John S Duncan

UCL Eastman Dental Institute, Londinium, England, United Kingdom

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Publications (584)3343.02 Total impact

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    ABSTRACT: To define factors that predict whether patients with pharmacoresistant focal epilepsy are offered epilepsy surgery (including invasive EEG) and the main reasons for not proceeding with these after non-invasive presurgical evaluation. We retrospectively analysed data from 612 consecutive patients with focal epilepsy admitted to a video-EEG Telemetry Unit for presurgical evaluation, and used a multivariate logistic regression model to assess the predictive value of factors for being offered potentially curative surgery. In the multivariate analysis, bilateral lesions on MRI (OR: 0.10; 95% CI 0.03 to 0.24), no lesion (OR: 0.33; 95% CI 0.22 to 0.49) or extratemporal lobe epilepsy (OR: 0.30; 95% CI 0.20 to 0.45) were the only factors that significantly reduced the probability of being offered surgery. 32% of patients who were offered epilepsy surgery decided against proceeding. There was a low chance (<10%) of being offered surgery if there were bilateral lesions on MRI and extratemporal lobe epilepsy. Patients should be given advice on the risk/benefit ratio and of realistic outcomes of epilepsy surgery; this may help reduce the number of patients who refuse surgery after comprehensive workup. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
    Journal of neurology, neurosurgery, and psychiatry 05/2015; DOI:10.1136/jnnp-2014-310148 · 5.58 Impact Factor
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    ABSTRACT: In the human brain, a default mode or task-negative network shows reduced activity during many cognitive tasks, and is often associated with internally-directed processes such as mind wandering and thoughts about the self. In contrast to this task-negative pattern, we show increased activity during a large and demanding switch in task set. Furthermore, we employ multi-voxel pattern analysis and find that regions of interest within default mode network are encoding task-relevant information during task performance. Activity in this network may be driven by major revisions of cognitive context, whether internally or externally focused.
    eLife Sciences 04/2015; 4. DOI:10.7554/eLife.06481 · 8.52 Impact Factor
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    ABSTRACT: Brain vessels are among the most critical landmarks that need to be assessed for mitigating surgical risks in stereo-electroencephalography (SEEG) implantation. Intracranial haemorrhage is the most common complication associated with implantation, carrying significantly associated morbidity. SEEG planning is done pre-operatively to identify avascular trajectories for the electrodes. In current practice, neurosurgeons have no assistance in the planning of electrode trajectories. There is great interest in developing computer-assisted planning systems that can optimise the safety profile of electrode trajectories, maximising the distance to critical structures. This paper presents a method that integrates the concepts of scale, neighbourhood structure and feature stability with the aim of improving robustness and accuracy of vessel extraction within a SEEG planning system. The developed method accounts for scale and vicinity of a voxel by formulating the problem within a multi-scale tensor voting framework. Feature stability is achieved through a similarity measure that evaluates the multi-modal consistency in vesselness responses. The proposed measurement allows the combination of multiple images modalities into a single image that is used within the planning system to visualise critical vessels. Twelve paired data sets from two image modalities available within the planning system were used for evaluation. The mean Dice similarity coefficient was [Formula: see text], representing a statistically significantly improvement when compared to a semi-automated single human rater, single-modality segmentation protocol used in clinical practice ([Formula: see text]). Multi-modal vessel extraction is superior to semi-automated single-modality segmentation, indicating the possibility of safer SEEG planning, with reduced patient morbidity.
    International Journal of Computer Assisted Radiology and Surgery 04/2015; DOI:10.1007/s11548-015-1174-5 · 1.66 Impact Factor
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    ABSTRACT: To examine the cognitive risks of temporal lobe surgery in patients aged 50 years and older.
