1
|
Mazzacane F, Ferrari F, Malvaso A, Mottese Y, Gastaldi M, Costa A, Pichiecchio A, Cavallini A. Acute amnestic syndrome in fornix lesions: a systematic review of reported cases with a focus on differential diagnosis. Front Neurol 2024; 15:1338291. [PMID: 38333604 PMCID: PMC10850356 DOI: 10.3389/fneur.2024.1338291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Accepted: 01/09/2024] [Indexed: 02/10/2024] Open
Abstract
Introduction Acute amnestic syndrome is an uncommon clinical presentation of neurological disease. Differential diagnosis encompasses several syndromes including Wernicke-Korsakoff and transient global amnesia (TGA). Structural lesions of the fornix account for a minority of cases of acute amnestic syndromes. Etiology varies from iatrogenic injury to ischemic, inflammatory, or neoplastic lesions. A prompt diagnosis of the underlying pathology is essential but challenging. The aim of this review is to systematically review the existing literature regarding cases of acute amnestic syndrome associated with non-iatrogenic lesions of the fornix. Methods We performed a systematic literature search on PubMed, Scopus, and Web of Science up to September 2023 to identify case reports and case series of patients with amnestic syndrome due to fornix lesions. The systematic review was conducted according to PRISMA guidelines. The research was limited to articles written in English. Cases of fornix damage directly ascribable to a surgical procedure were excluded. Results A total of 52 publications reporting 55 cases were included in the review. Focusing on acute/subacute onset, vascular etiology was highly prevalent, being responsible for 78% of cases, 40/55 (74%) of which were due to acute ischemic stroke. The amnestic syndrome was characterized by anterograde amnesia in all patients, associated with retrograde amnesia in 27% of cases. Amnesia was an isolated presentation in most cases. Up to two thirds of patients had persistent memory deficits of any severity at follow-up. Discussion Acute amnestic syndrome can be rarely caused by fornix lesions. In most cases of acute/subacute presentation, the etiology is ischemic stroke, mainly caused by strokes involving the subcallosal artery territory. The differential diagnosis is challenging and a distinction from common mimics is often difficult on a clinical basis. A high index of suspicion should be maintained to avoid misdiagnosis and provide adequate acute treatment to patients with time-dependent disease, also employing advanced neuroimaging. More research is needed to better understand the outcome and identify prognostic factors in patients with amnestic syndrome due to fornix lesions.
Collapse
Affiliation(s)
- F. Mazzacane
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
- Department of Emergency Neurology and Stroke Unit, IRCCS Fondazione Mondino, Pavia, Italy
- Unit of Behavioral Neurology, Mondino Foundation, Pavia, Italy
| | - F. Ferrari
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
- Department of Emergency Neurology and Stroke Unit, IRCCS Fondazione Mondino, Pavia, Italy
| | - A. Malvaso
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
- Neuroimmunology Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - Y. Mottese
- Department of Neuroradiology, IRCCS Mondino Foundation, Pavia, Italy
| | - M. Gastaldi
- Neuroimmunology Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - A. Costa
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
- Unit of Behavioral Neurology, Mondino Foundation, Pavia, Italy
| | - A. Pichiecchio
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy
- Department of Neuroradiology, IRCCS Mondino Foundation, Pavia, Italy
| | - A. Cavallini
- Department of Emergency Neurology and Stroke Unit, IRCCS Fondazione Mondino, Pavia, Italy
| |
Collapse
|
2
|
Rodini M, De Simone MS, Caltagirone C, Carlesimo GA. Accelerated long-term forgetting in neurodegenerative disorders: A systematic review of the literature. Neurosci Biobehav Rev 2022; 141:104815. [PMID: 35961382 DOI: 10.1016/j.neubiorev.2022.104815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 07/29/2022] [Accepted: 08/01/2022] [Indexed: 11/19/2022]
Abstract
Accelerated Long-term Forgetting (ALF) is a memory deficit characterised by normal retention up to relatively short intervals (e.g., minutes, hours) with increased forgetting over longer periods (e.g., days, weeks). ALF is often underestimated due to a lack of common memory assessments beyond 30-60 min. The purpose of this review was to provide an overview of ALF occurrence in neurodegenerative disorders, evaluating whether it can be considered a cognitive deficit useful for diagnosing and monitoring patients. We included 19 experimental studies that investigated ALF in neurodegenerative disorders. Most papers were focused on Alzheimer's disease (AD) dementia and related forms of cognitive decline (Mild Cognitive Impairment, Subjective Cognitive decline, Pre-symptomatic subjects at risk of AD dementia). The major finding of the present work concerns the presence of ALF in very early forms of cognitive decline related to AD. These findings, supporting the hypothesis that ALF is a subtle and undetected hallmark of pre-clinical AD, highlights the importance of investigating forgetting over a longer period and devising standardised measures to be included in clinical practice.
Collapse
Affiliation(s)
- Marta Rodini
- Laboratory of Neuropsychology of Memory, Department of Clinical and Behavioural Neurology, Santa Lucia Foundation IRCCS, Rome, Italy.
| | - Maria Stefania De Simone
- Laboratory of Neuropsychology of Memory, Department of Clinical and Behavioural Neurology, Santa Lucia Foundation IRCCS, Rome, Italy
| | - Carlo Caltagirone
- Laboratory of Neuropsychology of Memory, Department of Clinical and Behavioural Neurology, Santa Lucia Foundation IRCCS, Rome, Italy
| | - Giovanni Augusto Carlesimo
- Laboratory of Neuropsychology of Memory, Department of Clinical and Behavioural Neurology, Santa Lucia Foundation IRCCS, Rome, Italy; Department of Systems Medicine, Tor Vergata University, Rome, Italy
| |
Collapse
|
3
|
Miller TD, Butler CR. Acute-onset amnesia: transient global amnesia and other causes. Pract Neurol 2022; 22:201-208. [PMID: 35504698 DOI: 10.1136/practneurol-2020-002826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2022] [Indexed: 11/04/2022]
Abstract
Acute-onset amnesia is a dramatic neurological presentation that can cause considerable concern to both patient and clinician. The patient typically presents with an inability not only to retain new memories but also to access previously acquired memories, suggesting disturbance of hippocampal function. Transient global amnesia (TGA) is the most common cause of acute-onset amnesia, and is characterised by a profound anterograde and retrograde amnesia that typically lasts for up to 24 hours. Although TGA has a strikingly stereotypical presentation, it can be challenging to distinguish from other causes of acute-onset amnesia, including posterior circulation strokes, transient epileptic amnesia, psychogenic amnesia, post-traumatic amnesia, and toxic/drug-related amnesia. Here, we describe the general approach to the patient with acute amnesia; summarise the clinical and neuropsychological differences between the potential causes; and, provide practical recommendations to aid diagnosis and management of acute amnesia. Regardless of cause and the dramatic presentation, non-ischaemic acute-onset amnesia generally has a favourable prognosis.
