexed: 02/06/2023]
Abstract
Drug-resistant epilepsy (DRE) considerably affects patient health, cognition, and well-being, and disproportionally contributes to the overall burden of epilepsy. The most common DRE syndromes are temporal lobe epilepsy related to mesiotemporal sclerosis and extratemporal epilepsy related to cortical malformations. Both syndromes have been traditionally considered as "focal," and most patients benefit from brain surgery for long-term seizure control. However, increasing evidence indicates that many DRE patients also present with widespread structural and functional network disruptions. These anomalies have been suggested to relate to cognitive impairment and prognosis, highlighting their importance for patient management. The advent of multimodal neuroimaging and formal methods to quantify complex systems has offered unprecedented ability to profile structural and functional brain networks in DRE patients. Here, we performed a systematic review on existing DRE network biomarker candidates and their contribution to three key application areas: (1) modeling of cognitive impairments, (2) localization of the surgical target, and (3) prediction of clinical and cognitive outcomes after surgery. Although network biomarkers hold promise for a range of clinical applications, translation of neuroimaging biomarkers to the patient's bedside has been challenged by a lack of clinical and prospective studies. We therefore close by highlighting conceptual and methodological strategies to improve the evaluation and accessibility of network biomarkers, and ultimately guide clinically actionable decisions.
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Affiliation(s)
- Sara Larivière
- Multimodal Imaging and Connectome Analysis Laboratory, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Andrea Bernasconi
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Neda Bernasconi
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Boris C Bernhardt
- Multimodal Imaging and Connectome Analysis Laboratory, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
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12
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Trimmel K, Caciagli L, Xiao F, van Graan LA, Koepp MJ, Thompson PJ, Duncan JS. Impaired naming performance in temporal lobe epilepsy: language fMRI responses are modulated by disease characteristics. J Neurol 2020; 268:147-160. [PMID: 32747979 PMCID: PMC7815622 DOI: 10.1007/s00415-020-10116-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 07/23/2020] [Accepted: 07/24/2020] [Indexed: 10/27/2022]
Abstract
OBJECTIVE To investigate alterations of language networks and their relation to impaired naming performance in temporal lobe epilepsy (TLE) using functional MRI. METHODS Seventy-two adult TLE patients (41 left) and 36 controls were studied with overt auditory and picture naming fMRI tasks to assess temporal lobe language areas, and a covert verbal fluency task to probe frontal lobe language regions. Correlation of fMRI activation with clinical naming scores, and alteration of language network patterns in relation to epilepsy duration, age at onset and seizure frequency, were investigated with whole-brain multiple regression analyses. RESULTS Auditory and picture naming fMRI activated the left posterior temporal lobe, and stronger activation correlated with better clinical naming scores. Verbal fluency MRI mainly activated frontal lobe regions. In left and right TLE, a later age of epilepsy onset related to stronger temporal lobe activations, while earlier age of onset was associated with impaired deactivation of extratemporal regions. In left TLE patients, longer disease duration and higher seizure frequency were associated with reduced deactivation. Frontal lobe language networks were unaffected by disease characteristics. CONCLUSIONS While frontal lobe language regions appear spared, temporal lobe language areas are susceptible to dysfunction and reorganisation, particularly in left TLE. Early onset and long duration of epilepsy, and high seizure frequency, were associated with compromised activation and deactivation patterns of task-associated regions, which might account for impaired naming performance in individuals with TLE.
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Affiliation(s)
- Karin Trimmel
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, UK. .,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, UK. .,Department of Neurology, Medical University of Vienna, 1090, Vienna, Austria.
| | - Lorenzo Caciagli
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, UK.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Fenglai Xiao
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, UK.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Louis A van Graan
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, UK.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Matthias J Koepp
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, UK.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Pamela J Thompson
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, UK.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - John S Duncan
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, UK.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, UK
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13
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Chaudhary K, Tripathi M, Chandra PS, Nehra A, Kumaran SS. Evaluation of memory in persons with mesial temporal lobe sclerosis: A combined fMRI and VBM study. J Biosci 2020. [DOI: 10.1007/s12038-020-00041-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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14
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Pajkert A, Ploner CJ, Lehmann TN, Witte VA, Oltmanns F, Sommer W, Holtkamp M, Heekeren HR, Finke C. Early volumetric changes of hippocampus and medial prefrontal cortex following medial temporal lobe resection. Eur J Neurosci 2020; 52:4375-4384. [PMID: 32421911 DOI: 10.1111/ejn.14784] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 05/07/2020] [Accepted: 05/09/2020] [Indexed: 12/14/2022]
Abstract
Previous studies have shown that cognitive demands and physical exercise stimulate adult neurogenesis in the dentate gyrus and hippocampus. Recent observations in healthy humans and patients with mild cognitive impairment moreover suggest that training-induced increases in hippocampal volume may be associated with improved memory performance. The corresponding plasticity processes in hippocampal volume may occur on timescales of months to years. For patients with focal lesions in this region, previous functional imaging studies suggest that increased recruitment of the contralateral hippocampus and extratemporal regions may be an important part of the reorganization of episodic memory. However, it is currently unclear whether focal damage to the medial temporal lobe (MTL) induces gray matter (GM) volume changes in the intact contralateral hippocampus and in connected network regions on a shorter timescale. We therefore investigated whether unilateral resection of the MTL, including the hippocampus, induces measurable volumetric changes in the contralateral hippocampus and in the default mode network (DMN). We recruited 31 patients with unilateral left (N = 19) or right (N = 12) hippocampal sclerosis undergoing MTL resection for treatment of drug-resistant epilepsy. Structural MRI was acquired immediately before and 3 months after surgery. Longitudinal voxel-based morphometry (VBM) analysis revealed a significant increase of right hippocampal volume following resection of the left anterior MTL. Furthermore, this patient group showed GM volume increases in the DMN. These results demonstrate significant structural plasticity of the contralateral hippocampus, even in patients with a long-standing unilateral hippocampal dysfunction and structural reorganization processes extending to distant, but functionally connected brain regions.