    Seizure 03/2015; 29. DOI:10.1016/j.seizure.2015.03.017 · 2.06 Impact Factor
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    ABSTRACT: Qualitatively, FLAIR MR imaging is sensitive to the detection of hippocampal sclerosis (HS). Quantitative analysis of T2 maps provides a useful objective measure and increased sensitivity over visual inspection of T2-weighted scans. We aimed to determine whether quantification of normalised FLAIR is as sensitive as T2 mapping in detection of HS. Dual echo T2 and FLAIR MR images were retrospectively analysed in 27 patients with histologically confirmed HS and increased T2 signal in ipsilateral hippocampus and 14 healthy controls. Regions of interest were manually segmented in all hippocampi aiming to avoid inclusion of CSF. Hippocampal T2 values and measures of normalised FLAIR Signal Intensity (nFSI) were compared in healthy and sclerotic hippocampi. HS was identified on T2 values with 100% sensitivity and 100% specificity. HS was identified on nFSI measures with 60% sensitivity and 93% specificity. T2 mapping is superior to nFSI for identification of HS.
    03/2015; 28. DOI:10.1016/j.nicl.2015.03.004
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    ABSTRACT: To develop a clinically applicable memory functional MRI (fMRI) method of predicting postsurgical memory outcome in individual patients. In this prospective cohort study, 50 patients with temporal lobe epilepsy (23 left) and 26 controls underwent an fMRI memory encoding paradigm of words with a subsequent out-of-scanner recognition assessment. Neuropsychological assessment was performed preoperatively and 4 months after anterior temporal lobe resection, and at equal time intervals in controls. An event-related analysis was used to explore brain activations for words remembered and change in verbal memory scores 4 months after surgery was correlated with preoperative activations. Individual lateralization indices were calculated within a medial temporal and frontal region and compared with other clinical parameters (hippocampal volume, preoperative verbal memory, age at onset of epilepsy, and language lateralization) as a predictor of verbal memory outcome. In left temporal lobe epilepsy patients, left frontal and anterior medial temporal activations correlated significantly with greater verbal memory decline, while bilateral posterior hippocampal activation correlated with less verbal memory decline postoperatively. In a multivariate regression model, left lateralized memory lateralization index (≥0.5) within a medial temporal and frontal mask was the best predictor of verbal memory outcome after surgery in the dominant hemisphere in individual patients. Neither clinical nor functional MRI parameters predicted verbal memory decline after nondominant temporal lobe resection. We propose a clinically applicable memory fMRI paradigm to predict postoperative verbal memory decline after surgery in the language-dominant hemisphere in individual patients. © 2015 American Academy of Neurology.
    Neurology 03/2015; 84(15). DOI:10.1212/WNL.0000000000001461 · 8.30 Impact Factor
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    ABSTRACT: A 58-year-old woman presented to neuropsychiatric services with increased frequency of confusional episodes and intermittent psychotic symptoms. She had a 19-year history of atypical epileptic seizures and cognitive decline. Detailed review of history and clinical investigations revealed that she had accumulated sufficient features to meet diagnostic criteria for systemic lupus erythematosus (SLE). She had previously had lymphopenia and a malar rash; she had positive antinuclear, anti-Ro (anti-Sjögren's-syndrome-related antigen A) and anti-SM (anti-Smith Antibody) antibodies, and elevated erythrocyte sedimentation rate. The seizures, cognitive impairment and psychosis were attributable to neuropsychiatric SLE. Treatment with immune-modulating therapy, cyclophosphamide, resulted in significant improvement in subjective and objective clinical presentation. Neuropsychiatric SLE should be considered a potential differential diagnosis for patients presenting with seizures, psychotic symptoms or cognitive decline. A detailed clinical evaluation with review of the medical history and appropriate laboratory analyses allows this diagnosis to be made, and appropriate treatment to be initiated. 2015 BMJ Publishing Group Ltd.