Collapse
Affiliation(s)
- Thomas D Miller
- Wellcome Centre for Human Neuroimaging, UCL Queen Square Institute of Neurology, London, UK .,National Hospital for Neurology and Neurosurgery, London, UK
| | | |
Collapse
|
4
|
Transient epileptic amnesia is significantly associated with discrete CA1-located hippocampal calcifications but not with atrophic changes on brain imaging. Epilepsy Res 2021; 176:106736. [PMID: 34403990 DOI: 10.1016/j.eplepsyres.2021.106736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 07/17/2021] [Accepted: 08/05/2021] [Indexed: 11/24/2022]
Abstract
BACKGROUND The exact etiology of transient epileptic amnesia (TEA) is currently unknown. In older individuals, common neurodegenerative dementias and small-vessel diseases (SVDs) could be major contributors. We examined these hypotheses on the basis of imaging analysis. METHODS In total, 36 TEA patients were compared with 25 healthy controls for (1) cortical atrophic changes (in the mesial temporal, frontal, anterior temporal, and parietal regions) using four established MRI-based visual rating scales, and for (2) SVD evidence using two MRI-based visual rating scales (Fazekas and MARS scores). In 24 TEAs cases, there were also brain CT scans available that were compared with 57 controls for the presence of hippocampal calcifications (HCs). RESULTS We did not find significant differences in cortical atrophy between TEAs and controls, nor did we observe a different SVD brain load on MRI. However, TEAs were significantly associated (p < 0.01) with uni- or bilateral CA1-located HCs in half of the patients compared with the controls (less than 20 %). CONCLUSIONS This study argues in favor of a hippocampal-restricted SVD (as indicated by HCs) as one of the major etiologies of TEA, while neurodegenerative dementias are probably minor causes. It furthermore highlights the pivotal role of the CA1 hippocampal subfield in the pathophysiology of this syndrome.
Collapse
|
5
|
McGinty RN, Larner AJ. Transient epileptic amnesia and pathological tearfulness. Cortex 2021; 147:206-208. [PMID: 34148639 DOI: 10.1016/j.cortex.2021.05.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 05/17/2021] [Accepted: 05/18/2021] [Indexed: 11/03/2022]
Affiliation(s)
- Ronan N McGinty
- Cognitive Function Clinic, Walton Centre for Neurology and Neurosurgery, Liverpool, United Kingdom
| | - Andrew J Larner
- Cognitive Function Clinic, Walton Centre for Neurology and Neurosurgery, Liverpool, United Kingdom.
| |
Collapse
|
6
|
Accelerated forgetting in temporal lobe epilepsy: When does it occur? Cortex 2021; 141:190-200. [PMID: 34058619 DOI: 10.1016/j.cortex.2021.03.035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 02/24/2021] [Accepted: 03/30/2021] [Indexed: 11/21/2022]
Abstract
OBJECTIVE The main goal of the study was to analyse differences in the forgetting rates of Temporal Lobe Epilepsy (TLE) patients at different intervals (30 sec, 10 min, 1 day and 1 week) compared with those of healthy controls. A secondary aim of this research was to provide an assessment of the relationship between clinical epilepsy-related variables and forgetting rates in TLE patients. METHOD The sample was composed of 14 TLE patients and 14 healthy matched controls. All participants underwent a full standardised neuropsychological assessment including general intelligence, executive functioning, memory, language and other variables, such as depression, anxiety or everyday memory failures. Two specific memory tasks, consisting of cued recall of 4 short stories and 4 routes, were carried out at four different intervals. RESULTS There was a significant difference between groups at 10-min interval on the stories task, with the TLE group displaying greater forgetting than healthy controls. None of the other intervals on either task showed significant group differences. No differences were found when controlling for clinical epilepsy-related variables. CONCLUSION Forgetting of verbal information at 10 min was greater in patients with TLE compared with controls, but accelerated longer term forgetting was not found. This study suggests that a late consolidation process is not necessarily impaired in TLE patients.
Collapse
|
7
|
Baker J, Savage S, Milton F, Butler C, Kapur N, Hodges J, Zeman A. The syndrome of transient epileptic amnesia: a combined series of 115 cases and literature review. Brain Commun 2021; 3:fcab038. [PMID: 33884371 PMCID: PMC8047097 DOI: 10.1093/braincomms/fcab038] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 01/26/2021] [Accepted: 01/28/2021] [Indexed: 12/24/2022] Open
Abstract
The term transient epileptic amnesia was coined in 1990 to describe a form of epilepsy causing predominantly amnestic seizures which could be confused with episodes of Transient Global Amnesia. Subsequent descriptions have highlighted its association with ‘atypical’ forms of memory disturbance including accelerated long-term forgetting, disproportionate autobiographical amnesia and topographical amnesia. However, this highly treatment-responsive condition remains under-recognized and undertreated. We describe the clinical and neuropsychological features in 65 consecutive cases of transient epileptic amnesia referred to our study, comparing these to our previous cohort of 50 patients and to those reported in 102 literature cases described since our 2008 review. Findings in our two cohorts are substantially consistent: The onset of transient epileptic amnesia occurs at an average age of 62 years, giving rise to amnestic episodes at a frequency of around 1/month, typically lasting 15–30 min and often occurring on waking. Amnesia is the only manifestation of epilepsy in 24% of patients; olfactory hallucinations occur in 43%, motor automatisms in 41%, brief unresponsiveness in 39%. The majority of patients describe at least one of the atypical forms of memory disturbance mentioned above; easily provoked tearfulness is a common accompanying feature. There is a male predominance (85:30). Epileptiform changes were present in 35% of cases, while suspected causative magnetic resonance imaging abnormalities were detected in only 5%. Seizures ceased with anticonvulsant treatment in 93% of cases. Some clinical features were detected more commonly in the second series than the first, probably as a result of heightened awareness. Neuropsychological testing and comparison to two age and IQ-matched control groups (n = 24 and 22) revealed consistent findings across the two cohorts, namely elevated mean IQ, preserved executive function, mild impairment at the group level on standard measures of memory, with additional evidence for accelerated long-term forgetting and autobiographical amnesia, particularly affecting episodic recollection. Review of the literature cases revealed broadly consistent features except that topographical amnesia, olfactory hallucinations and emotionality have been reported rarely to date by other researchers. We conclude that transient epileptic amnesia is a distinctive syndrome of late-onset limbic epilepsy of unknown cause, typically occurring in late middle age. It is an important, treatable cause of memory loss in older people, often mistaken for dementia, cerebrovascular disease and functional amnesia. Its aetiology, the monthly occurrence of seizures in some patients and the mechanisms and interrelationships of the interictal features—amnestic and affective—all warrant further study.
Collapse
Affiliation(s)
- John Baker
- Cognitive & Behavioural Neurology, University of Exeter Medical School, College House, St Luke's Campus, Exeter EX1 2LU, UK
| | - Sharon Savage
- Cognitive & Behavioural Neurology, University of Exeter Medical School, College House, St Luke's Campus, Exeter EX1 2LU, UK.,School of Psychology, University of Newcastle, New South Wales 2308, Australia
| | - Fraser Milton
- Discipline of Psychology, University of Exeter, Washington Singer Laboratories, Exeter EX4 4QG, UK
| | - Christopher Butler
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK.,Department of Brain Sciences, Imperial College, London W12 0NN, UK.,Departamento de Neurología, Pontificia Universidad Católica de Chile, Santiago 833007, Chile
| | - Narinder Kapur
- Research Department of Clinical, Educational and Health Psychology, University College London, London WC1E 6BT, UK
| | - John Hodges
- Brain and Mind Centre, University of Sydney, Sydney 2050, Australia
| | - Adam Zeman
- Cognitive & Behavioural Neurology, University of Exeter Medical School, College House, St Luke's Campus, Exeter EX1 2LU, UK
| |
Collapse
|
8
|
A Review of Accelerated Long-Term Forgetting in Epilepsy. Brain Sci 2020; 10:brainsci10120945. [PMID: 33297371 PMCID: PMC7762289 DOI: 10.3390/brainsci10120945] [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: 11/09/2020] [Revised: 11/30/2020] [Accepted: 12/03/2020] [Indexed: 11/16/2022] Open
Abstract
Accelerated long-term forgetting (ALF) is a memory disorder that manifests by a distinct pattern of normal memory for up to an hour after learning, but an increased rate of forgetting during the subsequent hours and days. The topic of ALF has gained much attention in group studies with epilepsy patients and the phenomenon has been shown to have contradictory associations with seizures, epileptiform activity, imaging data, sleep, and antiepileptic medication. The aim of this review was to explore how clinical and imaging data could help determine the topographic and physiological substrate of ALF, and what is the possible use of this information in the clinical setting. We have reviewed 51 group studies in English to provide a synthesis of the existing findings concerning ALF in epilepsy. Analysis of recently reported data among patients with temporal lobe epilepsy, transient epileptic amnesia, and generalized and extratemporal epilepsies provided further indication that ALF is likely a disorder of late memory consolidation. The spatial substrate of ALF might be located along the parts of the hippocampal-neocortical network and novel studies reveal the increasingly possible importance of damage in extrahippocampal sites. Further research is needed to explore the mechanisms of cellular impairment in ALF and to develop effective methods of care for patients with the disorder.
