Individual Seizure Research Articles

Altered Functional Connectivity after Epileptic Seizure Revealed by Scalp EEG.

Epileptic seizures are considered to be a brain network dysfunction, and chronic recurrent seizures can cause severe brain damage. However, the functional brain network underlying recurrent epileptic seizures is still left unveiled. This study is aimed at exploring the differences in a related brain activity before and after chronic repetitive seizures by investigating the power spectral density (PSD), fuzzy entropy, and functional connectivity in epileptic patients. The PSD analysis revealed differences between the two states at local area, showing postseizure energy accumulation. Besides, the fuzzy entropies of preseizure in the frontal, central, and temporal regions are higher than that of postseizure. Additionally, attenuated long-range connectivity and enhanced local connectivity were also found. Moreover, significant correlations were found between network metrics (i.e., characteristic path length and clustering coefficient) and individual seizure number. The PSD, fuzzy entropy, and network analysis may indicate that the brain is gradually impaired along with the occurrence of epilepsy, and the accumulated effect of brain impairment is observed in individuals with consecutive epileptic bursts. The findings of this study may provide helpful insights into understanding the network mechanism underlying chronic recurrent epilepsy.

Management of patients with single and rare epileptic seizures

Objective: to study the structure of the disease and develop tactics of treatment of patients with single and rare epileptic seizures. Materials and methods. 1200 patients with epilepsy were examined, 103 patients were identified who had no more than 3 seizures throughout their life. Study included evaluation of anamnesis, clinical and neurological examination, routine electroencephalography and/or videoelectroencephalographic monitoring, magnetic resonance imaging of the brain. Results. Relapse of seizures in individuals with a history of follow-up occurred in 32 % of cases; epileptogenic changes in magnetic resonance image and, especially, anatomical and electro-clinical correlation of the epilepsy focus were associated with the risk of relapse. Conclusions. The decision on drug therapy after the first unprovoked seizure should be based on the ratio of the risk of repeated seizures and the risk of side effects. This solution should be individual and take into account not only medical problems, but also the preferences of the patient and his family members.

Novel brain permeant mTORC1/2 inhibitors are as efficacious as rapamycin or everolimus in mouse models of acquired partial epilepsy and tuberous sclerosis complex

Mechanistic target of rapamycin (mTOR) regulates cell proliferation, growth and survival, and is activated in cancer and neurological disorders, including epilepsy. The rapamycin derivative (“rapalog”) everolimus, which allosterically inhibits the mTOR pathway, is approved for the treatment of partial epilepsy with spontaneous recurrent seizures (SRS) in individuals with tuberous sclerosis complex (TSC). In contrast to the efficacy in TSC, the efficacy of rapalogs on SRS in other types of epilepsy is equivocal. Furthermore, rapalogs only poorly penetrate into the brain and are associated with peripheral adverse effects, which may compromise their therapeutic efficacy. Here we compare the antiseizure efficacy of two novel, brain-permeable ATP-competitive and selective mTORC1/2 inhibitors, PQR620 and PQR626, and the selective dual pan-PI3K/mTORC1/2 inhibitor PQR530 in two mouse models of chronic epilepsy with SRS, the intrahippocampal kainate (IHK) mouse model of acquired temporal lobe epilepsy and Tsc1GFAP CKO mice, a well-characterized mouse model of epilepsy in TSC. During prolonged treatment of IHK mice with rapamycin, everolimus, PQR620, PQR626, or PQR530; only PQR620 exerted a transient antiseizure effect on SRS, at well tolerated doses whereas the other compounds were ineffective. In contrast, all of the examined compounds markedly suppressed SRS in Tsc1GFAP CKO mice during chronic treatment at well tolerated doses. Thus, against our expectation, no clear differences in antiseizure efficacy were found across the three classes of mTOR inhibitors examined in mouse models of genetic and acquired epilepsies. The main advantage of the novel 1,3,5-triazine derivatives is their excellent tolerability compared to rapalogs, which would favor their development as new therapies for TORopathies such as TSC.

Idiopathic epilepsy in dogs: insights into factors that may predict upcoming seizure activity

Idiopathic epilepsy (IE) is the most common chronic neurological disorder in dogs. Most dogs with IE first experience seizures when they are under six years old, and they usually require...

Total Charge Required to Induce a Seizure in a Retrospective Cohort of Patients Undergoing Dose Titration of Right Unilateral Ultrabrief Pulse Electroconvulsive Therapy.