    Case Reports 03/2015; 2015(mar05 1). DOI:10.1136/bcr-2014-208215
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    ABSTRACT: Objective We present a single-center prospective study, validating the use of 3D multimodality imaging (3DMMI) in patients undergoing intracranial electroencephalography (IC-EEG).MethodsIC-EEG implantation preparation entails first designing of the overall strategy of implantation (strategy) and second the precise details of implantation (planning). For each case, the multidisciplinary team made decisions on strategy and planning before the disclosure of multimodal brain imaging models. Any changes to decisions, following disclosure of the multimodal models, were recorded.ResultsDisclosure of 3DMMI led to a change in strategy in 15 (34%) of 44 individuals. The changes included addition and subtraction of electrodes, addition of grids, and going directly to resection. For the detailed surgical planning, 3DMMI led to a change in 35 (81%) of 43 individuals. Twenty-five (100%) of 25 patients undergoing stereo-EEG (SEEG) underwent a change in electrode placement, with 158 (75%) of 212 electrode trajectories being altered.SignificanceThe use of 3DMMI makes substantial changes in clinical decision making.
    Epilepsia 02/2015; 56(3). DOI:10.1111/epi.12924 · 4.58 Impact Factor
  • John S Duncan, Clement Hamani
    Neurology 01/2015; 84(8). DOI:10.1212/WNL.0000000000001297 · 8.30 Impact Factor
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    ABSTRACT: This study aimed to determine clinical features of adult patients with gelastic seizures recorded on video –electroencephalography (EEG) over a 5-year period. We screened video-EEG telemetry reports for the occurrence of the term “gelastic” seizures, and assessed the semiology, EEG features, and duration of those seizures. Gelastic seizures were identified in 19 (0.8%) of 2,446 admissions. The presumed epileptogenic zone was in the hypothalamus in one third of the cases, temporal lobe epilepsy was diagnosed in another third, and the remainder of the cases presenting with gelastic seizures were classified as frontal, parietal lobe epilepsy or remained undetermined or were multifocal. Gelastic seizures were embedded in a semiology, with part of the seizure showing features of automotor seizures. A small proportion of patients underwent epilepsy surgery. Outcome of epilepsy surgery was related to the underlying pathology; two patients with hippocampal sclerosis had good outcomes following temporal lobe resection and one of four patients with hypothalamic hamartomas undergoing gamma knife surgery had a good outcome.
    Epilepsia 12/2014; 56(1). DOI:10.1111/epi.12868 · 4.58 Impact Factor
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    ABSTRACT: In temporal lobe epilepsy (TLE) due to hippocampal sclerosis reorganisation in the memory encoding network has been consistently described. Distinct areas of reorganisation have been shown to be efficient when associated with successful subsequent memory formation or inefficient when not associated with successful subsequent memory. We investigated the effect of clinical parameters that modulate memory functions: age at onset of epilepsy, epilepsy duration and seizure frequency in a large cohort of patients.Methods We studied 53 patients with unilateral TLE and hippocampal sclerosis (29 left). All participants performed a functional magnetic resonance imaging memory encoding paradigm of faces and words. A continuous regression analysis was used to investigate the effects of age at onset of epilepsy, epilepsy duration and seizure frequency on the activation patterns in the memory encoding network.ResultsEarlier age at onset of epilepsy was associated with left posterior hippocampus activations that were involved in successful subsequent memory formation in left hippocampal sclerosis patients. No association of age at onset of epilepsy was seen with face encoding in right hippocampal sclerosis patients. In both left hippocampal sclerosis patients during word encoding and right hippocampal sclerosis patients during face encoding, shorter duration of epilepsy and lower seizure frequency were associated with medial temporal lobe activations that were involved in successful memory formation. Longer epilepsy duration and higher seizure frequency were associated with contralateral extra-temporal activations that were not associated with successful memory formation.Conclusion Age at onset of epilepsy influenced verbal memory encoding in patients with TLE due to hippocampal sclerosis in the speech-dominant hemisphere. Shorter duration of epilepsy and lower seizure frequency were associated with less disruption of the efficient memory encoding network whilst longer duration and higher seizure frequency were associated with greater, inefficient, extra-temporal reorganisation.