Collapse
|
9
|
Yaakub SN, Heckemann RA, Keller SS, McGinnity CJ, Weber B, Hammers A. On brain atlas choice and automatic segmentation methods: a comparison of MAPER & FreeSurfer using three atlas databases. Sci Rep 2020; 10:2837. [PMID: 32071355 PMCID: PMC7028906 DOI: 10.1038/s41598-020-57951-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 11/27/2019] [Indexed: 11/09/2022] Open
Abstract
Several automatic image segmentation methods and few atlas databases exist for analysing structural T1-weighted magnetic resonance brain images. The impact of choosing a combination has not hitherto been described but may bias comparisons across studies. We evaluated two segmentation methods (MAPER and FreeSurfer), using three publicly available atlas databases (Hammers_mith, Desikan-Killiany-Tourville, and MICCAI 2012 Grand Challenge). For each combination of atlas and method, we conducted a leave-one-out cross-comparison to estimate the segmentation accuracy of FreeSurfer and MAPER. We also used each possible combination to segment two datasets of patients with known structural abnormalities (Alzheimer's disease (AD) and mesial temporal lobe epilepsy with hippocampal sclerosis (HS)) and their matched healthy controls. MAPER was better than FreeSurfer at modelling manual segmentations in the healthy control leave-one-out analyses in two of the three atlas databases, and the Hammers_mith atlas database transferred to new datasets best regardless of segmentation method. Both segmentation methods reliably identified known abnormalities in each patient group. Better separation was seen for FreeSurfer in the AD and left-HS datasets, and for MAPER in the right-HS dataset. We provide detailed quantitative comparisons for multiple anatomical regions, thus enabling researchers to make evidence-based decisions on their choice of atlas and segmentation method.
Collapse
Affiliation(s)
- Siti Nurbaya Yaakub
- King's College London & Guy's and St Thomas' PET Centre, School of Biomedical Engineering & Imaging Sciences, King's College London, London, United Kingdom
| | - Rolf A Heckemann
- MedTech West at Sahlgrenska University Hospital Gothenburg, Gothenburg, Sweden
- Department of Radiation Physics, Institute of Clinical Sciences, Gothenburg University, Gothenburg, Sweden
- Division of Brain Sciences, Imperial College London, London, United Kingdom
| | - Simon S Keller
- Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
- Department of Neuroradiology, The Walton Centre NHS Foundation Trust, Liverpool, United Kingdom
| | - Colm J McGinnity
- King's College London & Guy's and St Thomas' PET Centre, School of Biomedical Engineering & Imaging Sciences, King's College London, London, United Kingdom
| | - Bernd Weber
- Center for Economics and Neuroscience, University of Bonn, Bonn, Germany
- Institute of Experimental Epileptology and Cognition Research, University Hospital Bonn, Bonn, Germany
| | - Alexander Hammers
- King's College London & Guy's and St Thomas' PET Centre, School of Biomedical Engineering & Imaging Sciences, King's College London, London, United Kingdom.
| |
Collapse
|
10
|
Polat B, Yılmaz NH, Mantar N, Cadirci F, Sitrava S, Ozmansur EN, Uzan M, Özkara C, Hanoglu L. Accelerated long-term forgetting after amygdalohippocampectomy in temporal lobe epilepsy. J Clin Neurosci 2020; 72:43-49. [PMID: 31956086 DOI: 10.1016/j.jocn.2020.01.038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Accepted: 01/05/2020] [Indexed: 10/25/2022]
|
11
|
Ramanan VK, Morris KA, Graff-Radford J, Jones DT, Burkholder DB, Britton JW, Josephs KA, Boeve BF, Savica R. Transient Epileptic Amnesia: A Treatable Cause of Spells Associated With Persistent Cognitive Symptoms. Front Neurol 2019; 10:939. [PMID: 31555199 PMCID: PMC6724577 DOI: 10.3389/fneur.2019.00939] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 08/13/2019] [Indexed: 11/21/2022] Open
Abstract
Objective: To characterize the clinical, EEG, and neuroimaging profiles of transient epileptic amnesia (TEA). Methods: We performed a retrospective analysis of patients diagnosed with TEA at the Mayo Clinic Minnesota from January 1, 1998 to September 21, 2017. Diagnostic criteria included the presence of recurrent episodes of transient amnesia with preservation of other cognitive functions and evidence for epilepsy [epileptiform abnormalities on EEG, clinical features of seizures, or symptomatic response to anti-seizure medications (ASMs)]. Results: Nineteen patients were identified (14 men, 5 women) with median onset age 66 years and median time to diagnosis 2 years. Thirteen patients (68%) reported persistent cognitive/behavioral symptoms, including 4 (21%) for whom these were the chief presenting complaints. EEG revealed epileptiform abnormalities involving the frontal and/or temporal regions in 12/19 individuals (63%), including activation during sleep in all of these cases. In numerous cases, sleep and prolonged EEG evaluations identified abnormalities not previously seen on shorter or awake-state studies. Brain MRI revealed focal abnormalities in only 4/19 cases (21%). FDG-PET identified focal hypometabolism in 2/8 cases where it was performed, both involving the frontal and/or temporal regions. Anti-seizure therapy, most often with a single agent, resulted in improvement (reduction in spell frequency and/or subjective improvement in interictal cognitive/behavioral complaints) in all 17 cases with available follow-up. Conclusions: TEA is a treatable cause of amnestic spells in older adults. This syndrome is frequently associated with persistent interictal cognitive/behavioral symptoms and thus can be mistaken for common mimics. In the appropriate clinical context, our findings support the use of early prolonged EEG with emphasis on sleep monitoring as a key diagnostic tool. FDG-PET may also complement MRI in distinguishing TEA from neurodegenerative disease when suspected.