The use of ultrabrief pulse (UBP) stimuli and individual seizure threshold determination have been proposed as ways of minimizing the cognitive side effects of electroconvulsive therapy (ECT), but large samples of patients receiving UBP ECT are lacking. This study reports a retrospective cohort of patients receiving an index course of right unilateral UBP ECT and characterizes the amount of charge required to induce a seizure. A single-center retrospective chart review was conducted of adult patients receiving a first lifetime course of ECT using an UBP titration from 2005 to 2017. There were 2328 patients that received a dose titration during the study period, with a mean dose of 21.82 ± 21.61 mC applied to induce a seizure. During the early part of the study period, a mean dose of 18.73 ± 8.99 mC was used, with 28% of patients seizing at a dose of less than 19.2 mC. In the later period, the initial step of dose titration was standardized at 19.2 mC, yielding a mean initial dose to induce a seizure of 22.72 ± 24.00 mC. Mean seizure thresholds may be lower than reported in previous studies, and a significant proportion of patients may have a seizure threshold lower than the first step of many existing dose titration protocols.

Seizure forecasting and cyclic control of seizures.

Epilepsy is a unique neurologic condition characterized by recurrent seizures, where causes, underlying biomarkers, triggers, and patterns differ across individuals. The unpredictability of seizures can heighten fear and anxiety in people with epilepsy, making it difficult to take part in day-to-day activities. Epilepsy researchers have prioritized developing seizure prediction algorithms to combat episodic seizures for decades, but the utility and effectiveness of prediction algorithms has not been investigated thoroughly in clinical settings. In contrast, seizure forecasts, which theoretically provide the probability of a seizure at any time (as opposed to predicting the next seizure occurrence), may be more feasible. Many advances have been made over the past decade in the field of seizure forecasting, including improvements in algorithms as a result of machine learning and exploration of non-EEG-based measures of seizure susceptibility, such as physiological biomarkers, behavioral changes, environmental drivers, and cyclic seizure patterns. For example, recent work investigating periodicities in individual seizure patterns has determined that more than 90% of people have circadian rhythms in their seizures, and many also experience multiday, weekly, or longer cycles. Other potential indicators of seizure susceptibility include stress levels, heart rate, and sleep quality, all of which have the potential to be captured noninvasively over long time scales. There are many possible applications of a seizure-forecasting device, including improving quality of life for people with epilepsy, guiding treatment plans and medication titration, optimizing presurgical monitoring, and focusing scientific research. To realize this potential, it is vital to better understand the user requirements of a seizure-forecasting device, continue to advance forecasting algorithms, and design clear guidelines for prospective clinical trials of seizure forecasting.

Daily listening to Mozart reduces seizures in individuals with epilepsy: A randomized control study.

ObjectiveEpilepsy is one of the most common neurological disorders . Many individuals continue to have seizures despite medical and surgical treatments, suggesting adjunctive management strategies are required. Promising effects of daily listening to Mozart on reducing seizure frequency in individuals with epilepsy have been demonstrated over the last 20 years, but not in a rigorously controlled manner. In this study, we compared the effect on seizure frequency of daily listening to either Mozart K.448 or a spectrally similar, yet non‐rhythmic control piece. We hypothesized that there would be no difference in seizure counts when participants listened to Mozart K.448 vs when they listened to the control piece.MethodsWe employed a randomized crossover design, in which each participant was exposed to both three months of daily listening to the first six minutes of Sonata for two pianos in D major by Mozart (Mozart K.448; treatment period) and three months of daily listening to phase‐scrambled version (control period). There was a three‐month baseline and a three‐month follow‐up period before and after the six‐month listening period, respectively. Change in seizure counts obtained from the seizure diaries was considered as the main study outcome.ResultsUsing three methodologies to investigate the existence of the treatment effect (paired t test, estimation statistics and plots, and Cohen's d), our results revealed a reduction in seizure counts during the treatment period, which was not observed for the control period (P‐value < .001).SignificanceUsing a spectrally similar control piece, our study advances previous reports that were limited by a “no music” control condition. Daily listening to Mozart K.448 was associated with reducing seizure frequency in adult individuals with epilepsy. These results suggest that daily Mozart listening may be considered as an adjunctive therapeutic option to reduce seizure burden in individuals with epilepsy.