    Epilepsy Research 11/2014; 110. DOI:10.1016/j.eplepsyres.2014.11.001 · 2.19 Impact Factor
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    ABSTRACT: Purpose To assess the utility of retigabine (RTG) for epilepsy in clinical practice at a single UK tertiary centre. Methods We identified all individuals who were offered RTG from April 2011 to May 2013. We collected demographics, seizure types, previous and current AEDs, starting and maximum attained daily dose of RTG, clinical benefits, side effects, and reason to discontinue RTG from in- and outpatient encounters until February 28, 2014. Results 145 people who had failed a median of 11 AEDs took at least one dose of RTG. One year retention was 32% and decreased following the safety alert by the US Federal Drug Administration (FDA) in April 2013. None became seizure free. 34 people (24%) reported a benefit that was ongoing at last assessment in five (3%). The most relevant benefit was the significant reduction or cessation of drop attacks or seizure related falls in four women, this persisted at last assessment in two. The presence of simple partial seizures was associated with longer retention, as was a higher attained dose of RTG. Adverse effects were seen in 74% and largely CNS-related or nonspecific and affected the genitourinary system in 13%. Conclusion Retention of RTG was less favourable compared to data from open label extension studies of the regulatory trials. In comparison with historical data on similar retention audits retention of RTG at one year appears to be less than lamotrigine, topiramate, levetiracetam, pregabalin, zonisamide, and lacosamide, and slightly higher than gabapentin.
    Seizure 11/2014; 23(10). DOI:10.1016/j.seizure.2014.08.001 · 2.06 Impact Factor
  • Umair J. Chaudhary, John S. Duncan
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    ABSTRACT: The lifetime prevalence of epilepsy ranges from 2.7 to 12.4 per 1000 in Western countries. Around 30% of patients with epilepsy remain refractory to antiepileptic drugs and continue to have seizures. Noninvasive imaging techniques such as functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) have helped to better understand mechanisms of seizure generation and propagation, and to localize epileptic, eloquent, and cognitive networks. In this review, the clinical applications of fMRI and DTI are discussed, for mapping cognitive and epileptic networks and organization of white matter tracts in individuals with epilepsy. Copyright © 2014 Elsevier Inc. All rights reserved.
    Neuroimaging Clinics of North America 11/2014; DOI:10.1016/j.nic.2014.07.001 · 1.29 Impact Factor
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    ABSTRACT: Prefrontal neurons code many kinds of behaviourally relevant visual information. In behaving monkeys, we used a cued target detection task to address coding of objects, behavioural categories and spatial locations, examining the temporal evolution of neural activity across dorsal and ventral regions of the lateral prefrontal cortex (encompassing parts of areas 9, 46, 45A and 8A), and across the two cerebral hemispheres. Within each hemisphere there was little evidence for regional specialisation, with neurons in dorsal and ventral regions showing closely similar patterns of selectivity for objects, categories and locations. For a stimulus in either visual field, however, there was a strong and temporally specific difference in response in the two cerebral hemispheres. In the first part of the visual response (50–250 ms from stimulus onset), processing in each hemisphere was largely restricted to contralateral stimuli, with strong responses to such stimuli, and selectivity for both object and category. Later (300–500 ms), responses to ipsilateral stimuli also appeared, many cells now responding more strongly to ipsilateral than to contralateral stimuli, and many showing selectivity for category. Activity on error trials showed that late activity in both hemispheres reflected the animal's final decision. As information is processed towards a behavioural decision, its encoding spreads to encompass large, bilateral regions of prefrontal cortex.
    European Journal of Neuroscience 10/2014; 41(1). DOI:10.1111/ejn.12754 · 3.67 Impact Factor
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    ABSTRACT: Rationale: Current techniques for monitoring patients for apnoea suffer from significant limitations. These include insufficient availability to meet diagnostic needs, cost, accuracy of results in the presence of artefacts and difficulty of use in unsupervised conditions. Objectives: We created and clinically tested a novel miniature medical device that targets overcoming these limitations. Methods: We studied 20 healthy control participants and 10 patients who had been referred for sleep apnoea diagnosis. The performances of the new system and also of the Food and Drug Administration (FDA) approved SOMNO clinical system, conventionally used for sleep apnoea diagnosis were evaluated under the same conditions. Both systems were tested during a normal night of sleep in controls and patients. Their performances were quantified in terms of detection of apnoea and hypopnoea in individual 10 s epochs, which were compared with scoring of signals by a blinded clinician. Main results: For spontaneous apnoeas during natural sleep and considering the clinician scorer as the gold standard, the new wearable apnoea detection device had 88.6% sensitivity and 99.6% specificity. In comparison the SOMNO system had 14.3% sensitivity and 99.3% specificity. The novel device had been specifically designed to detect apnoea, but if apnoea and hypopnoea during sleep were both considered in the assessment, the sensitivity and specificity were 77.1% and 99.7%, respectively, versus 54% and 98.5%, respectively, for the SOMNO. Conclusions: The performance of the novel device compares very well to the scoring by an experienced clinician even in the presence of breathing artefacts, in this small pilot study. This can potentially make it a real solution for apnoea home monitoring.