Collapse
Affiliation(s)
- Vijay K Ramanan
- Department of Neurology, Mayo Clinic-Rochester, Rochester, MN, United States
| | - Kenneth A Morris
- Department of Neurology, Mayo Clinic-Rochester, Rochester, MN, United States
| | | | - David T Jones
- Department of Neurology, Mayo Clinic-Rochester, Rochester, MN, United States
| | - David B Burkholder
- Department of Neurology, Mayo Clinic-Rochester, Rochester, MN, United States
| | - Jeffrey W Britton
- Department of Neurology, Mayo Clinic-Rochester, Rochester, MN, United States
| | - Keith A Josephs
- Department of Neurology, Mayo Clinic-Rochester, Rochester, MN, United States
| | - Bradley F Boeve
- Department of Neurology, Mayo Clinic-Rochester, Rochester, MN, United States
| | - Rodolfo Savica
- Department of Neurology, Mayo Clinic-Rochester, Rochester, MN, United States
| |
Collapse
|
12
|
Abstract
PURPOSE OF REVIEW This article reviews the current understanding of memory system anatomy and physiology, as well as relevant evaluation methods and pathologic processes. RECENT FINDINGS Our understanding of memory formation advances each year. Successful episodic memory formation depends not only on intact medial temporal lobe structures but also on well-orchestrated interactions with other large-scale brain networks that support executive and semantic processing functions. Recent discoveries of cognitive control networks have helped in understanding the interaction between memory systems and executive systems. These interactions allow access to past experiences and enable comparisons between past experiences and external and internal information. The semantic memory system is less clearly defined anatomically. Anterior, lateral, and inferior temporal lobe regions appear to play a crucial role in the function of the semantic processing system. Different but tightly interconnected cortical regions, such as the prefrontal region, may play a controlling role in this system. The presentation of clinical disease affecting memory is the result of the selective vulnerability of the memory system. An understanding of current concepts of memory anatomy, physiology, and evaluation plays a central role in establishing an accurate diagnosis. SUMMARY Different memory systems rely on separate but overlapping distributed brain networks. Certain pathologic processes preferentially affect memory systems. An understanding of memory formation stages will enable more accurate diagnosis.
Collapse
|
13
|
Audrain S, McAndrews MP. Cognitive and functional correlates of accelerated long-term forgetting in temporal lobe epilepsy. Cortex 2019; 110:101-114. [DOI: 10.1016/j.cortex.2018.03.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 12/24/2017] [Accepted: 03/19/2018] [Indexed: 02/07/2023]
|
14
|
Helmstaedter C, Winter B, Melzer N, Lohmann H, Witt JA. Accelerated long-term forgetting in focal epilepsies with special consideration given to patients with diagnosed and suspected limbic encephalitis. Cortex 2019; 110:58-68. [DOI: 10.1016/j.cortex.2018.01.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Revised: 07/13/2017] [Accepted: 01/05/2018] [Indexed: 02/04/2023]
|
15
|
Holley AJ, Hodges SL, Nolan SO, Binder M, Okoh JT, Ackerman K, Tomac LA, Lugo JN. A single seizure selectively impairs hippocampal-dependent memory and is associated with alterations in PI3K/Akt/mTOR and FMRP signaling. Epilepsia Open 2018; 3:511-523. [PMID: 30525120 PMCID: PMC6276778 DOI: 10.1002/epi4.12273] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/18/2018] [Indexed: 02/03/2023] Open
Abstract
Objective A single brief seizure before learning leads to spatial and contextual memory impairment in rodents without chronic epilepsy. These results suggest that memory can be impacted by seizure activity in the absence of epilepsy pathology. In this study, we investigated the types of memory affected by a seizure and the time course of impairment. We also examined alterations to mammalian target of rapamycin (mTOR) and fragile X mental retardation protein (FMRP) signaling, which modulate elements of the synapse and may underlie impairment. Methods We induced a single seizure and investigated hippocampal and nonhippocampal memory using trace fear conditioning, novel object recognition (NOR), and accelerating rotarod to determine the specificity of impairment in mice. We used western blot analysis to examine for changes to cellular signaling and synaptic proteins 1 h, 24 h, and 1 week after a seizure. We also included a histologic examination to determine if cell loss or gross lesions might alternatively explain memory deficits. Results Behavioral results indicated that a seizure before learning leads to impairment of trace fear memory that worsens over time. In contrast, nonhippocampal memory was unaffected by a seizure in the NOR and rotarod tasks. Western analysis indicated increased hippocampal phospho‐S6 and total FMRP 1 h following a seizure. Tissue taken 24 h after a seizure indicated increased hippocampal GluA1, suggesting increased α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid (AMPA) receptor expression. Histologic analysis indicated that neither cell loss nor lesions are present after a single seizure. Significance The presence of memory impairment in the absence of damage suggests that memory impairment caused by seizure activity differs from general memory impairment in epilepsy. Instead, memory impairment after a single seizure is associated with alterations to mTOR and FMRP signaling, which leads to a disruption of synaptic proteins involved in consolidation of long‐term memory. These results have implications for understanding memory impairment in epilepsy.
Collapse
Affiliation(s)
- Andrew J Holley
- Department of Psychology and Neuroscience Baylor University Waco Texas U.S.A
| | | | - Suzanne O Nolan
- Department of Psychology and Neuroscience Baylor University Waco Texas U.S.A
| | - Matthew Binder
- Department of Psychology and Neuroscience Baylor University Waco Texas U.S.A
| | - James T Okoh
- Department of Psychology and Neuroscience Baylor University Waco Texas U.S.A
| | - Kaylin Ackerman
- Department of Psychology and Neuroscience Baylor University Waco Texas U.S.A
| | - Lindsey A Tomac
- Department of Psychology and Neuroscience Baylor University Waco Texas U.S.A
| | - Joaquin N Lugo
- Institute of Biomedical Studies Baylor University Waco Texas U.S.A.,Department of Psychology and Neuroscience Baylor University Waco Texas U.S.A
| |
Collapse
|
16
|
Atherton KE, Filippini N, Zeman AZJ, Nobre AC, Butler CR. Encoding-related brain activity and accelerated forgetting in transient epileptic amnesia. Cortex 2018; 110:127-140. [PMID: 29861041 PMCID: PMC6335262 DOI: 10.1016/j.cortex.2018.04.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 04/06/2018] [Accepted: 04/30/2018] [Indexed: 12/25/2022]
Abstract
The accelerated forgetting of newly learned information is common amongst patients with epilepsy and, in particular, in the syndrome of transient epileptic amnesia (TEA). However, the neural mechanisms underlying accelerated forgetting are poorly understood. It has been hypothesised that interictal epileptiform activity during longer retention intervals disrupts normally established memory traces. Here, we tested a distinct hypothesis-that accelerated forgetting relates to the abnormal encoding of memories. We studied a group of 15 patients with TEA together with matched, healthy control subjects. Despite normal performance on standard anterograde memory tasks, patients showed accelerated forgetting of a word list over one week. We used a subsequent memory paradigm to compare encoding-related brain activity in patients and controls. Participants studied a series of visually presented scenes whilst undergoing functional MRI scanning. Recognition memory for these scenes was then probed outside the scanner after delays of 45 min and of 4 days. Patients showed poorer memory for the scenes compared with controls. In the patients but not the controls, subsequently forgotten stimuli were associated with reduced hippocampal activation at encoding. Furthermore, patients demonstrated reduced deactivation of posteromedial cortex regions upon viewing subsequently remembered stimuli as compared to subsequently forgotten ones. These data suggest that abnormal encoding-related activity in key memory areas of the brain contributes to accelerated forgetting in TEA. We propose that abnormally encoded memory traces may be particularly vulnerable to interference from subsequently encountered material and hence be forgotten more rapidly. Our results shed light on the mechanisms underlying memory impairment in epilepsy, and offer support to the proposal that accelerated forgetting may be a useful marker of subtle dysfunction in memory-related brain systems.
