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Cavaco S, Moreira B, Dias D, Gonçalves A, Pinto C, Almeida E, Gomes F, Moreira I, Chaves J, Lopes J, Ramalheira J, Freitas J, Samões R, Rangel R, Martins da Silva A. Auditory verbal learning test can lateralize hippocampal sclerosis. APPLIED NEUROPSYCHOLOGY. ADULT 2024; 31:932-938. [PMID: 35754382 DOI: 10.1080/23279095.2022.2090257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The ability of the Auditory Verbal Learning Test (AVLT) to lateralize hippocampal sclerosis (HS) in mesial temporal lobe epilepsy (MTLE) was explored in a sample of 50 patients with MTLE-HS (23 right and 27 left). Patients' AVLT scores were adjusted to the demographic characteristics of each individual in accordance with the Portuguese normative data. The laterality of the HS was determined by consensus by two neuroradiologists. ROC curves were used to identify the best AVLT cutoff scores to differentiate right vs. left HS. Diagnostic statistics were applied to different AVLT measures. The study results revealed that four AVLT scores can correctly classify the laterality of HS in the total sample and a sub-group of 39 right-handed patients (Edinburgh Laterality Inventory +100): delayed recall trial (76 and 80%, respectively), delayed recognition trial (64 and 67%, respectively), learning over trials index (64 and 74%, respectively), and long-term percent retention index (68 and 72%, respectively). In right-handed patients, the diagnostic capability of the delayed recall trial was improved by pairing it with the learning over trials index (accuracy of 85%). In sum, AVLT measures of verbal memory differentiate left from right HS in MTLE. The delayed recall trial demonstrated good diagnostic capacity.
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Affiliation(s)
- Sara Cavaco
- Neuropsychology Unit, Centro Hospitalar Universitario do Porto EPE, Porto, Portugal
- UMIB, Universidade do Porto Instituto de Ciencias Biomedicas Abel Salazar, Porto, Portugal
| | - Bruno Moreira
- Neuroradiology Department, Centro Hospitalar Universitario do Porto EPE, Porto, Portugal
| | - Daniel Dias
- Neuroradiology Department, Centro Hospitalar Universitario do Porto EPE, Porto, Portugal
| | - Alexandra Gonçalves
- Neuropsychology Unit, Centro Hospitalar Universitario do Porto EPE, Porto, Portugal
| | - Claudia Pinto
- Neuropsychology Unit, Centro Hospitalar Universitario do Porto EPE, Porto, Portugal
| | - Eduarda Almeida
- Neuropsychology Unit, Centro Hospitalar Universitario do Porto EPE, Porto, Portugal
| | - Filomena Gomes
- Neuropsychology Unit, Centro Hospitalar Universitario do Porto EPE, Porto, Portugal
| | - Inês Moreira
- Neuropsychology Unit, Centro Hospitalar Universitario do Porto EPE, Porto, Portugal
| | - João Chaves
- Neurology Department, Centro Hospitalar Universitario do Porto EPE, Porto, Portugal
| | - João Lopes
- Neurophysiology Department, Centro Hospitalar Universitario do Porto EPE, Porto, Portugal
| | - João Ramalheira
- Neurophysiology Department, Centro Hospitalar Universitario do Porto EPE, Porto, Portugal
| | - Joel Freitas
- Neurophysiology Department, Centro Hospitalar Universitario do Porto EPE, Porto, Portugal
| | - Raquel Samões
- Neurology Department, Centro Hospitalar Universitario do Porto EPE, Porto, Portugal
| | - Rui Rangel
- Department of Neurosurgery, Centro Hospitalar Universitario do Porto EPE, Porto, Portugal
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Zimmermann N, Pontes M, da Silva Fontana R, D'Andrea Meira I, Fonseca R, Delaere FJ. The modified Ruche visuospatial learning test (RUCHE-M) for the assessment of visuospatial episodic memory in patients with temporal lobe epilepsy: Preliminary evidence for the investigation of memory binding. APPLIED NEUROPSYCHOLOGY. ADULT 2024; 31:412-427. [PMID: 35133219 DOI: 10.1080/23279095.2022.2031200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