    BMJ Open 10/2014; 4(10):e005299. DOI:10.1136/bmjopen-2014-005299 · 2.06 Impact Factor
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    ABSTRACT: As greater numbers of us are living longer, it is increasingly important to understand how we can age healthily. Although old age is often stereotyped as a time of declining mental abilities and inflexibility, cognitive neuroscience reveals that older adults use neural and cognitive resources flexibly, recruiting novel neural regions and cognitive processes when necessary. Our aim in this project is to understand how age-related changes to neural structure and function interact to support cognitive abilities across the lifespan. We are recruiting a population-based cohort of 3000 adults aged 18 and over into Stage 1 of the project, where they complete an interview including health and lifestyle questions, a core cognitive assessment, and a self-completed questionnaire of lifetime experiences and physical activity. Of those interviewed, 700 participants aged 18-87 (100 per age decile) continue to Stage 2 where they undergo cognitive testing and provide measures of brain structure and function. Cognition is assessed across multiple domains including attention and executive control, language, memory, emotion, action control and learning. A subset of 280 adults return for in-depth neurocognitive assessment in Stage 3, using functional neuroimaging experiments across our key cognitive domains.Formal statistical models will be used to examine the changes that occur with healthy ageing, and to evaluate age-related reorganisation in terms of cognitive and neural functions invoked to compensate for overall age-related brain structural decline. Taken together the three stages provide deep phenotyping that will allow us to measure neural activity and flexibility during performance across a number of core cognitive functions. This approach offers hypothesis-driven insights into the relationship between brain and behaviour in healthy ageing that are relevant to the general population. Our study is a unique resource of neuroimaging and cognitive measures relevant to change across the adult lifespan. Because we focus on normal age-related changes, our results may contribute to changing views about the ageing process, lead to targeted interventions, and reveal how normal ageing relates to frail ageing in clinicopathological conditions such as Alzheimer's disease.
    BMC Neurology 10/2014; 14(1):204. DOI:10.1186/s12883-014-0204-1 · 2.49 Impact Factor
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    ABSTRACT: Echo Planar Imaging (EPI) is routinely used in diffusion and functional MR imaging due to its rapid acqui-sition time. However, the long readout period makes it prone to susceptibility artefacts which results in geometric and intensity distortions of the acquired image. The use of these distorted images for neuro-navigation hampers the effectiveness of image-guided surgery systems as critical white matter tracts and functionally eloquent brain areas cannot be accurately localised. In this paper, we present a novel method for correction of distortions arising from susceptibility artefacts in EPI images. The proposed method combines fieldmap and image registration based correction techniques in a unified framework. A phase unwrapping algorithm is presented that can efficiently compute the B 0 magnetic field inhomo-geneity map as well as the uncertainty associated with the estimated solution through the use of dynamic graph cuts. This information is fed to a subsequent image registration step to further refine the results in areas with high uncertainty. This work has been integrated into the surgical workflow at the National Hospital for Neurology and Neurosurgery and its effectiveness in correcting for geometric distortions due to susceptibility artefacts is demonstrated on EPI images acquired with an interventional MRI scanner during neurosurgery.