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Affiliation(s)
- Anna Pajkert
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Christoph J Ploner
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | | | - Veronica A Witte
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | | | - Werner Sommer
- Institut für Psychologie, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Martin Holtkamp
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Epilepsy-Center Berlin-Brandenburg, Berlin, Germany
| | - Hauke R Heekeren
- Department of Education and Psychology, Freie Universität Berlin, Berlin, Germany.,Center for Cognitive Neuroscience Berlin, Freie Universität Berlin, Berlin, Germany
| | - Carsten Finke
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin School of Mind & Brain, Humboldt-Universität zu Berlin, Berlin, Germany
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15
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Buck S, Sidhu MK. A Guide to Designing a Memory fMRI Paradigm for Pre-surgical Evaluation in Temporal Lobe Epilepsy. Front Neurol 2020; 10:1354. [PMID: 31998216 PMCID: PMC6962296 DOI: 10.3389/fneur.2019.01354] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 12/09/2019] [Indexed: 12/05/2022] Open
Abstract
There has been increasing interest in the clinical and experimental use of memory functional Magnetic Resonance Imaging (fMRI). The 2017 American Academy of Neurology practice guidelines on the use of pre-surgical cognitive fMRI suggests that verbal memory fMRI could be used to lateralize memory functions in people with Temporal Lobe Epilepsy (TLE) and should be used to predict post-operative verbal memory outcome. There are however technical and methodological considerations, to optimize both the sensitivity and specificity of this imaging modality. Below we discuss these constraints and suggest recommendations to consider when designing a memory fMRI paradigm.
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Affiliation(s)
- Sarah Buck
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology of Neurology, London, United Kingdom
- Epilepsy Society MRI Unit, Chalfont Saint Peter, United Kingdom
| | - Meneka K. Sidhu
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology of Neurology, London, United Kingdom
- Epilepsy Society MRI Unit, Chalfont Saint Peter, United Kingdom
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16
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Gelfuso EA, Reis SL, Pereira AMS, Aguiar DSR, Beleboni RO. Neuroprotective effects and improvement of learning and memory elicited by erythravine and 11α-hydroxy-erythravine against the pilocarpine model of epilepsy. Life Sci 2020; 240:117072. [PMID: 31751584 DOI: 10.1016/j.lfs.2019.117072] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 11/13/2019] [Accepted: 11/14/2019] [Indexed: 12/19/2022]
Abstract
Deficits in cognitive functions are often observed in epileptic patients, particularly in temporal lobe epilepsy (TLE). Evidence suggests that this cognitive decline can be associated with the occurrence of focal brain lesions, especially on hippocampus and cortex regions. We previously demonstrated that the erythrinian alkaloids, (+)-erythravine and (+)-11α-hydroxy-erythravine, inhibit seizures evoked in rats by different chemoconvulsants. AIMS The current study evaluated if these alkaloids would be acting in a neuroprotective way, reducing hippocampal sclerosis, and consequently, improving learning/memory performance. MAIN METHODS Here we confirmed the anticonvulsant effect of both alkaloids by means of the pilocarpine seizure-induced model and also showed that they enhanced spatial learning of rats submitted to the Morris Water Maze test reverting the cognition deficit. Additionally, immunohistochemistry assays showed that neuronal death and glial activation were prevented by the alkaloids in the hippocampus CA1, CA3 and dentate gyrus regions at both hemispheres indistinctly 15 days after status epilepticus induction. KEY FINDINGS Our results show, for the first-time, the improvement on memory/learning elicited by these erythrinian alkaloids. Furthermore, data presented herein explain, at least partially, the cellular mechanism of action of these alkaloids. Together, (+)-erythravine and (+)-11α-hydroxy-erythravine seem to be a promising protective strategy against TLE, comprising three main aspects: neuroprotection, control of epileptic seizures and cognitive improvement. SIGNIFICANCE Moreover, our findings on neuroprotection corroborate the view that seizure frequency and severity, hippocampal lesions and memory deficits are interconnected events.
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Affiliation(s)
- Erica Aparecida Gelfuso
- Department of Biotechnology, University of Ribeirão Preto, Ribeirão Preto, São Paulo, Brazil
| | - Suelen Lorenzato Reis
- Department of Biotechnology, University of Ribeirão Preto, Ribeirão Preto, São Paulo, Brazil
| | | | | | - Renê Oliveira Beleboni
- Department of Biotechnology, University of Ribeirão Preto, Ribeirão Preto, São Paulo, Brazil; School of Medicine, University of Ribeirão Preto, Ribeirão Preto, São Paulo, Brazil.
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17
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Hill PF, King DR, Lega BC, Rugg MD. Comparison of fMRI correlates of successful episodic memory encoding in temporal lobe epilepsy patients and healthy controls. Neuroimage 2019; 207:116397. [PMID: 31770638 PMCID: PMC7238288 DOI: 10.1016/j.neuroimage.2019.116397] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Revised: 10/23/2019] [Accepted: 11/22/2019] [Indexed: 12/30/2022] Open
Abstract
Intra-cranial electroencephalographic brain recordings (iEEG) provide a powerful tool for investigating the neural processes supporting episodic memory encoding and form the basis of experimental therapies aimed at improving memory dysfunction. However, given the invasiveness of iEEG, investigations are constrained to patients with drug-resistant epilepsy for whom such recordings are clinically indicated. Particularly in the case of temporal lobe epilepsy (TLE), neuropathology and the possibility of functional reorganization are potential constraints on the generalizability of intra-cerebral findings and pose challenges to the development of therapies for memory disorders stemming from other etiologies. Here, samples of TLE (N = 16; all of whom had undergone iEEG) and age-matched healthy control (N = 19) participants underwent fMRI as they studied lists of concrete nouns. fMRI BOLDresponses elicited by the study words were segregated according to subsequent performance on tests of delayed free recall and recognition memory. Subsequent memory effects predictive of both successful recall and recognition memory were evident in several neural regions, most prominently in the left inferior frontal gyrus, and did not demonstrate any group differences. Behaviorally, the groups did not differ in overall recall performance or in the strength of temporal contiguity effects. However, group differences in serial position effects and false alarm rates were evident during the free recall and recognition memory tasks, respectively. Despite these behavioral differences, neuropathology associated with temporal lobe epilepsy was apparently insufficient to give rise to detectable differences in the functional neuroanatomy of episodic memory encoding relative to neurologically healthy controls. The findings provide reassurance that iEEG findings derived from experimental paradigms similar to those employed here generalize to the neurotypical population.