Collapse
Affiliation(s)
- Kathryn E Atherton
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK; Department of Experimental Psychology and Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford, UK
| | - Nicola Filippini
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Adam Z J Zeman
- Cognitive & Behavioural Neurology, University of Exeter Medical School, Exeter, UK
| | - Anna C Nobre
- Department of Experimental Psychology and Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford, UK
| | - Christopher R Butler
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK.
| |
Collapse
|
17
|
Tramoni-Negre E, Lambert I, Bartolomei F, Felician O. Long-term memory deficits in temporal lobe epilepsy. Rev Neurol (Paris) 2017; 173:490-497. [DOI: 10.1016/j.neurol.2017.06.011] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2017] [Accepted: 06/15/2017] [Indexed: 11/25/2022]
|
18
|
Burkholder DB, Jones AL, Jones DT, Fabris RR, Britton JW, Lagerlund TD, So EL, Cascino GD, Worrell GA, Shin C, St Louis EK. Frequent sleep-related bitemporal focal seizures in transient epileptic amnesia syndrome: Evidence from ictal video-EEG. Epilepsia Open 2017; 2:255-259. [PMID: 29588954 PMCID: PMC5719851 DOI: 10.1002/epi4.12040] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/03/2017] [Indexed: 11/07/2022] Open
Abstract
Two patients who shared similar presenting clinical features of anterograde and retrograde autobiographical amnesia typical of transient epileptic amnesia (TEA) underwent prolonged video electroencephalogram (VEEG) monitoring and were found to have sleep-activated epileptiform activity and frequent subclinical bitemporal seizures predominantly during sleep. Case 1 is a 59-year-old woman whose presenting complaint was memory impairment. Over 18 months, she had three distinct 8-h-long episodes of confusion and disorientation with persistent anterograde and retrograde autobiographical amnesia. VEEG recorded frequent interictal bitemporal sharp waves confined to sleep, and 14 subclinical seizures, also mostly during sleep. Case 2 is a 50-year-old woman with known focal epilepsy also presented with memory complaints. Over the course of 1 year, she had two discrete 2-h-long episodes of amnesia, with ongoing anterograde and retrograde autobiographical amnesia. VEEG recorded independent bitemporal sharp waves, and 14 subclinical seizures during sleep and drowsiness. Memory impairment improved in both patients with successful treatment of their seizures. Although the etiology of accelerated long-term forgetting (ALF) and remote memory impairment (RMI) in transient epileptic amnesia (TEA) is unknown, these cases suggest frequent sleep-related seizures may contribute, and they highlight the importance of video-EEG monitoring.
Collapse
Affiliation(s)
- David B Burkholder
- Mayo Clinic Comprehensive Epilepsy Program Mayo Clinic College of Medicine Rochester Minnesota U.S.A.,Department of Neurology Mayo Clinic College of Medicine Rochester Minnesota U.S.A
| | - Amy L Jones
- Mayo Clinic Comprehensive Epilepsy Program Mayo Clinic College of Medicine Rochester Minnesota U.S.A.,Department of Neurology Mayo Clinic College of Medicine Rochester Minnesota U.S.A
| | - David T Jones
- Department of Neurology Mayo Clinic College of Medicine Rochester Minnesota U.S.A
| | - Rachel R Fabris
- Mayo Clinic Comprehensive Epilepsy Program Mayo Clinic College of Medicine Rochester Minnesota U.S.A.,Department of Neurology Mayo Clinic College of Medicine Rochester Minnesota U.S.A.,Spectrum Health Medical Group Rockford Michigan U.S.A
| | - Jeffrey W Britton
- Mayo Clinic Comprehensive Epilepsy Program Mayo Clinic College of Medicine Rochester Minnesota U.S.A.,Department of Neurology Mayo Clinic College of Medicine Rochester Minnesota U.S.A
| | - Terrence D Lagerlund
- Mayo Clinic Comprehensive Epilepsy Program Mayo Clinic College of Medicine Rochester Minnesota U.S.A.,Department of Neurology Mayo Clinic College of Medicine Rochester Minnesota U.S.A
| | - Elson L So
- Mayo Clinic Comprehensive Epilepsy Program Mayo Clinic College of Medicine Rochester Minnesota U.S.A.,Department of Neurology Mayo Clinic College of Medicine Rochester Minnesota U.S.A
| | - Gregory D Cascino
- Mayo Clinic Comprehensive Epilepsy Program Mayo Clinic College of Medicine Rochester Minnesota U.S.A.,Department of Neurology Mayo Clinic College of Medicine Rochester Minnesota U.S.A
| | - Gregory A Worrell
- Mayo Clinic Comprehensive Epilepsy Program Mayo Clinic College of Medicine Rochester Minnesota U.S.A.,Department of Neurology Mayo Clinic College of Medicine Rochester Minnesota U.S.A
| | - Cheolsu Shin
- Mayo Clinic Comprehensive Epilepsy Program Mayo Clinic College of Medicine Rochester Minnesota U.S.A.,Department of Neurology Mayo Clinic College of Medicine Rochester Minnesota U.S.A
| | - Erik K St Louis
- Department of Neurology Mayo Clinic College of Medicine Rochester Minnesota U.S.A.,Mayo Center for Sleep Medicine Mayo Clinic College of Medicine Rochester Minnesota U.S.A.,Department of Medicine Mayo Clinic College of Medicine Rochester Minnesota U.S.A
| |
Collapse
|
19
|
Savage SA, Butler CR, Milton F, Han Y, Zeman AZ. On the nose: Olfactory disturbances in patients with transient epileptic amnesia. Epilepsy Behav 2017; 66:113-119. [PMID: 28038387 PMCID: PMC6197428 DOI: 10.1016/j.yebeh.2016.09.043] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 09/29/2016] [Accepted: 09/30/2016] [Indexed: 11/17/2022]
Abstract
OBJECTIVE While olfactory hallucinations are relatively rare in epilepsy, a high prevalence (up to 42%) has been reported in one form - Transient Epileptic Amnesia (TEA). TEA is characterized by recurring amnestic seizures and is commonly associated with persistent interictal memory deficits. Despite reports of changes in smell, olfactory ability has not been objectively assessed in this group. The aim of this study was to measure olfactory ability in patients with TEA and explore whether olfactory symptoms relate to other clinical variables. METHODS Fifty-five participants with TEA were recruited from The Impairment of Memory in Epilepsy project database. The presence of olfactory symptoms was obtained via case notes and clinical interview. Participants completed questionnaires to evaluate their olfaction and memory function subjectively. Olfactory ability was measured using the University of Pennsylvania Smell Identification Test (UPSIT). TEA participants' performance was compared to 50 matched healthy control participants. A subset of TEA participants (n=26) also completed a battery of memory tests including standard neuropsychological measures, and assessment of accelerated long-term forgetting and autobiographical memory. RESULTS Olfactory hallucinations were reported in 55% of patients with TEA. A significant reduction in smell identification (UPSIT) was found between patients with TEA and healthy controls (p<0.001). Epilepsy variables, including history of olfactory hallucinations, were not predictive of olfactory ability. Patients reported ongoing memory difficulties and performed below normative values on objective tests. While no correlation was found between objective measures of memory and olfactory performance, subjective complaints of route finding difficulty was associated with UPSIT score. CONCLUSIONS Impairments in odor identification are common in patients with TEA and exceed changes that occur in normal aging. Olfactory hallucinations occurs in approximately half of patients with TEA, but do not always coincide with reduced sense of smell. Olfactory impairment and interictal memory problems both occur frequently in TEA but are not closely associated.