    Medical Image Analysis 10/2014; 18(7):1132 - 1142. DOI:10.1016/j.media.2014.06.008 · 3.68 Impact Factor
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    ABSTRACT: Purpose To investigate the utility of 18F-fluorodeoxyglucose Positron Emission Tomography (FDG-PET) in helping decision making for epilepsy surgery Methods All patients with medically refractory focal epilepsy and MRI that was normal or discordant with clinical and EEG data underwent FDG-PET. FDG-PET scans were reported by two investigators blinded to clinical data using visual assessment aided by the semiquantitative assessment. All clinical, MRI and FDG-PET data were reviewed in the multidisciplinary patient management conferences for the localization and further decisions, which were recorded in the electronic database. For this study, we reviewed the charts of all these patients to decide the usefulness of PET in further decision making. FDG-PET was considered to be useful if led directly to surgery, helped in planning intracranial EEG or helped in excluding patients from further evaluation. Results 194 consecutive adult patients (median age, 32.5 years) underwent FDG-PET; 158 had normal MRI, 12 had subtle MRI abnormalities and 24 had discordant noninvasive data. Final localization was temporal lobe epilepsy (TLE, n = 64), frontal lobe epilepsy (FLE, n = 66), temporal-plus epilepsy (n = 26) and other extratemporal lobe epilepsies (ETE, n = 38). PET scans were normal in 72(37%) patients, showed unifocal hypometabolism in 98(50.5%) and bilateral hypometabolism in 24(12%) patients. The TLE group had a higher proportion of abnormal PET scans (67%) than FLE (52%) and ETE (61%). PET data were useful in 103(53%) patients, more in TLE (63%) than FLE (38%) or ETE (50%). It led directly to surgery in 12(6%) cases, helped in planning intracranial EEG in 67(35%) patients and excluded 24(12%) patients from further evaluation. Focal hypometabolism on FDG-PET increased the odds of being selected for surgery or intracranial EEG by five fold [odds ratio, 5.1(2.8-9.4); p < 0.0001]. Conclusions FDG-PET scan can help decision making in 53% of presurgical patients with normal or discordant MRI. PET findings need to be evaluated in conjunction with other data.
    Epilepsy Research 10/2014; 108(8). DOI:10.1016/j.eplepsyres.2014.06.012 · 2.19 Impact Factor
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    ABSTRACT: Objective: We used functional MRI (fMRI) and a left-lateralizing verbal and a right-lateralizing visual-spatial working memory (WM) paradigm to investigate the effects of levetiracetam (LEV) on cognitive network activations in patients with drug-resistant temporal lobe epilepsy (TLE). Methods: In a retrospective study, we compared task-related fMRI activations and deactivations in 53 patients with left and 54 patients with right TLE treated with (59) or without (48) LEV. In patients on LEV, activation patterns were correlated with the daily LEV dose. Results: We isolated task-and syndrome-specific effects. Patients on LEV showed normaliza-tion of functional network deactivations in the right temporal lobe in right TLE during the right-lateralizing visual-spatial task and in the left temporal lobe in left TLE during the verbal task. In a post hoc analysis, a significant dose-dependent effect was demonstrated in right TLE during the visual-spatial WM task: the lower the LEV dose, the greater the abnormal right hippocampal activation. At a less stringent threshold (p , 0.05, uncorrected for multiple comparisons), a similar dose effect was observed in left TLE during the verbal task: both hippocampi were more abnormally activated in patients with lower doses, but more promi-nently on the left. Conclusions: Our findings suggest that LEV is associated with restoration of normal activation
    Neurology 09/2014; 83(17). DOI:10.1212/WNL.0000000000000910 · 8.30 Impact Factor
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    ABSTRACT: Temporal lobe epilepsy (TLE) can be conceptualized as a network disease. The network can be characterized by inter-regional functional connectivity, i.e., blood oxygen level-dependent (BOLD) signal correlations between any two regions. However, functional connectivity is not constant over time, thus computing correlation at a given time and then at some later time could give different results (non-stationarity). We hypothesized (1) that non-stationarities can be induced by epilepsy (e.g., interictal epileptic activity) increasing local signal variance and that (2) these transient events contribute to fluctuations in connectivity leading to pathological functioning, i.e., TLE semiology. We analyzed fMRI data from 27 patients with TLE and 22 healthy controls focusing on EEG-confirmed wake epochs only to protect against sleep-induced connectivity changes. Testing hypothesis (1), we identified brain regions where the BOLD signal variance was significantly greater in TLE than in controls: the temporal pole - including the hippocampus. Taking the latter as the seed region and testing hypothesis (2), we calculated the time-varying inter-regional correlation values (dynamic functional connectivity) to other brain regions and found greater connectivity variance in the TLE than the control group mainly in the precuneus, the supplementary and sensorimotor, and the frontal cortices. We conclude that the highest BOLD signal variance in the hippocampi is highly suggestive of a specific epilepsy-related effect. The altered connectivity dynamics in TLE patients might help to explain the hallmark semiological features of dyscognitive seizures including impaired consciousness (precuneus, frontal cortex), sensory disturbance, and motor automatisms (sensorimotor cortices, supplementary motor cortex). Accounting for the non-stationarity and state-dependence of functional connectivity are a prerequisite in the search for potential connectivity-derived biomarkers in TLE.