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Affiliation(s)
- Paul F Hill
- Center for Vital Longevity, University of Texas at Dallas, 1600 Viceroy Dr. #800, Dallas, TX, 75235, USA; School of Behavioral and Brain Sciences, University of Texas at Dallas, 800 W Campbell Rd, Richardson, TX, 75080, USA.
| | - Danielle R King
- Center for Vital Longevity, University of Texas at Dallas, 1600 Viceroy Dr. #800, Dallas, TX, 75235, USA; School of Behavioral and Brain Sciences, University of Texas at Dallas, 800 W Campbell Rd, Richardson, TX, 75080, USA
| | - Bradley C Lega
- Department of Neurosurgery, University of Texas Southwestern Medical Center, 5303 Harry Hines Blvd 6th Floor Suite 108, Dallas, TX, 75390, USA
| | - Michael D Rugg
- Center for Vital Longevity, University of Texas at Dallas, 1600 Viceroy Dr. #800, Dallas, TX, 75235, USA; School of Behavioral and Brain Sciences, University of Texas at Dallas, 800 W Campbell Rd, Richardson, TX, 75080, USA; Department of Psychiatry, University of Texas Southwestern Medical Center, 6363 Forest Park Rd 7th Floor Suite 749, Dallas, TX, 75235, USA
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18
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Jeong W, Lee H, Kim JS, Chung CK. Neural basis of episodic memory in the intermediate term after medial temporal lobe resection. J Neurosurg 2019; 131:790-798. [PMID: 30485238 DOI: 10.3171/2018.5.jns18199] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 05/02/2018] [Indexed: 12/31/2022]
Abstract
OBJECTIVE How the brain supports intermediate-term preservation of memory in patients who have undergone unilateral medial temporal lobe resection (MTLR) has not yet been demonstrated. To understand the neural basis of episodic memory in the intermediate term after surgery for temporal lobe epilepsy (TLE), the authors investigated the relationship between the activation of the hippocampus (HIP) during successful memory encoding and individual memory capacity in patients who had undergone MTLR. They also compared hippocampal activation with other parameters, including structural volumes of the HIP, duration of illness, and age at seizure onset. METHODS Thirty-five adult patients who had undergone unilateral MTLR at least 1 year before recruiting and who had a favorable seizure outcome were enrolled (17 left MTLR, 18 right MTLR; mean follow-up 6.31 ± 2.72 years). All patients underwent a standardized neuropsychological examination of memory function and functional MRI scanning with a memory-encoding paradigm of words and figures. Activations of the HIP during successful memory encoding were calculated and compared with standard neuropsychological memory scores, hippocampal volumes, and other clinical variables. RESULTS Greater activation in the HIP contralateral to the side of the resection was related to higher postoperative memory scores and greater postoperative memory improvement than the preoperative baseline in both patient groups. Specifically, postoperative verbal memory performance was positively correlated with contralateral right hippocampal activation during word encoding in the left-sided surgery group. In contrast, postoperative visual memory performance was positively correlated with contralateral left hippocampal activation during figure encoding in the right-sided surgery group. Activation of the ipsilateral remnant HIP was not correlated with any memory scores or volumes of the HIP; however, it had a negative correlation with the seizure-onset age and positive correlation with the duration of illness in both patient groups. CONCLUSIONS For the first time, a neural basis that supports effective intermediate-term episodic memory after unilateral MTLR has been characterized. The results provide evidence that engagement of the HIP contralateral rather than ipsilateral to the side of resection is responsible for effective memory function in the intermediate term (> 1 year) after surgery in patients who have undergone left MTLR and right MTLR. Engagement of the material-specific contralesional HIP, verbal memory in the left-sided surgery group, and visual memory in the right-sided surgery group were observed.
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Affiliation(s)
- Woorim Jeong
- 1Neuroscience Research Institute, Seoul National University College of Medicine.,2Department of Neurosurgery, Seoul National University Hospital
| | - Hyeongrae Lee
- 3Department of Mental Health Research, National Center for Mental Health; and
| | - June Sic Kim
- 4Department of Brain and Cognitive Sciences, Seoul National University College of Natural Sciences, Seoul, Korea
| | - Chun Kee Chung
- 1Neuroscience Research Institute, Seoul National University College of Medicine.,2Department of Neurosurgery, Seoul National University Hospital.,4Department of Brain and Cognitive Sciences, Seoul National University College of Natural Sciences, Seoul, Korea
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19
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Episodic simulation and empathy in older adults and patients with unilateral medial temporal lobe excisions. Neuropsychologia 2019; 135:107243. [PMID: 31698010 DOI: 10.1016/j.neuropsychologia.2019.107243] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 10/29/2019] [Accepted: 10/30/2019] [Indexed: 12/18/2022]
Abstract
Recent work shows that vividly imagining oneself helping others in situations of need (episodic simulation) increases one's willingness to help. The mechanisms underlying this effect are unclear, though it is known that the medial temporal lobe (MTL) is critical for supporting episodic simulation in general. Therefore, individuals who have compromised MTL functioning, such as older adults and those who have undergone resection of medial temporal lobe tissue as treatment for epilepsy (mTLE patients), may not show the prosocial effects of episodic simulation. Our lab previously found that older adults and mTLE patients are impaired on a problem-solving task that requires the simulation of hypothetical scenarios. Using similar logic in the present study, we predicted that older adults and mTLE patients would show reduced effects of episodic simulation on their empathic concern for, and willingness to help, people in hypothetical situations of need, compared to young adults and age-matched healthy controls, respectively. We also predicted that the subjective vividness and the amount of context-specific detail in imagined helping events would correlate with willingness to help and empathic concern. Participants read brief stories describing individuals in situations of need, and after each story either imagined themselves helping the person or performed a filler task. We analyzed the details in participants' oral descriptions of their imagined helping events and also collected subjective ratings of vividness, willingness to help, and empathic concern. Episodic simulation significantly boosted willingness to help in all groups except for mTLE patients, and it increased empathic concern in young adults and healthy controls but not in older adults or mTLE patients. While the level of context-specific detail in participants' oral descriptions of imaged events was unrelated to willingness to help and empathic concern, the effects of episodic simulation on these measures was completely mediated by subjective vividness, though to a significantly lesser degree among mTLE patients. These results increase our understanding not only of how episodic simulation works in healthy people, but also of the social and emotional consequences of compromised MTL functioning.