Collapse
Affiliation(s)
- Sharon A. Savage
- Cognitive & Behavioural Neurology, University of Exeter Medical School, College House, St Luke’s Campus, Exeter, EX1 2LU, UK,corresponding author:
| | - Christopher R. Butler
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, John Radcliffe Hospital, OX3 9DU, UK
| | - Fraser Milton
- Discipline of Psychology, University of Exeter, Washington Singer Laboratories, Exeter, EX4 4QG, UK
| | - Yang Han
- Health Statistics, University of Exeter Medical School, South Cloisters, St Luke’s Campus, Exeter, EX1 2LU, UK
| | - Adam Z. Zeman
- Cognitive & Behavioural Neurology, University of Exeter Medical School, College House, St Luke’s Campus, Exeter, EX1 2LU, UK
| |
Collapse
|
20
|
Abstract
Transient epileptic amnesia (TEA) is a sub-type of mesial temporal lobe epilepsy, with amnesic seizures. TEA is characterized by recurrent episodes of amnesia. Diagnostic criteria are available for TEA, and these memory disturbances should not be misdiagnosed with transient global amnesia. The neuropsychological evaluation is normal, however, autobiographical memory impairment is present in 70% of the cases and accelerated long term forgetting in 44%. When a patient complains of memory disturbances, especially autobiographical memory, TEA must be considered especially if there was an amnesic episode and symptoms that suggest temporal epilepsia. Video electroencephalography monitoring of sleep is a precious diagnostic tool, as epileptiform activities are found during sleep in 83% cases. TEA is pharmaco-sensitive, with full treatment response in 73 to 96% of the cases.
Collapse
|
21
|
Barbeito-Andrés J, Bernal V, Gonzalez PN. Morphological asymmetries of mouse brain assessed by geometric morphometric analysis of MRI data. Magn Reson Imaging 2016; 34:980-9. [DOI: 10.1016/j.mri.2016.04.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 04/17/2016] [Indexed: 01/13/2023]
|
22
|
Zeman A, Hoefeijzers S, Milton F, Dewar M, Carr M, Streatfield C. The GABAB receptor agonist, baclofen, contributes to three distinct varieties of amnesia in the human brain – A detailed case report. Cortex 2016; 74:9-19. [DOI: 10.1016/j.cortex.2015.10.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2015] [Revised: 09/13/2015] [Accepted: 10/08/2015] [Indexed: 02/06/2023]
|
23
|
Korczyn AD, Schachter SC, Amlerova J, Bialer M, van Emde Boas W, Brázdil M, Brodtkorb E, Engel J, Gotman J, Komárek V, Leppik IE, Marusic P, Meletti S, Metternich B, Moulin CJA, Muhlert N, Mula M, Nakken KO, Picard F, Schulze-Bonhage A, Theodore W, Wolf P, Zeman A, Rektor I. Third International Congress on Epilepsy, Brain and Mind: Part 1. Epilepsy Behav 2015; 50:116-37. [PMID: 26276417 PMCID: PMC5256665 DOI: 10.1016/j.yebeh.2015.06.044] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 06/24/2015] [Indexed: 12/12/2022]
Abstract
Epilepsy is both a disease of the brain and the mind. Here, we present the first of two papers with extended summaries of selected presentations of the Third International Congress on Epilepsy, Brain and Mind (April 3-5, 2014; Brno, Czech Republic). Epilepsy in history and the arts and its relationships with religion were discussed, as were overviews of epilepsy and relevant aspects of social cognition, handedness, accelerated forgetting and autobiographical amnesia, and large-scale brain networks.
Collapse
Affiliation(s)
- Amos D Korczyn
- Sackler School of Medicine, Tel Aviv University, Ramat Aviv, Israel
| | - Steven C Schachter
- Consortia for Improving Medicine with Innovation and Technology, Harvard Medical School, Boston, MA, USA.
| | - Jana Amlerova
- Department of Neurology, Charles University, 2nd Faculty of Medicine, Motol University Hospital, Prague, Czech Republic
| | - Meir Bialer
- Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Walter van Emde Boas
- Department of EEG, Dutch Epilepsy Clinics Foundation (SEIN), Heemstede, The Netherlands; Epilepsy Monitoring Unit, Dutch Epilepsy Clinics Foundation (SEIN), Heemstede, The Netherlands
| | - Milan Brázdil
- Masaryk University, Brno Epilepsy Center, St. Anne's Hospital and School of Medicine, Brno, Czech Republic; Central European Institute of Technology (CEITEC), Brno, Czech Republic
| | - Eylert Brodtkorb
- Department of Neurology and Clinical Neurophysiology, St. Olav's Hospital, Trondheim University Hospital, Trondheim, Norway; Department of Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway
| | | | - Jean Gotman
- Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Vladmir Komárek
- Department of Paediatric Neurology, Charles University, 2nd Faculty of Medicine, Motol University Hospital, Prague, Czech Republic
| | - Ilo E Leppik
- MINCEP Epilepsy Care, University of Minnesota, Minneapolis, MN, USA; College of Pharmacy, University of Minnesota, Minneapolis, MN, USA
| | - Petr Marusic
- Department of Neurology, Charles University, 2nd Faculty of Medicine, Motol University Hospital, Prague, Czech Republic
| | - Stefano Meletti
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | | | - Chris J A Moulin
- Laboratory for the Study of Learning and Development, University of Bourgogne, Dijon, France
| | - Nils Muhlert
- School of Psychology and Cardiff University Brain Research Imaging Centre, Cardiff University, Cardiff, Wales, UK
| | - Marco Mula
- Epilepsy Group, Atkinson Morley Regional Neuroscience Centre, St. George's Hospital, London, UK; Institute of Medical and Biomedical Sciences, St. George's University of London, London, UK
| | - Karl O Nakken
- National Centre for Epilepsy, Oslo University Hospital, Norway
| | - Fabienne Picard
- Department of Neurology, University Hospital and Medical School of Geneva, Switzerland
| | | | - William Theodore
- Clinical Epilepsy Section, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - Peter Wolf
- Danish Epilepsy Centre Filadelfia, Dianalund, Denmark; Department of Clinical Medicine, Neurological Service, Federal University of Santa Catarina, Florianópolis, SC, Brazil
| | - Adam Zeman
- University of Exeter Medical School, St. Luke's Campus, Exeter, UK
| | - Ivan Rektor
- Masaryk University, Brno Epilepsy Center, St. Anne's Hospital and School of Medicine, Brno, Czech Republic; Central European Institute of Technology (CEITEC), Brno, Czech Republic
| |
Collapse
|
24
|
Huijgen J, Samson S. The hippocampus: A central node in a large-scale brain network for memory. Rev Neurol (Paris) 2015; 171:204-16. [DOI: 10.1016/j.neurol.2015.01.557] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 01/22/2015] [Accepted: 01/29/2015] [Indexed: 11/25/2022]
|
25
|
Klasson N, Olsson E, Rudemo M, Eckerström C, Malmgren H, Wallin A. Valid and efficient manual estimates of intracranial volume from magnetic resonance images. BMC Med Imaging 2015; 15:5. [PMID: 25879816 PMCID: PMC4344732 DOI: 10.1186/s12880-015-0045-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 01/30/2015] [Indexed: 12/29/2022] Open
Abstract
Background Manual segmentations of the whole intracranial vault in high-resolution magnetic resonance images are often regarded as very time-consuming. Therefore it is common to only segment a few linearly spaced intracranial areas to estimate the whole volume. The purpose of the present study was to evaluate how the validity of intracranial volume estimates is affected by the chosen interpolation method, orientation of the intracranial areas and the linear spacing between them. Methods Intracranial volumes were manually segmented on 62 participants from the Gothenburg MCI study using 1.5 T, T1-weighted magnetic resonance images. Estimates of the intracranial volumes were then derived using subsamples of linearly spaced coronal, sagittal or transversal intracranial areas from the same volumes. The subsamples of intracranial areas were interpolated into volume estimates by three different interpolation methods. The linear spacing between the intracranial areas ranged from 2 to 50 mm and the validity of the estimates was determined by comparison with the entire intracranial volumes. Results A progressive decrease in intra-class correlation and an increase in percentage error could be seen with increased linear spacing between intracranial areas. With small linear spacing (≤15 mm), orientation of the intracranial areas and interpolation method had negligible effects on the validity. With larger linear spacing, the best validity was achieved using cubic spline interpolation with either coronal or sagittal intracranial areas. Even at a linear spacing of 50 mm, cubic spline interpolation on either coronal or sagittal intracranial areas had a mean absolute agreement intra-class correlation with the entire intracranial volumes above 0.97. Conclusion Cubic spline interpolation in combination with linearly spaced sagittal or coronal intracranial areas overall resulted in the most valid and robust estimates of intracranial volume. Using this method, valid ICV estimates could be obtained in less than five minutes per patient.