    Frontiers in Neurology 09/2014; 5:175. DOI:10.3389/fneur.2014.00175

Publication Stats

24k Citations
3,343.02 Total Impact Points

Institutions

  • 2003–2015
    • UCL Eastman Dental Institute
      Londinium, England, United Kingdom
  • 1998–2015
    • MRC Cognition and Brain Sciences Unit
      Cambridge, England, United Kingdom
    • Humboldt-Universität zu Berlin
      Berlín, Berlin, Germany
    • University of Bristol
      Bristol, England, United Kingdom
  • 2014
    • MRC Clinical Sciences Centre
      London Borough of Harrow, England, United Kingdom
  • 2009–2014
    • University of Oxford
      • Department of Experimental Psychology
      Oxford, England, United Kingdom
  • 1999–2014
    • University College London
      • • Department of Clinical and Experimental Epilepsy
      • • Institute of Neurology
      • • Institute of Cognitive Neuroscience
      Londinium, England, United Kingdom
  • 1996–2014
    • Epilepsy Society
      United Kingdom
  • 2013
    • Macquarie University
      Sydney, New South Wales, Australia
    • The University of Manchester
      Manchester, England, United Kingdom
  • 1996–2013
    • University of Cambridge
      • MRC Cognition and Brain Sciences Unit
      Cambridge, England, United Kingdom
  • 2011
    • Cuban Neurosciences Center
      La Habana, La Habana, Cuba
    • Assistance Publique Hôpitaux de Marseille
      Marsiglia, Provence-Alpes-Côte d'Azur, France
  • 2008–2011
    • Imperial College London
      • Department of Electrical and Electronic Engineering
      Londinium, England, United Kingdom
  • 2010
    • East London NHS Foundation Trust
      Londinium, England, United Kingdom
  • 2007
    • Queen Mary, University of London
      Londinium, England, United Kingdom
  • 2003–2005
    • Mrc Harwell
      Oxford, England, United Kingdom
  • 1994–2005
    • London Research Institute
      Londinium, England, United Kingdom
    • Institute for Child Health Policy (ICHP)
      Franklin Square, New York, United States
    • The University of Calgary
      • Department of Psychology
      Calgary, Alberta, Canada
  • 2002
    • Imperial Valley College
      IPL, California, United States
  • 2000
    • University of Freiburg
      Freiburg, Baden-Württemberg, Germany
  • 1996–1998
    • Great Ormond Street Hospital for Children NHS Foundation Trust
      • Department of Radiology
      Londinium, England, United Kingdom
  • 1994–1998
    • Ealing, Hammersmith & West London College
      Londinium, England, United Kingdom
  • 1997
    • Leiden University
      Leyden, South Holland, Netherlands
  • 1994–1997
    • University of Birmingham
      • School of Psychology
      Birmingham, England, United Kingdom
  • 1993–1997
    • University of London
      Londinium, England, United Kingdom