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20
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Trimmel K, van Graan LA, Gonzálvez GG, Haag A, Caciagli L, Vos SB, Bonelli S, Sidhu M, Thompson PJ, Koepp MJ, Duncan JS. Naming fMRI predicts the effect of temporal lobe resection on language decline. Ann Clin Transl Neurol 2019; 6:2186-2196. [PMID: 31578819 PMCID: PMC6856622 DOI: 10.1002/acn3.50911] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 09/11/2019] [Indexed: 11/08/2022] Open
Abstract
OBJECTIVE To develop language functional MRI (fMRI) methods that accurately predict postsurgical naming decline in temporal lobe epilepsy (TLE). METHODS Forty-six patients with TLE (25 left) and 19 controls underwent two overt fMRI paradigms (auditory naming and picture naming, both with active baseline conditions) and one covert task (verbal fluency). Clinical naming performance was assessed preoperatively and 4 months following anterior temporal lobe resection. Preoperative fMRI activations were correlated with postoperative naming decline. Individual laterality indices (LI) were calculated for temporal (auditory and picture naming) and frontal regions (verbal fluency) and were considered as predictors of naming decline in multiple regression models, along with other clinical variables (age at onset of seizures, preoperative naming scores, hippocampal volume, age). RESULTS In left TLE patients, activation of the left posterior inferior temporal gyrus during auditory naming and activation of left fusiform gyrus during picture naming were related to greater postoperative naming decline. Activation LI were the best individual predictors of naming decline in a multivariate regression model. For picture naming, an LI of higher than 0.34 gave 100% sensitivity and 92% specificity (positive predictive value (PPV) 91.6%). For auditory naming, a temporal lobe LI higher than 0.18 identified all patients with a clinically significant naming decline with 100% sensitivity and 58% specificity (PPV: 58.3%). No effect was seen for verbal fluency. INTERPRETATION Auditory and picture naming fMRI are clinically applicable to predict postoperative naming decline after left temporal lobe resection in individual patients, with picture naming being more specific.
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Affiliation(s)
- Karin Trimmel
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, United Kingdom.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom.,Department of Neurology, Medical University of Vienna, A-1090, Vienna, Austria
| | - Louis A van Graan
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, United Kingdom.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom
| | - Gloria G Gonzálvez
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, United Kingdom.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom
| | - Anja Haag
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, United Kingdom.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom
| | - Lorenzo Caciagli
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, United Kingdom.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom
| | - Sjoerd B Vos
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, United Kingdom.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom.,Centre for Medical Image Computing, University College London, London, United Kingdom
| | - Silvia Bonelli
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, United Kingdom.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom.,Department of Neurology, Medical University of Vienna, A-1090, Vienna, Austria
| | - Meneka Sidhu
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, United Kingdom.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom
| | - Pamela J Thompson
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, United Kingdom.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom
| | - Matthias J Koepp
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, United Kingdom.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom
| | - John S Duncan
- Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, SL9 0LR, United Kingdom.,Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom
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Trajectories of brain remodeling in temporal lobe epilepsy. J Neurol 2019; 266:3150-3159. [PMID: 31549200 DOI: 10.1007/s00415-019-09546-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Revised: 09/12/2019] [Accepted: 09/14/2019] [Indexed: 12/24/2022]
Abstract
Temporal lobe epilepsy has been usually associated with progressive brain atrophy due to neuronal cell loss. However, recent animal models demonstrated a dual effect of epileptic seizures with initial enhancement of hippocampal neurogenesis followed by abnormal astrocyte proliferation and neurogenesis depletion in the chronic stage. Our aim was to test for the hypothesized bidirectional pattern of epilepsy-associated brain remodeling in the context of the presence and absence of mesial temporal lobe sclerosis. We acquired MRIs from a large cohort of mesial temporal lobe epilepsy patients with or without hippocampus sclerosis on radiological examination. The statistical analysis tested explicitly for common and differential brain patterns between the two patients' cohorts and healthy controls within the computational anatomy framework of voxel-based morphometry. The main effect of disease was associated with continuous hippocampus volume loss ipsilateral to the seizure onset zone in both temporal lobe epilepsy cohorts. The post hoc simple effects tests demonstrated bilateral hippocampus volume increase in the early epilepsy stages in patients without hippocampus sclerosis. Early age of onset and longer disease duration correlated with volume decrease in the ipsilateral hippocampus. Our findings of seizure-induced hippocampal remodeling are associated with specific patterns of mesial temporal lobe atrophy that are modulated by individual clinical phenotype features. Directionality of hippocampus volume changes strongly depends on the chronicity of disease. Specific anatomy differences represent a snapshot within a progressive continuum of seizure-induced structural remodeling.
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Abstract
Epilepsy is a chronic neurological condition, following some trigger, transforming a normal brain to one that produces recurrent unprovoked seizures. In the search for the mechanisms that best explain the epileptogenic process, there is a growing body of evidence suggesting that the epilepsies are network level disorders. In this review, we briefly describe the concept of neuronal networks and highlight 2 methods used to analyse such networks. The first method, graph theory, is used to describe general characteristics of a network to facilitate comparison between normal and abnormal networks. The second, dynamic causal modelling, is useful in the analysis of the pathways of seizure spread. We concluded that the end results of the epileptogenic process are best understood as abnormalities of neuronal circuitry and not simply as molecular or cellular abnormalities. The network approach promises to generate new understanding and more targeted treatment of epilepsy.
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Affiliation(s)
- Aminu T Abdullahi
- Department of Psychiatry, Aminu Kano Teaching Hospital, Kano, Nigeria
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Rice GE, Caswell H, Moore P, Lambon Ralph MA, Hoffman P. Revealing the Dynamic Modulations That Underpin a Resilient Neural Network for Semantic Cognition: An fMRI Investigation in Patients With Anterior Temporal Lobe Resection. Cereb Cortex 2018; 28:3004-3016. [PMID: 29878076 PMCID: PMC6041810 DOI: 10.1093/cercor/bhy116] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Indexed: 11/13/2022] Open
Abstract
One critical feature of any well-engineered system is its resilience to perturbation and minor damage. The purpose of the current study was to investigate how resilience is achieved in higher cognitive systems, which we explored through the domain of semantic cognition. Convergent evidence implicates the bilateral anterior temporal lobes (ATLs) as a conceptual knowledge hub. While bilateral damage to this region produces profound semantic impairment, unilateral atrophy/resection or transient perturbation has a limited effect. Two neural mechanisms might underpin this resilience to unilateral ATL damage: 1) the undamaged ATL upregulates its activation in order to compensate; and/or 2) prefrontal regions involved in control of semantic retrieval upregulate to compensate for the impoverished semantic representations that follow from ATL damage. To test these possibilities, 34 postsurgical temporal lobe epilepsy patients and 20 age-matched controls were scanned whilst completing semantic tasks. Pictorial tasks, which produced bilateral frontal and temporal activation, showed few activation differences between patients and control participants. Written word tasks, however, produced a left-lateralized activation pattern and greater differences between the groups. Patients with right ATL resection increased activation in left inferior frontal gyrus (IFG). Patients with left ATL resection upregulated both the right ATL and right IFG. Consistent with recent computational models, these results indicate that 1) written word semantic processing in patients with ATL resection is supported by upregulation of semantic knowledge and control regions, principally in the undamaged hemisphere, and 2) pictorial semantic processing is less affected, presumably because it draws on a more bilateral network.