Post‐ictal accelerometer silence as a marker of post‐ictal immobility

Movement-based wearable sensors are used for detection of convulsive seizures. The identification of the absence of motion following a seizure, known as post-ictal immobility (PI), may represent a potential additional application of wearables. PI has been associated with potentially life-threatening complications and with sudden unexpected death in epilepsy (SUDEP). We aimed to assess whether wearable accelerometers (ACCs) could be used as a digital marker of PI. Devices with embedded ACCs were worn by patients admitted to an epilepsy monitoring unit. Participants presenting with convulsive seizures were included in the study. PI presence and duration were assessed by experts reviewing video recordings. An algorithm for the automatic detection of post-ictal ACC silence and its duration was developed and the linear pairwise relationship between the automatically detected duration of post-ictal ACC silence and the duration of the expert-labeled PI was analyzed. Twenty-two convulsive seizures were recorded from 18 study participants. Twenty were followed by PI and two by agitation. The automated estimation of post-ictal ACC silence identified all the 20 expert-labeled PI. The regression showed that the duration of the post-ictal ACC silence was correlated with the duration of PI (Pearson r=.92; P<.001), with the age of study participants (Pearson r=.78; P<.001), and with the duration of post-ictal generalized electroencephalography suppression (PGES; Pearson r=.4; P=.033). We highlight a novel application of wearables as a way to record post-ictal manifestations associated with an increased risk of SUDEP. The occurrence of a fatal seizure is unpredictable and the continuous, non-invasive, long-term identification of risk factors associated with each individual seizure may assume a great clinical importance.

Seizure Detection: Interreader Agreement and Detection Algorithm Assessments Using a Large Dataset.

Purpose:To compare the seizure detection performance of three expert humans and two computer algorithms in a large set of epilepsy monitoring unit EEG recordings.Methods:One hundred twenty prolonged EEGs, 100 containing clinically reported EEG-evident seizures, were evaluated. Seizures were marked by the experts and algorithms. Pairwise sensitivity and false-positive rates were calculated for each human–human and algorithm–human pair. Differences in human pairwise performance were calculated and compared with the range of algorithm versus human performance differences as a type of statistical modified Turing test.Results:A total of 411 individual seizure events were marked by the experts in 2,805 hours of EEG. Mean, pairwise human sensitivities and false-positive rates were 84.9%, 73.7%, and 72.5%, and 1.0, 0.4, and 1.0/day, respectively. Only the Persyst 14 algorithm was comparable with humans—78.2% and 1.0/day. Evaluation of pairwise differences in sensitivity and false-positive rate demonstrated that Persyst 14 met statistical noninferiority criteria compared with the expert humans.Conclusions:Evaluating typical prolonged EEG recordings, human experts had a modest level of agreement in seizure marking and low false-positive rates. The Persyst 14 algorithm was statistically noninferior to the humans. For the first time, a seizure detection algorithm and human experts performed similarly.

Patient views on use of emergency and alternative care services for adult epilepsy: A qualitative study

PurposeEmergency Department (ED) visits are costly to the health service and alternative care pathways may address this whilst improving outcomes. We aimed to describe decision-making and preferences of people with epilepsy (PWE) during emergency service use, and views of ED alternatives, including use of an Urgent Treatment Centre and telephone-based support from an epilepsy nurse specialist. MethodsWe conducted a community-based interview study in South East England, informed by a qualitative framework approach. 25 adults with epilepsy and 5 of their carers took part. ResultsParticipants’ choice to attend ED generally corresponded with guidelines, including continuing seizures and injury. Nevertheless, over half reported unwanted or unnecessary ED attendance, mainly due to lack of access to individual patient history, a carer, or seizures occurring in a public place. Participants used proactive strategies to communicate their care needs to others, including 24 -h alarm devices and care plans. Some suggested preventative strategies including referral after ED. Participants highlighted the importance of ambulance staff in providing fast and efficient care that gives reassurance. ConclusionImproving communication and access to preventative, proactive services may facilitate better outcomes within existing care pathways. PWE felt ED alternatives were helpful in some circumstances, but Urgent Treatment Centres or epilepsy nurse specialists were not viewed as an ED replacement.

Factors Associated With Seizure Onset in Children With Autism Spectrum Disorder.