INTRODUCTION The Ruche test is a visuospatial form of the Rey auditory verbal learning test (RAVLT), with initial evidence of utility in the diagnosis of temporal lobe epilepsy (TLE)-related memory disorders. AIMS To present the translation to Brazilian Portuguese and modification of the Ruche test (RUCHE-M) and compare the RUCHE-M and RAVLT performance between patients with right and left TLE. METHODS Twenty-five neuropsychologists participated in instrument adaptation. Thirty-seven patients with right (n = 19) and left (n = 18) TLE participated. Data were compared with the Mann-Whitney U test. RESULTS All specialists considered the final RUCHE-M to be adequate. The RUCHE-M forgetting speed index (FSI) score and several RAVLT scores differed significantly between patients with right and left TLE. CONCLUSION The RUCHE-M showed limited utility for the assessment of visuospatial episodic memory in patients with TLE. The manipulation of memory binding as demonstrated by FSI score seems to be a promising paradigm for the assessment of right hippocampal function.
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Affiliation(s)
- Nicolle Zimmermann
- Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
- Paulo Niemeyer State Brain Institute, Rio de Janeiro, Brazil
| | - Monique Pontes
- Paulo Niemeyer State Brain Institute, Rio de Janeiro, Brazil
| | | | | | - Rochele Fonseca
- Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
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Duma GM, Danieli A, Mento G, Vitale V, Opipari RS, Jirsa V, Bonanni P, Sorrentino P. Altered spreading of neuronal avalanches in temporal lobe epilepsy relates to cognitive performance: A resting-state hdEEG study. Epilepsia 2023; 64:1278-1288. [PMID: 36799098 DOI: 10.1111/epi.17551] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 02/15/2023] [Accepted: 02/15/2023] [Indexed: 02/18/2023]
Abstract
OBJECTIVE Large aperiodic bursts of activations named neuronal avalanches have been used to characterize whole-brain activity, as their presence typically relates to optimal dynamics. Epilepsy is characterized by alterations in large-scale brain network dynamics. Here we exploited neuronal avalanches to characterize differences in electroencephalography (EEG) basal activity, free from seizures and/or interictal spikes, between patients with temporal lobe epilepsy (TLE) and matched controls. METHOD We defined neuronal avalanches as starting when the z-scored source-reconstructed EEG signals crossed a specific threshold in any region and ending when all regions returned to baseline. This technique avoids data manipulation or assumptions of signal stationarity, focusing on the aperiodic, scale-free components of the signals. We computed individual avalanche transition matrices to track the probability of avalanche spreading across any two regions, compared them between patients and controls, and related them to memory performance in patients. RESULTS We observed a robust topography of significant edges clustering in regions functionally and structurally relevant for the TLE, such as the entorhinal cortex, the inferior parietal and fusiform area, the inferior temporal gyrus, and the anterior cingulate cortex. We detected a significant correlation between the centrality of the entorhinal cortex in the transition matrix and the long-term memory performance (delay recall Rey-Osterrieth Complex Figure Test). SIGNIFICANCE Our results show that the propagation patterns of large-scale neuronal avalanches are altered in TLE during the resting state, suggesting a potential diagnostic application in epilepsy. Furthermore, the relationship between specific patterns of propagation and memory performance support the neurophysiological relevance of neuronal avalanches.