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Affiliation(s)
- Grace E Rice
- Neuroscience and Aphasia Research Unit (NARU), University of Manchester, Manchester, UK
| | - Helen Caswell
- Department of Clinical Neuropsychology, Salford Royal Hospital, Manchester, UK
| | - Perry Moore
- Department of Clinical Neuropsychology, The Walton Centre NHS Foundation Trust, Liverpool, UK
| | | | - Paul Hoffman
- Centre for Cognitive Ageing and Cognitive Epidemiology (CCACE), Department of Psychology, University of Edinburgh, Edinburgh, UK
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Vaccaro MG, Trimboli M, Scarpazza C, Palermo L, Bruni A, Gambardella A, Labate A. Neuropsychological profile of mild temporal lobe epilepsy. Epilepsy Behav 2018; 85:222-226. [PMID: 30032811 DOI: 10.1016/j.yebeh.2018.06.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 05/25/2018] [Accepted: 06/07/2018] [Indexed: 11/25/2022]
Abstract
OBJECTIVE In the current literature, whether patients with mild mesial temporal lobe epilepsy (mMTLE) have typical neurocognitive profile similar to patients with treatment-refractory seizures still remains unknown. The purpose of the present work was to analyze the neuropsychological profile in a group of consecutive patients with mMTLE. METHODS Forty consecutive patients whose conditions were diagnosed with mMTLE and 30 healthy controls (HC) were evaluated with an extensive neuropsychological battery. In addition, self-report questionnaires were also administered to evaluate the subjective impairments in prospective and retrospective memories. Finally, the levels of depression and anxiety were evaluated using the Beck Depression Inventory II (BDI-II) and the State-Trait Anxiety Inventory - Form Y1 (STAI-YI e 2). RESULTS Patients with mMTLE patients showed higher BDI-II scores (15.9 ± 13.9 vs 7.2 ± 6.7; p =, 002), and higher STAI-Y1 (41.2 ± 14.6 vs 32.6 ± 9.8; p =, 005) together with both objective and subjective memory deficits. Although BDI-II and STAI scores strongly correlated to the outcome in Rey Auditory Verbal Learning Test (RAVLT) and prospective and retrospective memory questionnaire (PRMQ) (p < 0.0021), these results did not change without depression scores. CONCLUSION We showed that a specific neurocognitive profile in patients with mMTLE exists. The neuropsychological features are mood depression, verbal memory immediate and delayed deficits, and subjective prospective and retrospective memory deficits.
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Affiliation(s)
- Maria Grazia Vaccaro
- Department of Medical Sciences, Institute of Neurology, University Magna Græcia, Catanzaro, Italy
| | - Michele Trimboli
- Department of Medical Sciences, Institute of Neurology, University Magna Græcia, Catanzaro, Italy
| | - Cristina Scarpazza
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK; Department of General Psychology, University of Padua, Italy
| | - Liana Palermo
- Department of Medical and Surgical Sciences, Magna Graecia University of Catanzaro, Italy
| | - Antonella Bruni
- Department of Medical Sciences, Institute of Neurology, University Magna Græcia, Catanzaro, Italy
| | - Antonio Gambardella
- Department of Medical Sciences, Institute of Neurology, University Magna Græcia, Catanzaro, Italy
| | - Angelo Labate
- Department of Medical Sciences, Institute of Neurology, University Magna Græcia, Catanzaro, Italy.
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Zhou T, Wang N, Xu L, Huang H, Yu C, Zhou H. Effects of carbamazepine combined with vitamin B12 on levels of plasma homocysteine, hs-CRP and TNF-α in patients with epilepsy. Exp Ther Med 2018; 15:2327-2332. [PMID: 29563977 PMCID: PMC5854944 DOI: 10.3892/etm.2018.5698] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 12/11/2017] [Indexed: 01/24/2023] Open
Abstract
The efficacy of carbamazepine combined with vitamin B12 in epilepsy treatment by comparing levels of plasma homocysteine (Hcy), serum TNF-α and hs-CRP in patients with epilepsy before and after treatment was investigated. Fifty-eight patients with epilepsy who were admitted and received treatment in The First People's Hospital of Xuzhou were recruited as subjects, and fifty-eight healthy volunteers were recruited as the control group. Patients were treated with carbamazepine combined with vitamin B12 for a period of three months. The mRNA and protein levels of TNF-α and hs-CRP in serum were measured before and after treatment using semi-quantitative RT-PCR and western blotting, respectively. The plasma Hcy levels were measured as well. Within one year after the 3-month treatment, the frequency and duration of seizure were tracked. After treatment with carbamazepine combined with vitamin B12 for patients with epilepsy, the Hcy level was significantly higher than that before treatment and that in the control group (P<0.01). The mRNA and protein levels of TNF-α and hs-CRP in serum were significantly higher in patients than that in healthy people (P<0.01). After treatment these levels were reduced (P<0.01), but still higher than those in healthy people (P<0.05, P<0.01). After treatment, the frequency and duration of seizures were all reduced (P<0.05, P<0.01). The results suggested that carbamazepine combined with vitamin B12 was effective in treatment of epilepsy by reducing levels of TNF-α and hs-CRP in the serum, but had a risk of increasing the Hcy level.