Collapse
Affiliation(s)
- Niklas Klasson
- Institute of Psychiatry and Neurochemistry, Department of Neuroscience and physiology, The Sahlgrenska Academy, University of Gothenburg, Box 430, SE-405 30, Göteborg, Sweden.
| | - Erik Olsson
- Institute of Psychiatry and Neurochemistry, Department of Neuroscience and physiology, The Sahlgrenska Academy, University of Gothenburg, Box 430, SE-405 30, Göteborg, Sweden.
| | - Mats Rudemo
- Department of Mathematical Sciences, Chalmers University of Technology and University of Gothenburg, SE-412 96, Göteborg, Sweden.
| | - Carl Eckerström
- Institute of Psychiatry and Neurochemistry, Department of Neuroscience and physiology, The Sahlgrenska Academy, University of Gothenburg, Box 430, SE-405 30, Göteborg, Sweden.
| | - Helge Malmgren
- Institute of Psychiatry and Neurochemistry, Department of Neuroscience and physiology, The Sahlgrenska Academy, University of Gothenburg, Box 430, SE-405 30, Göteborg, Sweden. .,Department of Philosophy, Linguistics and Theory of Science, University of Gothenburg, Box 200, SE-405 30, Göteborg, Sweden.
| | - Anders Wallin
- Institute of Psychiatry and Neurochemistry, Department of Neuroscience and physiology, The Sahlgrenska Academy, University of Gothenburg, Box 430, SE-405 30, Göteborg, Sweden.
| |
Collapse
|
26
|
Dewar M, Hoefeijzers S, Zeman A, Butler C, Della Sala S. Impaired picture recognition in transient epileptic amnesia. Epilepsy Behav 2015; 42:107-16. [PMID: 25506793 DOI: 10.1016/j.yebeh.2014.10.032] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 10/06/2014] [Accepted: 10/28/2014] [Indexed: 11/29/2022]
Abstract
Transient epileptic amnesia (TEA) is an epileptic syndrome characterized by recurrent, brief episodes of amnesia. Transient epileptic amnesia is often associated with the rapid decline in recall of new information over hours to days (accelerated long-term forgetting - 'ALF'). It remains unknown how recognition memory is affected in TEA over time. Here, we report a systematic study of picture recognition in patients with TEA over the course of one week. Sixteen patients with TEA and 16 matched controls were presented with 300 photos of everyday life scenes. Yes/no picture recognition was tested 5min, 2.5h, 7.5h, 24h, and 1week after picture presentation using a subset of target pictures as well as similar and different foils. Picture recognition was impaired in the patient group at all test times, including the 5-minute test, but it declined normally over the course of 1week. This impairment was associated predominantly with an increased false alarm rate, especially for similar foils. High performance on a control test indicates that this impairment was not associated with perceptual or discrimination deficits. Our findings suggest that, at least in some TEA patients with ALF in verbal recall, picture recognition does not decline more rapidly than in controls over 1week. However, our findings of an early picture recognition deficit suggest that new visual memories are impoverished after minutes in TEA. This could be the result of deficient encoding or impaired early consolidation. The early picture recognition deficit observed could reflect either the early stages of the process that leads to ALF or a separable deficit of anterograde memory in TEA. Lastly, our study suggests that at least some patients with TEA are prone to falsely recognizing new everyday visual information that they have not in fact seen previously. This deficit, alongside their ALF in free recall, likely affects everyday memory performance.
Collapse
Affiliation(s)
- Michaela Dewar
- Human Cognitive Neuroscience, Psychology, University of Edinburgh, Edinburgh, UK; Psychology, School of Life Sciences, Heriot-Watt University, Edinburgh, UK.
| | - Serge Hoefeijzers
- Human Cognitive Neuroscience, Psychology, University of Edinburgh, Edinburgh, UK
| | - Adam Zeman
- Cognitive and Behavioural Neurology, University of Exeter Medical School, Exeter, UK
| | - Christopher Butler
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Sergio Della Sala
- Human Cognitive Neuroscience, Psychology, University of Edinburgh, Edinburgh, UK; Centre for Cognitive Ageing and Cognitive Epidemiology, Psychology, University of Edinburgh, Edinburgh, UK
| |
Collapse
|
27
|
Abstract
Although Alzheimer's disease (AD) is a common cause of memory impairment and dementia in the elderly disturbed memory function is a widespread subjective and/or objective symptom in a variety of medical conditions. The early detection and correct distinction of AD from non-AD memory impairment is critically important to detect possibly treatable and reversible underlying causes. In the context of clinical research, it is crucial to correctly distinguish between AD or non-AD memory impairment in order to build homogenous study populations for the assessment of new therapeutic possibilities. The distinction of AD from non-AD memory impairment may be difficult, especially in mildly affected patients, due to an overlap of clinical symptoms and biomarker alterations between AD and certain non-AD conditions. This review aims to describe recent aspects of the differential diagnosis of AD and non-AD related memory impairment and how these may be considered in the presence of memory deficits.
Collapse
Affiliation(s)
- Sönke Arlt
- Department of Psychiatry and Psychotherapy, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| |
Collapse
|
28
|
Cretin B, Philippi N, Sellal F, Dibitonto L, Martin-Hunyadi C, Blanc F. Can the syndrome of transient epileptic amnesia be the first feature of Alzheimer's disease? Seizure 2014; 23:918-20. [PMID: 25123897 DOI: 10.1016/j.seizure.2014.07.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 07/03/2014] [Accepted: 07/10/2014] [Indexed: 10/25/2022] Open
Affiliation(s)
- Benjamin Cretin
- Unité de Neuropsychologie, Service de Neurologie des Hôpitaux Universitaires de Strasbourg, Strasbourg, France; Centre Mémoire, de Ressources et de Recherche d'Alsace (Strasbourg-Colmar), France; Laboratoire ICube, CNRS-Université de Strasbourg, France; Centre de Compétences des démences rares des Hôpitaux Universitaires de Strasbourg, France.