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Affiliation(s)
- Gian Marco Duma
- Epilepsy Unit, IRCCS E. Medea Scientific Institute, Treviso, Italy
| | - Alberto Danieli
- Epilepsy Unit, IRCCS E. Medea Scientific Institute, Treviso, Italy
| | - Giovanni Mento
- Department of General Psychology, University of Padova, Padova, Italy.,Padova Neuroscience Center (PNC), University of Padova, Padova, Italy
| | - Valerio Vitale
- Department of Neuroscience, Neuroradiology Unit, San Bortolo Hospital, Vicenza, Italy
| | | | - Viktor Jirsa
- Institut de Neurosciences des Systèmes, Aix-Marseille Université, Marseille, France
| | - Paolo Bonanni
- Epilepsy Unit, IRCCS E. Medea Scientific Institute, Treviso, Italy
| | - Pierpaolo Sorrentino
- Institut de Neurosciences des Systèmes, Aix-Marseille Université, Marseille, France
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Taube J, Witt JA, Grote A, Delev D, Enkirch J, Hattingen E, Becker AJ, Elger CE, Helmstaedter C. Preoperative and postoperative memory in epilepsy patients with 'gliosis only' versus hippocampal sclerosis: a matched case-control study. J Neurol Neurosurg Psychiatry 2022; 93:jnnp-2022-329224. [PMID: 36008114 DOI: 10.1136/jnnp-2022-329224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 08/14/2022] [Indexed: 11/03/2022]
Abstract
BACKGROUND Gliosis only (GO) and hippocampal sclerosis (HS) are distinct histopathological entities in mesial temporal lobe epilepsy. This study explores whether this distinction also exists on a functional level when evaluating pre- and postoperative memory. METHODS Using a retrospective matched case-control study design, we analysed verbal and visual memory performance in 49 patients with GO and 49 patients with HS before and one year after elective surgery. RESULTS Clinical differences were evident with a later age at seizure onset (18±12 vs 12±9 years) and fewer postoperative seizure-free patients in the GO group (63% vs 82%). Preoperatively, group and individual-level data demonstrated that memory impairments were less frequent, less severe and relatively non-specific in patients with GO compared with HS. Postoperatively, verbal memory declined in both groups, particularly after left-sided resections, with more significant losses in patients with GO. Factoring in floor effects, GO was also associated with more significant visual memory loss, particularly after left resections. CONCLUSIONS Compared with HS, GO is characterised by (1) a later onset of epilepsy, (2) less pronounced and more non-specific memory impairments before surgery, (3) a less successful surgical outcome and (4) a more significant memory decline after surgery. Overall, our results regarding cognition provide further evidence that GO and HS are distinct clinical entities. Functional integrity of the hippocampus appears higher in GO, as indicated by a better preoperative memory performance and worse memory outcome after surgery. The different risk-benefit ratios should be considered during presurgical patient counselling.
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Affiliation(s)
- Julia Taube
- Department of Epileptology, University Hospital Bonn, Bonn, Germany
| | | | - Alexander Grote
- Department of Neurosurgery, University of Marburg, Marburg, Germany
| | - Daniel Delev
- Clinic for Neurosurgery, University Medical Center Aachen, Aachen, Germany
| | - Jonas Enkirch
- Department of Neuroradiology, University Hospital Bonn, Bonn, Germany
| | - Elke Hattingen
- Institute of Neuroradiology, University Hospital Frankfurt, Goethe-University, Frankfurt am Main, Germany
| | - Albert J Becker
- Institute of Neuropathology, Section for Translational Epilepsy Research, University of Bonn, Medical Faculty, Bonn, Germany
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Taube J, Witt JA, Baumgartner T, Helmstaedter C. All’s well that ends well? Long-term course of a patient with anti-amphiphysin associated limbic encephalitis. Epilepsy Behav Rep 2022; 18:100534. [PMID: 35360257 PMCID: PMC8960971 DOI: 10.1016/j.ebr.2022.100534] [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: 09/23/2021] [Revised: 03/08/2022] [Accepted: 03/09/2022] [Indexed: 11/02/2022] Open
Abstract
Limbic encephalitis due to anti-amphiphysin antibodies can occur without a tumor. Amnesia, delirium, and seizures responded well to autoimmune and antiseizure therapy. Cognition recovered more slowly, behavioral problems persisted. Relapse is common and may even present with different clinical features. This case highlights the need for long-term multimodal monitoring.