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Affiliation(s)
- Tianchi Zhou
- School of Clinical Medicine, Kangda College of Nanjing Medical University, Lianyungang, Jiangsu 222002, P.R. China
| | - Nuan Wang
- Department of Neurology, The First People's Hospital of Xuzhou, Xuzhou, Jiangsu 221000, P.R. China
| | - Lei Xu
- Department of Pharmacy, The First People's Hospital of Xuzhou, Xuzhou, Jiangsu 221000, P.R. China
| | - Hongli Huang
- Department of Neurology, The First People's Hospital of Xuzhou, Xuzhou, Jiangsu 221000, P.R. China
| | - Chunyu Yu
- Department of Neurology, The First People's Hospital of Xuzhou, Xuzhou, Jiangsu 221000, P.R. China
| | - Hao Zhou
- Department of Neurology, The First People's Hospital of Xuzhou, Xuzhou, Jiangsu 221000, P.R. China
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Chaudhary K, Ramanujam B, Kumaran SS, Chandra PS, Wadhawan AN, Garg A, Tripathi M. Does education play a role in language reorganization after surgery in drug refractory temporal lobe epilepsy: An fMRI based study? Epilepsy Res 2017; 136:88-96. [PMID: 28802988 DOI: 10.1016/j.eplepsyres.2017.07.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 07/24/2017] [Accepted: 07/25/2017] [Indexed: 01/12/2023]
Abstract
OBJECTIVES Patients with drug refractory epilepsy (DRE) and a high level of education may differ in their language recovery after surgery. Our aim was to determine whether there were differences in the extent of improvement and pattern of reorganization of language functions on functional magnetic resonance imaging (fMRI) after surgery to treat refractory temporal lobe epilepsy (TLE) between patients with more than 12 years of formal education versus those with a shorter period of regular schooling. METHODS After approval by an institutional ethics committee, 60 right-handed, adult patients of left TLE and 20 right-handed, healthy controls were recruited to the study. Multiple aspects of language (Repetition, Naming, Word fluency, Visual word and Comprehension reading) were tested using the Indian Aphasia Battery (IAB) in the Hindi language; fMRI was performed using a standardized Hindi language paradigm (lexical, semantic, syntactic and comprehension components) in both cases and controls, before and after an anterior temporal lobectomy (in cases) with a 1.5T MR Scanner. An array of performance tests of intelligence and the verbal adult intelligence scale (VAIS) were used to measure the Intelligence Quotient (IQ) in Left TLE (LTLE) patients before and after surgery. Language laterality was estimated using the laterality index (LI-toolbox-spm8). Cohen's d test was performed to determine the effect sizes of the differences in the IAB scores, and Pearson's correlation was applied between regional (IFG and STG) activation in controls and TLE patients with more than 12 years of schooling [higher educational status (HES subgroup)] and those with less than 12 years of schooling [lower educational status (LES subgroup)]. RESULTS At the baseline, clinical testing with IAB showed better scores in controls than in cases. Better scores were observed in subjects with higher levels of education than in those with lower levels of education. An improvement was observed in IQ scores in both the HES and LES groups after ATLR; significant worsening in the abstract ability subtest was noted in the LES group, whereas in the HES group there was an improvement. Blood-oxygen-level dependent (BOLD) activation during language tasks was observed in both cerebral hemispheres in the TLE cases, while it was observed in the traditional left hemispheric language areas in controls. Postoperatively, greater BOLD activation was observed in the left inferior frontal gyri (IFG, r=0.65*; p<0.05), middle frontal gyrus (MFG, r=0.77**; p<0.01) superior temporal gyri (STG, r=0.88* p<0.02) and angular gyrus (AG, r=0.73*; p<0.04) in HES compared to LES subjects. Similarly, LI showed left lateralization of the frontal (LIw=0.77 & 0.71) and temporal (LIw=0.74 & 0.5) regions in controls and the TLE group (post-surgery) compared to the pre-surgery group during language tasks. CONCLUSIONS Greater improvement in language skills and BOLD activation in the left hemisphere in TLE-patients (after epilepsy surgery) with a high level of education was similar to that of healthy controls, implying that education has an effect on the functional reorganization/recovery of language areas.
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Affiliation(s)
- Kapil Chaudhary
- Department of Neurology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India
| | - Bhargavi Ramanujam
- Department of Neurology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India
| | - S Senthil Kumaran
- Department of NMR and MRI Facility, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India
| | - P Sarat Chandra
- Department of Neurosurgery, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India
| | - Ashima Nehra Wadhawan
- Department of Clinical Neuropsychology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India
| | - Ajay Garg
- Department of Neuroradiology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India
| | - Manjari Tripathi
- Department of Neurology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India.
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Wu X, Su Y, Liu W, Jia X, Zhang Y, Zhang X, Wang G. Diagnostic value and prognostic evaluation of dynamic video-electroencephalogram monitoring in children with epilepsy. Exp Ther Med 2017; 14:2527-2530. [PMID: 28962191 PMCID: PMC5609305 DOI: 10.3892/etm.2017.4822] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 07/14/2017] [Indexed: 12/15/2022] Open
Abstract
The diagnostic and prognostic value of dynamic video-electroencephalogram (V-EEG) monitoring in children with epilepsy were investigated. From February 2014 to February 2016, in total 200 children with epilepsy were selected during their stay in the First Hospital of Qinghuangdao and were randomly allocated to a dynamic and a conventional V-EEG monitoring group (n=100). The detection rate of epileptiform discharges in the two groups was evaluated. The V-EEG monitoring index was used to select treatment methods for patients with epilepsy. After 3 months, the patients were rechecked. Disease features and incidence of epilepsy were recorded. There were no significant differences in the course of disease, seizure frequency and age between the two groups (P>0.05). The detection rate of epileptiform discharges in the dynamic V-EEG was significantly higher than in the routine monitoring group (P<0.01). The accuracy and specificity of monitoring in the V-EEG were significantly higher than in the routine monitoring group (P<0.01). Seizure frequency and number of epilepsy attacks in patients in the V-EEG group were significantly lower than in the routine monitoring group (P<0.01). Dynamic V-EEG can improve epilepsy detection rate. The high accuracy and specificity of dynamic V-EEG suggest that it may be of great clinical value in the diagnosis and prognosis of epilepsy.