Children with autism spectrum disorder (ASD) have a higher prevalence of epilepsy compared with general populations. In this pilot study, we prospectively identified baseline risk factors for the development of seizures in individuals with ASD and also identified characteristics sensitive to seizure onset up to 6 years after enrollment in the Autism Speaks Autism Treatment Network. Children with ASD and no history of seizures at baseline who either experienced onset of seizures after enrollment in the Autism Treatment Network or remained seizure free were included in the analysis. Among 472 qualifying children, 22 (4.7%) experienced onset of seizures after enrollment. Individuals who developed seizures after enrollment exhibited lower scores at baseline on all domains of the Vineland Adaptive Behavior Scales, greater hyperactivity on the Aberrant Behavior Checklist (25.4 ± 11.8 vs 19.2 ± 11.1; P = .018), and lower physical quality of life scores on the Pediatric Quality of Life Inventory (60.1 ± 24.2 vs 76.0 ± 18.2; P < .001). Comparing change in scores from entry to call-back, adjusting for age, sex, length of follow-up, and baseline Vineland II composite score, individuals who developed seizures experienced declines in daily living skills (-8.38; 95% confidence interval -14.50 to -2.50; P = .005). Adjusting for baseline age, sex, and length of follow-up, baseline Vineland II composite score was predictive of seizure development (risk ratio = 0.95 per unit Vineland II composite score, 95% confidence interval 0.92 to 0.99; P = .007). Individuals with ASD at risk for seizures exhibited changes in adaptive functioning and behavior.

Inter-rater reliability of amplitude-integrated EEG for the detection of neonatal seizures

BackgroundAmplitude-integrated electroencephalogram (aEEG) is being used increasingly for seizure detection in neonates. However, data regarding inter-rater reliability among neonatologists for the use of aEEG for the detection of neonatal seizures is lacking. MethodsTerm and late-preterm infants at risk of seizures were monitored simultaneously with 24-h video-electroencephalography (vEEG) and aEEG. vEEG was interpreted by an experienced neurologist. Five neonatologists with experience in aEEG interpretation from four different neonatal units interpreted aEEG recordings independently. The Brennan and Prediger kappa coefficient and Intra-class Correlation Coefficients (ICC) were used to assess inter-rater reliability between the neonatologists. ResultsThirty-five infants at risk of seizure with gestational age at birth 35–42 weeks were recruited for the study after informed parental consent. vEEG detected seizures in seven infants with a total of 169 individual seizure episodes. Neonatologists detected seizures in 10 to 15 infants on aEEG. The sensitivities for the detection of individual seizures by neonatologists ranged from 18% to 38%. The inter-rater reliability for detection of: individual seizure was “fair” (kappa = 0.37; 95% CI: 0.32–0.42), infant with seizure was “moderate” (kappa = 0.60; 95% CI: 0.44–0.75), duration of individual seizure (ICC: 0.22; 95% CI: 0.18–0.28) and total duration of seizures in an infant (ICC: 0.46; 95% CI: 0.30–0.63) was “poor”. The neonatologists missed 77–90% of the duration of seizures. ConclusionThe inter-rater reliability of aEEG for the detection of neonatal seizures was suboptimal. Even when interpreted by experienced and trained clinicians, seizure detection with aEEG has limitations and can miss large number and duration of seizures.

Incidence of seizure exacerbation and injury related to football participation in people with epilepsy

IntroductionThere is scant evidence to quantify the risk of contact sports such as football to patients with epilepsy. This retrospective review was performed to evaluate the incidence of injuries or seizure exacerbation related to football participation in patients with epilepsy. MethodsBetween the years 1994 and 2004, 157,709 consecutive clinic notes were searched for mention of “football” and “epilepsy” or “seizure”. Resulting notes were reviewed to quantify the number of seizure exacerbations and the number of injuries in this cohort. ResultsSeven of 44 subjects with epilepsy (15.9%) experienced injury while playing football. Four of 32 (12.5%) patients experienced seizure exacerbation during a time when they were concurrently participating in football though 3 of these patients stopped taking or were weaned off of their antiepileptic drugs (AEDs). One in 32 patients with epilepsy (3.1%) had an exacerbation of seizures while playing football and consistently taking AEDs. ConclusionThe risk of injury and seizure exacerbation due to participation in football for patients with epilepsy is low. Clinicians should use their best judgment in deciding whether contact sports increase risks for a particular patient based on individual seizure frequency, concurrent neurological and medical issues, and medication adverse effects.

Does Stress Trigger Seizures? Evidence from Experimental Models.