Anti-amphiphysin associated limbic encephalitis (LE) is a paraneoplastic autoimmune disorder. The initial clinical presentation features seizures, cognitive and neuropsychiatric symptoms. We present the case of a 25-year-old female patient hospitalized after four consecutive tonic-clonic seizures, followed by confusion, psychotic symptoms, nonconvulsive seizure series, and severe global amnesia. Diagnostic workup revealed anti-amphiphysin associated LE without a tumor. MRI and PET indicated inflammatory processes affecting the bilateral mesial temporal structures more pronounced on the left side. Antiseizure medication, benzodiazepines, and immunotherapy resulted in rapid seizure cessation. Subsequent MRI and PET indicated left hippocampal sclerosis and a left mesial temporal hypometabolism. Executive dysfunction resolved in the following weeks. Global amnesia persisted for almost three months. Two years later, episodic memory was normal with residual visual memory impairments. While this patient’s seizure and cognitive outcome has been favorable, behavioral problems persisted long after disease onset. The persisting behavioral problems and subsequent MRI evidence (13 years after onset) of a swollen right amygdala indicated a possible relapse. This case report illustrates the importance of early diagnosis of LE for best clinical management. Antiseizure medication and immunotherapy led to seizure freedom and almost complete recovery of cognition. However, long-lasting neuropsychiatric symptoms and possible recurrent inflammation highlight the need for a multimodal long-term monitoring of such patients to rule out a relapse.
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Gleichgerrcht E, Munsell B, Keller SS, Drane DL, Jensen JH, Spampinato MV, Pedersen NP, Weber B, Kuzniecky R, McDonald C, Bonilha L. Radiological identification of temporal lobe epilepsy using artificial intelligence: a feasibility study. Brain Commun 2021; 4:fcab284. [PMID: 35243343 PMCID: PMC8887904 DOI: 10.1093/braincomms/fcab284] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 09/29/2021] [Accepted: 10/04/2021] [Indexed: 12/15/2022] Open
Abstract
Temporal lobe epilepsy is associated with MRI findings reflecting underlying mesial temporal sclerosis. Identifying these MRI features is critical for the diagnosis and management of temporal lobe epilepsy. To date, this process relies on visual assessment by highly trained human experts (e.g. neuroradiologists, epileptologists). Artificial intelligence is increasingly recognized as a promising aid in the radiological evaluation of neurological diseases, yet its applications in temporal lobe epilepsy have been limited. Here, we applied a convolutional neural network to assess the classification accuracy of temporal lobe epilepsy based on structural MRI. We demonstrate that convoluted neural networks can achieve high accuracy in the identification of unilateral temporal lobe epilepsy cases even when the MRI had been originally interpreted as normal by experts. We show that accuracy can be potentiated by employing smoothed grey matter maps and a direct acyclic graphs approach. We further discuss the foundations for the development of computer-aided tools to assist with the diagnosis of epilepsy.