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Affiliation(s)
- Xiaobo Wu
- Department of Pediatrics, The First Hospital of Qinhuangdao, Qinhuangdao, Hebei 066000, P.R. China
| | - Ying Su
- Department of Pediatrics, The First Hospital of Qinhuangdao, Qinhuangdao, Hebei 066000, P.R. China
| | - Wei Liu
- Department of Pediatrics, The First Hospital of Qinhuangdao, Qinhuangdao, Hebei 066000, P.R. China
| | - Xiaoyu Jia
- Department of Pediatrics, The First Hospital of Qinhuangdao, Qinhuangdao, Hebei 066000, P.R. China
| | - Yanling Zhang
- Department of Pediatrics, The First Hospital of Qinhuangdao, Qinhuangdao, Hebei 066000, P.R. China
| | - Xinyang Zhang
- Department of Pediatrics, The First Hospital of Qinhuangdao, Qinhuangdao, Hebei 066000, P.R. China
| | - Guilan Wang
- Department of Pediatrics, The First Hospital of Qinhuangdao, Qinhuangdao, Hebei 066000, P.R. China
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Krámská L, Vojtěch Z, Lukavský J, Stará M, Malíková H. Five-Year Neuropsychological Outcome after Stereotactic Radiofrequency Amygdalohippocampectomy for Mesial Temporal Lobe Epilepsy: Longitudinal Study. Stereotact Funct Neurosurg 2017; 95:149-157. [DOI: 10.1159/000468527] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 03/02/2017] [Indexed: 11/19/2022]
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Cano-López I, Vázquez JF, Campos A, Gutiérrez A, Garcés M, Gómez-Ibáñez A, Conde R, González-Bono E, Villanueva V. Age at surgery as a predictor of cognitive improvements in patients with drug-resistant temporal epilepsy. Epilepsy Behav 2017; 70:10-17. [PMID: 28407524 DOI: 10.1016/j.yebeh.2017.03.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 12/16/2016] [Accepted: 03/04/2017] [Indexed: 10/19/2022]
Abstract
Temporal lobe epilepsy (TLE) surgery is an effective procedure that can produce cognitive changes. However, the prognostic factors related with cognitive outcomes need to be better understood. The aim of the present study is to know if age at surgery is a reliable predictor of verbal memory competence and considering factors such as: hemisphere; type of surgery; pre-surgical seizure frequency; and epilepsy duration. Sixty-one typically dominant patients with drug-resistant TLE (34 with left TLE [L-TLE] and 27 with right TLE [R-TLE]) underwent a neuropsychological assessment before and a year after surgery. Results showed that R-TLE patients had better evolution in short- and long-term verbal memory and naming than L-TLE patients (for all, p >.04). L-TLE patients also more frequently showed a strong and reliable decline in these functions than R-TLE patients. No effects for gender or type of surgery were found. From a multivariate approach, patients with improvements in verbal competence underwent surgery at earlier ages and suffered epilepsy for less time (for all, p <0.4). The relevance of age at surgery was confirmed as a predictor of long-term verbal memory changes, although the frequency of partial seizures also explains, at least partially, these changes. In addition, the frequency of partial seizures explains short-term verbal memory changes. These results emphasize the importance of early intervention, independently of the resected hemisphere, in order to minimize the cognitive side-effects of epilepsy treatment, as well the need to consider cognitive functions as related processes and network dependent.
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Affiliation(s)
- Irene Cano-López
- Department of Psychobiology/IDOCAL, University of Valencia, Spain; Multidisciplinary Epilepsy Unit/Neurology Service, Hospital Universitario y Politécnico La Fe, Spain
| | - Juan Francisco Vázquez
- Multidisciplinary Epilepsy Unit/Neurology Service, Hospital Universitario y Politécnico La Fe, Spain
| | - Anabel Campos
- Multidisciplinary Epilepsy Unit/Neurology Service, Hospital Universitario y Politécnico La Fe, Spain
| | - Antonio Gutiérrez
- Multidisciplinary Epilepsy Unit/Neurology Service, Hospital Universitario y Politécnico La Fe, Spain
| | - Mercedes Garcés
- Multidisciplinary Epilepsy Unit/Neurology Service, Hospital Universitario y Politécnico La Fe, Spain
| | - Asier Gómez-Ibáñez
- Multidisciplinary Epilepsy Unit/Neurology Service, Hospital Universitario y Politécnico La Fe, Spain
| | - Rebeca Conde
- Multidisciplinary Epilepsy Unit/Neurology Service, Hospital Universitario y Politécnico La Fe, Spain
| | | | - Vicente Villanueva
- Multidisciplinary Epilepsy Unit/Neurology Service, Hospital Universitario y Politécnico La Fe, Spain.
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Declarative long-term memory and the mesial temporal lobe: Insights from a 5-year postsurgery follow-up study on refractory temporal lobe epilepsy. Epilepsy Behav 2016; 64:102-109. [PMID: 27736656 DOI: 10.1016/j.yebeh.2016.08.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2016] [Revised: 08/29/2016] [Accepted: 08/31/2016] [Indexed: 11/22/2022]
Abstract
It is largely recognized that the mesial temporal lobe and its substructure support declarative long-term memory (LTM). So far, different theories have been suggested, and the organization of declarative verbal LTM in the brain is still a matter of debate. In the current study, we retrospectively selected 151 right-handed patients with temporal lobe epilepsy with and without hippocampal sclerosis, with a homogeneous (seizure-free) clinical outcome. We analyzed verbal memory performance within a normalized scores context, by means of prose recall and word paired-associate learning tasks. Patients were tested at presurgical baseline, 6months, 2 and 5years after anteromesial temporal lobe surgery, using parallel versions of the neuropsychological tests. Our main finding revealed a key involvement of the left temporal lobe and, in particular, of the left hippocampus in prose recall rather than word paired-associate task. We also confirmed that shorter duration of epilepsy, younger age, and withdrawal of antiepileptic drugs would predict a better memory outcome. When individual memory performance was taken into account, data showed that females affected by left temporal lobe epilepsy for longer duration were more at risk of presenting a clinically pathologic LTM at 5years after surgery. Taken together, these findings shed new light on verbal declarative memory in the mesial temporal lobe and on the behavioral signature of the functional reorganization after the surgical treatment of temporal lobe epilepsy.