This chapter describes the experimental evidence of stress modulation of epileptic seizures and the potential role of corticosteroids and neurosteroids in regulating stress-linked seizure vulnerability. Epilepsy is a chronic neurological disorder that is characterized by repeated seizures. There are many potential causes for epilepsy, including genetic predispositions, infections, brain injury, and neurotoxicity. Stress is a known precipitating factor for seizures in individuals suffering from epilepsy. Severe acute stress and persistent exposure to stress may increase susceptibility to seizures, thereby resulting in a higher frequency of seizures. This occurs through the stress-mediated release of cortisol, which has both excitatory and proconvulsant properties. Stress also causes the release of endogenous neurosteroids from central and adrenal sources. Neurosteroids such as allopregnanolone and THDOC, which are allosteric modulators of GABA-A receptors, are powerful anticonvulsants and neuroprotectants. Acute stress increases the release of neurosteroids, while chronic stress is associated with severe neurosteroid depletion and reduced inhibition in the brain. This diminished inhibition occurs largely as a result of neurosteroid deficiencies. Thus, exogenous administration of neurosteroids (neurosteroid replacement therapy) may offer neuroprotection in epilepsy. Synthetic neurosteroid could offer a rational approach to control neurosteroid-sensitive, stress-related epileptic seizures.

A Comparison Of Conventional Electroencephalography With Amplitude-Integrated EEG In Detection Of Neonatal Seizures.

IntroductionAmplitude-integrated electroencephalogram (aEEG) is widely used in Neonatal Intensive Care Units (NICUs) to monitor neonatal seizures. This method is still not well established compared to conventional electroencephalogram (cEEG), the diagnostic gold standard. However, aEEG can be a good screening tool for the diagnosis of seizures in infants. Our aim in this review study is to evaluate aEEG diagnostic accuracy in comparison with cEEG, for detection of neonatal seizures.MethodsIn this work, we studied the published articles which used EEG and aEEG in the evaluation process of seizures in neonates and compared these techniques to obtain an approach for the detection of neonatal seizures.ResultsSeventeen articles were included. Using aEEG with raw trace to detect individual seizures showed median sensitivity of 78% (range: 68–85) and median specificity of 78% (range: 71–84). The median sensitivity and specificity were 54% (range: 25–95) and 81% (range: 50–100), respectively, in case of using aEEG without raw traces. Brief duration seizures and those occurring away from aEEG leads were less detected.ConclusionStudies showed that aEEG has variable sensitivity and specificity. Based on the evidences, aEEG cannot be recommended as the only way for diagnosis and management of seizures in neonates; however, it could complete the diagnosis of seizures in the infant and could be a very good tool for screening seizures.

Cannabidiol attenuates seizures and EEG abnormalities in Angelman syndrome model mice.

Angelman syndrome (AS) is a neurodevelopmental disorder characterized by intellectual disability, lack of speech, ataxia, EEG abnormalities, and epilepsy. Seizures in individuals with AS are common, debilitating, and often drug resistant. Thus, there is an unmet need for better treatment options. Cannabidiol (CBD), a major phytocannabinoid constituent of cannabis, has shown antiseizure activity and behavioral benefits in preclinical and clinical studies for some disorders associated with epilepsy, suggesting that the same could be true for AS. Here, we show that acute CBD (100 mg/kg) treatment attenuated hyperthermia- and acoustically induced seizures in a mouse model of AS. However, neither acute CBD nor a 2-week-long course of CBD administered immediately after a kindling protocol could halt the proepileptogenic plasticity observed in AS model mice. CBD had a dose-dependent sedative effect but did not have an impact on motor performance. CBD abrogated the enhanced intracortical local field potential power, including the delta and theta rhythms observed in AS model mice, indicating that CBD administration could also help normalize the EEG deficits observed in individuals with AS. We believe our results provide critical preclinical evidence supporting CBD treatment of seizures and alleviation of EEG abnormalities in AS and will thus help guide the rational development of CBD as a treatment for AS.

Nonepileptic seizures in individuals attending neurological services in New Zealand

ObjectivesThis study examined the demographic, social, and clinical (neurological and psychiatric) characteristics of people with psychogenic nonepileptic seizures (PNES) presenting to tertiary neurological services at Auckland District Health Board, New Zealand. MethodsElectronic notes and video-electroencephalography (video-EEG) data gathered from the telemetry unit based on synchronized acquisition (motor activity and brain electrophysiology) over a five-year period (2011 to 2015 inclusive) were retrospectively examined. Two groups were compared: people with PNES only or people with combined PNES and epileptic seizures (ES) (the group with PNES) and a control group with ES only, matched 1:1 by age and gender. ResultsSixty-six people in the group with PNES were matched with an equivalent number of ES controls. As a cohort, there was high psychiatric and medical comorbidity in both groups, but overall, those with PNES experienced higher rates than their ES counterparts. An older age of onset, female gender, and history of abuse were more frequently seen in those with PNES. Compared with controls, people with PNES more commonly had daily seizures (rather than monthly) but presented less frequently to neurology services. A high proportion of people with PNES experienced historical traumas, ongoing stressors, and disability. Almost half of the people with PNES were on antiepileptic drugs (AEDs) and received limited psychiatric or psychological input. In contrast, people with ES were more likely to be on psychotropic medication. ConclusionBoth PNES and ES are associated with high levels of psychiatric and medical comorbidity. Additionally, PNES were found to be associated with iatrogenic harm and disability. Though people with PNES and ES often have a range of associated needs, there is, however, limited access to appropriate services. The needs of these populations should be better met through enhanced integration across psychiatry, neurology, and multidisciplinary services.