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Affiliation(s)
- Ezequiel Gleichgerrcht
- Department of Neurology, Medical University of South
Carolina, Charleston, SC 29425, USA
| | - Brent Munsell
- Department of Computer Science, University of North
Carolina, Chapel Hill, NC 27599, USA
- Department of Psychiatry, University of North
Carolina, Chapel Hill, NC 27599, USA
| | - Simon S Keller
- Institute of Systems, Molecular and Integrative
Biology, University of Liverpool, Liverpool L69 7BE, UK
- The Walton Centre NHS Foundation
Trust, Liverpool L9 7LJ, UK
| | - Daniel L Drane
- Department of Neurology, Emory
University, Atlanta, GA 30322, USA
| | - Jens H Jensen
- Center for Biomedical Imaging, Medical University of
South Carolina, Charleston, SC 29425, USA
| | - M Vittoria Spampinato
- Department of Radiology, Medical University of South
Carolina, Charleston, SC 29425, USA
| | - Nigel P Pedersen
- Department of Neurology, Emory
University, Atlanta, GA 30322, USA
| | - Bernd Weber
- Institute of Experimental Epileptology and Cognition
Research, University of Bonn, Bonn 53113, Germany
| | - Ruben Kuzniecky
- Department of Neurology, Hofstra
University/Northwell, New York, NY 10075, USA
| | - Carrie McDonald
- Department of Psychiatry, University of California
San Diego, La Jolla, CA 92093, USA
| | - Leonardo Bonilha
- Department of Neurology, Medical University of South
Carolina, Charleston, SC 29425, USA
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Princich JP, Donnelly-Kehoe PA, Deleglise A, Vallejo-Azar MN, Pascariello GO, Seoane P, Veron Do Santos JG, Collavini S, Nasimbera AH, Kochen S. Diagnostic Performance of MRI Volumetry in Epilepsy Patients With Hippocampal Sclerosis Supported Through a Random Forest Automatic Classification Algorithm. Front Neurol 2021; 12:613967. [PMID: 33692740 PMCID: PMC7937810 DOI: 10.3389/fneur.2021.613967] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 01/18/2021] [Indexed: 01/07/2023] Open
Abstract
Introduction: Several methods offer free volumetry services for MR data that adequately quantify volume differences in the hippocampus and its subregions. These methods are frequently used to assist in clinical diagnosis of suspected hippocampal sclerosis in temporal lobe epilepsy. A strong association between severity of histopathological anomalies and hippocampal volumes was reported using MR volumetry with a higher diagnostic yield than visual examination alone. Interpretation of volumetry results is challenging due to inherent methodological differences and to the reported variability of hippocampal volume. Furthermore, normal morphometric differences are recognized in diverse populations that may need consideration. To address this concern, we highlighted procedural discrepancies including atlas definition and computation of total intracranial volume that may impact volumetry results. We aimed to quantify diagnostic performance and to propose reference values for hippocampal volume from two well-established techniques: FreeSurfer v.06 and volBrain-HIPS. Methods: Volumetry measures were calculated using clinical T1 MRI from a local population of 61 healthy controls and 57 epilepsy patients with confirmed unilateral hippocampal sclerosis. We further validated the results by a state-of-the-art machine learning classification algorithm (Random Forest) computing accuracy and feature relevance to distinguish between patients and controls. This validation process was performed using the FreeSurfer dataset alone, considering morphometric values not only from the hippocampus but also from additional non-hippocampal brain regions that could be potentially relevant for group classification. Mean reference values and 95% confidence intervals were calculated for left and right hippocampi along with hippocampal asymmetry degree to test diagnostic accuracy. Results: Both methods showed excellent classification performance (AUC:> 0.914) with noticeable differences in absolute (cm3) and normalized volumes. Hippocampal asymmetry was the most accurate discriminator from all estimates (AUC:1~0.97). Similar results were achieved in the validation test with an automatic classifier (AUC:>0.960), disclosing hippocampal structures as the most relevant features for group differentiation among other brain regions. Conclusion: We calculated reference volumetry values from two commonly used methods to accurately identify patients with temporal epilepsy and hippocampal sclerosis. Validation with an automatic classifier confirmed the principal role of the hippocampus and its subregions for diagnosis.