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Grewe P, Nikstat A, Koch O, Koch-Stoecker S, Bien C. Subjective memory complaints in patients with epilepsy: The role of depression, psychological distress, and attentional functions. Epilepsy Res 2016; 127:78-86. [DOI: 10.1016/j.eplepsyres.2016.08.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 06/21/2016] [Accepted: 08/17/2016] [Indexed: 01/28/2023]
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Understanding Memory Systems in TLE: Networks, Nodes, and Hubs. Epilepsy Curr 2016; 16:153-5. [DOI: 10.5698/1535-7511-16.3.153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Sidhu MK, Stretton J, Winston GP, McEvoy AW, Symms M, Thompson PJ, Koepp MJ, Duncan JS. Memory network plasticity after temporal lobe resection: a longitudinal functional imaging study. Brain 2016; 139:415-30. [PMID: 26754787 PMCID: PMC4805088 DOI: 10.1093/brain/awv365] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 10/30/2015] [Indexed: 11/13/2022] Open
Abstract
Anterior temporal lobe resection can control seizures in up to 80% of patients with temporal lobe epilepsy. Memory decrements are the main neurocognitive complication. Preoperative functional reorganization has been described in memory networks, but less is known of postoperative reorganization. We investigated reorganization of memory-encoding networks preoperatively and 3 and 12 months after surgery. We studied 36 patients with unilateral medial temporal lobe epilepsy (19 right) before and 3 and 12 months after anterior temporal lobe resection. Fifteen healthy control subjects were studied at three equivalent time points. All subjects had neuropsychological testing at each of the three time points. A functional magnetic resonance imaging memory-encoding paradigm of words and faces was performed with subsequent out-of-scanner recognition assessments. Changes in activations across the time points in each patient group were compared to changes in the control group in a single flexible factorial analysis. Postoperative change in memory across the time points was correlated with postoperative activations to investigate the efficiency of reorganized networks. Left temporal lobe epilepsy patients showed increased right anterior hippocampal and frontal activation at both 3 and 12 months after surgery relative to preoperatively, for word and face encoding, with a concomitant reduction in left frontal activation 12 months postoperatively. Right anterior hippocampal activation 12 months postoperatively correlated significantly with improved verbal learning in patients with left temporal lobe epilepsy from preoperatively to 12 months postoperatively. Preoperatively, there was significant left posterior hippocampal activation that was sustained 3 months postoperatively at word encoding, and increased at face encoding. For both word and face encoding this was significantly reduced from 3 to 12 months postoperatively. Patients with right temporal lobe epilepsy showed increased left anterior hippocampal activation on word encoding from 3 to 12 months postoperatively compared to preoperatively. On face encoding, left anterior hippocampal activations were present preoperatively and 12 months postoperatively. Left anterior hippocampal and orbitofrontal cortex activations correlated with improvements in both design and verbal learning 12 months postoperatively. On face encoding, there were significantly increased left posterior hippocampal activations that reduced significantly from 3 to 12 months postoperatively. Postoperative changes occur in the memory-encoding network in both left and right temporal lobe epilepsy patients across both verbal and visual domains. Three months after surgery, compensatory posterior hippocampal reorganization that occurs is transient and inefficient. Engagement of the contralateral hippocampus 12 months after surgery represented efficient reorganization in both patient groups, suggesting that the contralateral hippocampus contributes to memory outcome 12 months after surgery.
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Affiliation(s)
- Meneka K Sidhu
- 1 Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK 2 Epilepsy Society MRI Unit, Chesham Lane, Chalfont St. Peter SL9 0RJ, Buckinghamshire, UK
| | - Jason Stretton
- 1 Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK 2 Epilepsy Society MRI Unit, Chesham Lane, Chalfont St. Peter SL9 0RJ, Buckinghamshire, UK 3 MRC Cognition and Brain Science Unit, Chaucer Road, Cambridge, CB2 7EF, UK
| | - Gavin P Winston
- 1 Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK 2 Epilepsy Society MRI Unit, Chesham Lane, Chalfont St. Peter SL9 0RJ, Buckinghamshire, UK
| | - Andrew W McEvoy
- 1 Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK 2 Epilepsy Society MRI Unit, Chesham Lane, Chalfont St. Peter SL9 0RJ, Buckinghamshire, UK
| | - Mark Symms
- 1 Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK 2 Epilepsy Society MRI Unit, Chesham Lane, Chalfont St. Peter SL9 0RJ, Buckinghamshire, UK
| | - Pamela J Thompson
- 1 Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK 2 Epilepsy Society MRI Unit, Chesham Lane, Chalfont St. Peter SL9 0RJ, Buckinghamshire, UK
| | - Matthias J Koepp
- 1 Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK 2 Epilepsy Society MRI Unit, Chesham Lane, Chalfont St. Peter SL9 0RJ, Buckinghamshire, UK
| | - John S Duncan
- 1 Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK 2 Epilepsy Society MRI Unit, Chesham Lane, Chalfont St. Peter SL9 0RJ, Buckinghamshire, UK
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Bernhardt BC, Bonilha L, Gross DW. Network analysis for a network disorder: The emerging role of graph theory in the study of epilepsy. Epilepsy Behav 2015; 50:162-70. [PMID: 26159729 DOI: 10.1016/j.yebeh.2015.06.005] [Citation(s) in RCA: 177] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 06/03/2015] [Accepted: 06/04/2015] [Indexed: 01/01/2023]
Abstract
Recent years have witnessed a paradigm shift in the study and conceptualization of epilepsy, which is increasingly understood as a network-level disorder. An emblematic case is temporal lobe epilepsy (TLE), the most common drug-resistant epilepsy that is electroclinically defined as a focal epilepsy and pathologically associated with hippocampal sclerosis. In this review, we will summarize histopathological, electrophysiological, and neuroimaging evidence supporting the concept that the substrate of TLE is not limited to the hippocampus alone, but rather is broadly distributed across multiple brain regions and interconnecting white matter pathways. We will introduce basic concepts of graph theory, a formalism to quantify topological properties of complex systems that has recently been widely applied to study networks derived from brain imaging and electrophysiology. We will discuss converging graph theoretical evidence indicating that networks in TLE show marked shifts in their overall topology, providing insight into the neurobiology of TLE as a network-level disorder. Our review will conclude by discussing methodological challenges and future clinical applications of this powerful analytical approach.
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Affiliation(s)
- Boris C Bernhardt
- Neuroimaging of Epilepsy Laboratory, Brain Imaging Center, Montreal Neurological Institute and Hospital, McGill University, Montreal, QC, Canada; Department of Social Neuroscience, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
| | - Leonardo Bonilha
- Department of Neurology, Medical University of South Carolina, SC, USA
| | - Donald W Gross
- Division of Neurology, Department of Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
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