| | - Nathalie Philippi
- Unité de Neuropsychologie, Service de Neurologie des Hôpitaux Universitaires de Strasbourg, Strasbourg, France; Centre Mémoire, de Ressources et de Recherche d'Alsace (Strasbourg-Colmar), France; Laboratoire ICube, CNRS-Université de Strasbourg, France; Centre de Compétences des démences rares des Hôpitaux Universitaires de Strasbourg, France
| | - François Sellal
- Centre Mémoire, de Ressources et de Recherche d'Alsace (Strasbourg-Colmar), France; Service de Neurologie, Hospices Civils de Colmar, France
| | - Laure Dibitonto
- Unité de Neuropsychologie, Service de Neurologie des Hôpitaux Universitaires de Strasbourg, Strasbourg, France; Centre Mémoire, de Ressources et de Recherche d'Alsace (Strasbourg-Colmar), France; Laboratoire ICube, CNRS-Université de Strasbourg, France; Centre de Compétences des démences rares des Hôpitaux Universitaires de Strasbourg, France
| | | | - Frederic Blanc
- Unité de Neuropsychologie, Service de Neurologie des Hôpitaux Universitaires de Strasbourg, Strasbourg, France; Centre Mémoire, de Ressources et de Recherche d'Alsace (Strasbourg-Colmar), France; Laboratoire ICube, CNRS-Université de Strasbourg, France; Centre de Compétences des démences rares des Hôpitaux Universitaires de Strasbourg, France
| |
Collapse
|
29
|
Automatic segmentation of brain MRI through stationary wavelet transform and random forests. Pattern Anal Appl 2014. [DOI: 10.1007/s10044-014-0373-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
30
|
Nicastro N, Picard F, Assal F. Transient global amnesia mimics: Transient epileptic amnesia. EPILEPSY & BEHAVIOR CASE REPORTS 2014; 2:100-1. [PMID: 25667881 PMCID: PMC4308042 DOI: 10.1016/j.ebcr.2014.03.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 03/25/2014] [Indexed: 11/06/2022]
Abstract
We describe the case of a 79-year-old patient referred for suspected transient global amnesia, after an episode of anterograde amnesia which lasted 90 min. An EEG, performed after the episode, showed bilateral temporal electrographic seizures, orienting the diagnosis toward a transient epileptic amnesia. Transient epileptic amnesia is defined by temporal lobe epilepsy characterized by recurrent transient amnestic episodes of 30–90 min in duration, sometimes associated with olfactory hallucinations or oral automatisms. Response to antiepileptic drugs is excellent. We would like to raise awareness toward this epileptic amnesia when facing atypical or recurrent transient amnestic episodes.
Collapse
Affiliation(s)
- Nicolas Nicastro
- Department of Neurology, Geneva University Hospital, Switzerland
| | - Fabienne Picard
- Department of Neurology, Geneva University Hospital, Switzerland
| | - Frederic Assal
- Department of Neurology, Geneva University Hospital, Switzerland
| |
Collapse
|
31
|
Atherton KE, Nobre AC, Zeman AZ, Butler CR. Sleep-dependent memory consolidation and accelerated forgetting. Cortex 2014; 54:92-105. [PMID: 24657478 PMCID: PMC4007033 DOI: 10.1016/j.cortex.2014.02.009] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 01/28/2014] [Accepted: 02/10/2014] [Indexed: 11/26/2022]
Abstract
Accelerated long-term forgetting (ALF) is a form of memory impairment in which learning and initial retention of information appear normal but subsequent forgetting is excessively rapid. ALF is most commonly associated with epilepsy and, in particular, a form of late-onset epilepsy called transient epileptic amnesia (TEA). ALF provides a novel opportunity to investigate post-encoding memory processes, such as consolidation. Sleep is implicated in the consolidation of memory in healthy people and a deficit in sleep-dependent memory consolidation has been proposed as an explanation for ALF. If this proposal were correct, then sleep would not benefit memory retention in people with ALF as much as in healthy people, and ALF might only be apparent when the retention interval contains sleep. To test this theory, we compared performance on a sleep-sensitive memory task over a night of sleep and a day of wakefulness. We found, contrary to the hypothesis, that sleep benefits memory retention in TEA patients with ALF and that this benefit is no smaller in magnitude than that seen in healthy controls. Indeed, the patients performed significantly more poorly than the controls only in the wake condition and not the sleep condition. Patients were matched to controls on learning rate, initial retention, and the effect of time of day on cognitive performance. These results indicate that ALF is not caused by a disruption of sleep-dependent memory consolidation. Instead, ALF may be due to an encoding abnormality that goes undetected on behavioural assessments of learning, or by a deficit in memory consolidation processes that are not sleep-dependent.
Collapse
Affiliation(s)
- Kathryn E Atherton
- Department of Experimental Psychology, University of Oxford, Oxford, UK; Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
| | - Anna C Nobre
- Department of Experimental Psychology, University of Oxford, Oxford, UK; Oxford Centre for Human Brain Activity, University of Oxford, Oxford, UK
| | - Adam Z Zeman
- Cognitive and Behavioural Neurology Research Group, University of Exeter Medical School, UK
| | | |
Collapse
|
32
|
Elliott G, Isaac CL, Muhlert N. Measuring forgetting: a critical review of accelerated long-term forgetting studies. Cortex 2014; 54:16-32. [PMID: 24631847 PMCID: PMC4007031 DOI: 10.1016/j.cortex.2014.02.001] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 12/09/2013] [Accepted: 02/03/2014] [Indexed: 12/31/2022]
Abstract
Accelerated long-term forgetting (ALF) refers to abnormal forgetting over hours to weeks despite normal acquisition or initial consolidation. Since standardised assessments of memory typically only test at delays of up to 40-minutes, ALF may go undetected in clinical practice. The memory difficulties associated with ALF can however cause considerable distress to patients. It is important therefore that clinicians are aware that ALF may represent a distinct phenomenon that will require additional and careful assessment to aid patients' understanding of the condition and assist in developing strategies to address its effects. At the same time, ALF may also provide insight into long-term memory processes. Studies of ALF in patients with epilepsy have so far demonstrated mixed results, which may reflect differences in methodology. This review explores the methodological issues that can affect forgetting, such as the effects of age, general cognitive function, test sensitivity and initial learning. It then evaluates the extent to which existing studies have considered these key issues. We outline the points to consider when designing ALF studies that can be used to help improve their validity. These issues can also help to explain some of the mixed findings in studies of ALF and inform the design of standardised tests for assessing ALF in clinical practice.
Collapse
Affiliation(s)
- Gemma Elliott
- Clinical Neuropsychology Services, Royal Hallamshire Hospital, Sheffield, UK; Department of Psychology, University of Sheffield, Sheffield, UK
| | - Claire L Isaac
- Clinical Neuropsychology Services, Royal Hallamshire Hospital, Sheffield, UK; Neuropsychology Department, Lincolnshire Partnership NHS Foundation Trust, Lincoln, UK
| | - Nils Muhlert
- Neuropsychology Department, Lincolnshire Partnership NHS Foundation Trust, Lincoln, UK; Cognitive Neuroscience, School of Psychology, Cardiff University, Cardiff, UK.
| |
Collapse
|
33
|
Asadi-Pooya AA. Transient epileptic amnesia: a concise review. Epilepsy Behav 2014; 31:243-5. [PMID: 24230990 DOI: 10.1016/j.yebeh.2013.10.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 10/13/2013] [Accepted: 10/14/2013] [Indexed: 12/15/2022]
Abstract
Transient epileptic amnesia (TEA) is a distinctive syndrome and comprises episodic transient amnesia with an epileptic basis, without impairment of other aspects of cognitive function. Additional interictal memory deficits are common in TEA. An epileptic origin, after other etiologies have been excluded, should be considered and carefully investigated in patients complaining of isolated memory disturbances, particularly with recurrent short-lasting amnesic attacks. In all suspected cases of epilepsy, a detailed clinical history is of paramount importance, but ancillary tests including EEG and MRI could be very helpful. Transient epileptic amnesia is typically a benign and treatable condition. Future studies should investigate the exact mechanism(s) of this unique syndrome.
Collapse
Affiliation(s)
- Ali A Asadi-Pooya
- Neurosciences Research Center, Shiraz Medical School, Shiraz University of Medical Sciences, Shiraz, Iran; Jefferson Comprehensive Epilepsy Center, Department of Neurology, Thomas Jefferson University, Philadelphia, USA.
| |
Collapse
|
34
|
Can temporal lobe epilepsy surgery ameliorate accelerated long-term forgetting? Neuropsychologia 2014; 53:64-74. [DOI: 10.1016/j.neuropsychologia.2013.11.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2013] [Revised: 10/29/2013] [Accepted: 11/12/2013] [Indexed: 11/22/2022]
|