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Affiliation(s)
- Juan Pablo Princich
- ENyS (Estudios en Neurociencias y Sistemas Complejos), Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional Arturo Jauretche y Hospital El Cruce, Florencio Varela, Argentina.,Hospital de Pediatría J.P Garrahan, Departamento de Neuroimágenes, Buenos Aires, Argentina
| | - Patricio Andres Donnelly-Kehoe
- Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas (CIFASIS) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Grupo de Procesamiento de Señales Multimedia - División Neuroimágenes, Universidad Nacional de Rosario, Rosario, Argentina
| | - Alvaro Deleglise
- Instituto de Fisiología y Biofísica B. Houssay (IFIBIO), Consejo Nacional de Investigaciones Científicas y Técnicas, Departamento de Fisiología y Biofísica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Mariana Nahir Vallejo-Azar
- ENyS (Estudios en Neurociencias y Sistemas Complejos), Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional Arturo Jauretche y Hospital El Cruce, Florencio Varela, Argentina
| | - Guido Orlando Pascariello
- Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas (CIFASIS) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Grupo de Procesamiento de Señales Multimedia - División Neuroimágenes, Universidad Nacional de Rosario, Rosario, Argentina
| | - Pablo Seoane
- ENyS (Estudios en Neurociencias y Sistemas Complejos), Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional Arturo Jauretche y Hospital El Cruce, Florencio Varela, Argentina.,Hospital J.M Ramos Mejía, Centro de Epilepsia, Buenos Aires, Argentina
| | - Jose Gabriel Veron Do Santos
- ENyS (Estudios en Neurociencias y Sistemas Complejos), Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional Arturo Jauretche y Hospital El Cruce, Florencio Varela, Argentina
| | - Santiago Collavini
- ENyS (Estudios en Neurociencias y Sistemas Complejos), Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional Arturo Jauretche y Hospital El Cruce, Florencio Varela, Argentina.,Instituto de investigación en Electrónica, Control y Procesamiento de Señales (LEICI), Universidad Nacional de La Plata-Consejo Nacional de Investigaciones Científicas y Técnicas, La Plata, Argentina.,Instituto de Ingeniería y Agronomía, Universidad Nacional Arturo Jauretche, Florencio Varela, Argentina
| | - Alejandro Hugo Nasimbera
- ENyS (Estudios en Neurociencias y Sistemas Complejos), Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional Arturo Jauretche y Hospital El Cruce, Florencio Varela, Argentina.,Hospital J.M Ramos Mejía, Centro de Epilepsia, Buenos Aires, Argentina
| | - Silvia Kochen
- ENyS (Estudios en Neurociencias y Sistemas Complejos), Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional Arturo Jauretche y Hospital El Cruce, Florencio Varela, Argentina
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Typical visual unfamiliar face individuation in left and right mesial temporal epilepsy. Neuropsychologia 2020; 147:107583. [PMID: 32771474 DOI: 10.1016/j.neuropsychologia.2020.107583] [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: 04/23/2020] [Revised: 07/07/2020] [Accepted: 08/05/2020] [Indexed: 12/14/2022]
Abstract
Patients with chronic mesial temporal lobe epilepsy have difficulties at identifying familiar faces as well as at explicit old/new face recognition tasks. However, the extent to which these difficulties can be attributed to visual individuation of faces, independently of general explicit learning and semantic memory processes, is unknown. We tested 42 mesial temporal lobe epilepsy patients divided into two groups according to the side of epilepsy (left and right) and 42 matched controls on an extensive series of individuation tasks of unfamiliar faces and control visual stimuli, as well as on face detection, famous face recognition and naming, and face and non-face learning. Overall, both patient groups had difficulties at identifying and naming famous faces, and at explicitly learning face and non-face images. However, there was no group difference in accuracy between patients and controls at the two most widely used neuropsychological tests assessing visual individuation of unfamiliar faces (Benton Facial Recognition Test and Cambridge Face Memory Test). While patients with right mesial temporal lobe epilepsy were slowed down at all tasks, this effect was not specific to faces or even high-level stimuli. Importantly, both groups showed the same profile of response as typical participants across various stimulus manipulations, showing no evidence of qualitative processing impairments. Overall, these results point to largely preserved visual face individuation processes in patients with mesial temporal lobe epilepsy, with semantic and episodic memory difficulties being consistent with the localization of the neural structures involved in their epilepsy (anterior temporal cortex and hippocampus). These observations have implications for the prediction of neuropsychological outcomes in the case of surgery and support the validity of intracranial electroencephalographic recordings performed in this population to understand neural mechanisms of human face individuation, notably through intracranial electrophysiological recordings and stimulations.
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