When can we trust responders? Serious concerns when using 50% response rate to assess clinical trials.

Individual seizure rates are highly volatile, with large fluctuations from month-to-month. Nevertheless, changes in individual mean seizure rates are used to measure whether or not trial participants successfully respond to treatment. This study aims to quantify the challenges in identifying individual treatment responders in epilepsy. A power calculation was performed to determine the trial duration required to detect a significant 50% decrease in seizure rates (P<.05) for individuals. Seizure rate simulations were also performed to determine the number of people who would appear to be 50% responders by chance. Seizure rate statistics were derived from long-term seizure counts recorded during a previous clinical trial for an implantable seizure monitoring device. We showed that individual variance in monthly seizure rates can lead to an unacceptably high false-positive rate in the detection of individual treatment responders. This error rate cannot be reduced by increasing the trial population; however, it can be reduced by increasing the duration of clinical trials. This finding suggests that some drugs may be incorrectly evaluated as effective; or, conversely, that helpful drugs could be rejected based on 50% response rates. It is important to pursue more nuanced approaches to measuring individual treatment response, which consider the patient-specific distributions of seizure rates.

Cognitive and behavioral effects of brief seizures in mice

Comorbidities associated with epilepsy greatly reduce patients' quality of life. Since antiepilepsy drugs show limited success in ameliorating cognitive and behavioral symptoms, there is a need to better understand the mechanisms underlying epilepsy-related cognitive and behavioral impairments. Most prior research addressing this problem has focused on chronic epilepsy, wherein many factors can simultaneously impact cognition and behavior. The purpose of the present study was to develop a testing paradigm using mice that can provide new insight into how short-term biological changes underlying acute seizures impact cognition and behavior. In Experiment 1, naïve C57BL/6J mice were subjected to either three brief, generalized electroconvulsive seizure (ECS) or three sham treatments equally spaced over the course of 30 min. Over the next 2 h, mice were tested in a novel object recognition paradigm. Follow-up studies examined locomotor activity immediately before and after (Experiment 2), immediately after (Experiment 3), and 45 min after (Experiment 4) a set of three ECS or sham treatments. Whereas results demonstrated that there was no statistically significant difference in recognition memory acquisition between ECS and sham-treated mice, measures of anxiety-like behavior were increased and novel object interest was decreased in ECS-treated mice compared with that in sham. Interestingly, ECS also produced a delayed inhibitory effect on locomotion, decreasing open-field activity 45-min posttreatment compared to sham. We conclude that a small cluster of brief seizures can have acute, behaviorally relevant effects in mice, and that greater emphasis should be placed on events that take place before chronic epilepsy is established in order to better understand epilepsy-related cognitive and behavioral impairments. Future research would benefit from using the paradigms defined above to study the effects of individual seizures on mouse cognition and behavior.

Relationship between déjà vu experiences and recognition-memory impairments in temporal-lobe epilepsy

ABSTRACT Déjà vu is characterised by feelings of familiarity and concurrent awareness that this familiarity is wrong. Previous neuropsychological research has linked déjà vu during seizures in individuals with unilateral temporal-lobe epilepsy (uTLE) to rhinal-cortex abnormalities, and to recognition-memory deficits that selectively affect familiarity assessment. Here, we examined whether bilateral TLE patients with déjà vu (bTLE) show a similar pattern of performance. Using two experimental tasks, we found that bTLE patients exhibit deficits not only for familiarity but also for recollection. Relative to uTLE, this broader impairment also involved hippocampal abnormalities. Our findings confirm rhinal-cortex contributions to the generation of false familiarity in déjà vu that parallel its contributions to familiarity on recognition-memory tasks. While they do not rule out a role for recollection in identifying this familiarity as wrong, the deficits observed in bTLE patients weigh against the notion that any such role is necessary for déjà vu to occur.