Temporal lobe epilepsy and memory

OBJECTIVE: Interictal blood-brain barrier dysfunction in chronic epilepsy has been demonstrated in animal models and pathological specimens. Ictal blood-brain barrier dysfunction has been shown in humans in vivo using an experimental quantitative magnetic resonance imaging (MRI) protocol. Here, we hypothesized that interictal blood-brain barrier dysfunction is also present in people with drug-resistant epilepsy. METHODS: Thirty-nine people (21 females, mean age at MRI ± SD = 30 ± 8 years) with drug-resistant epilepsy were prospectively recruited and underwent interictal T1-relaxometry before and after administration of a paramagnetic contrast agent...

High frequency anterior nucleus of the thalamus deep brain stimulation (ANT DBS) is an established therapy for treatment resistant focal epilepsies. Although high frequency-ANT DBS is well tolerated, patients are rarely seizure free and the efficacy of other DBS parameters and their impact on comorbidities of epilepsy such as depression and memory dysfunction remain unclear. The purpose of this study was to assess the impact of low vs high frequency ANT DBS on verbal memory and self-reported anxiety and depression symptoms...

OBJECTIVE: Demographic and disease factors are associated with cognitive deficits and postoperative cognitive declines in adults with pharmacoresistant temporal lobe epilepsy (TLE), but the role of genetic factors in cognition in TLE is not well understood. Polygenic scores (PGS) for neurological and neuropsychiatric disorders and IQ have been associated with cognition in patient and healthy populations. In this exploratory study, we examined the relationship between PGS for Alzheimer's disease (AD), depression, and IQ and cognitive outcomes in adults with TLE...

AIM OF THE STUDY: To assess whether the middle temporal gyrus (MTG) approach to mesial temporal lobe (MTL) tumours is an effective procedure for the treatment of epilepsy in children. CLINICAL RATIONALE FOR THE STUDY: MTL tumours are a common cause of drug-resistant epilepsy in children. There is as yet no consensus regarding their treatment. One possibility is resection via a MTG approach. MATERIAL AND METHODS: We assessed the medical records of patients treated at the Department of Neurosurgery, Children's Memorial Health Institute,Warsaw, Poland between 2002 and 2020...

OBJECTIVE: In temporal lobe epilepsy (TLE), a taxonomy classifying patients into 3 cognitive phenotypes has been adopted: minimally, focally, or multidomain cognitively impaired (CI). We examined gray matter (GM) thickness patterns of cognitive phenotypes in drug-resistant TLE and assessed potential use for predicting postsurgical cognitive outcomes. METHODS: TLE patients undergoing presurgical evaluation were categorized into cognitive phenotypes. Network edge weights and distances were calculated using type III analysis of variance F-statistics from comparisons of GM regions within each TLE cognitive phenotype and age- and sex-matched healthy participants...

Anti-seizure drugs (ASDs) are the first choice for the treatment of epilepsy, but there is still one-third of patients with epilepsy (PWEs) who are resistant to two or more appropriately chosen ASDs, named drug-resistant epilepsy (DRE). Temporal lobe epilepsy (TLE), a common type of epilepsy usually associated with hippocampal sclerosis (HS), shares the highest proportion of drug resistance (approximately 70%). In view of the key role of the temporal lobe in memory, emotion, and other physiological functions, patients with drug-resistant temporal lobe epilepsy (DR-TLE) are often accompanied by serious complications, and surgical procedures also yield extra considerations...

PURPOSE: Reduced glucose metabolism in the hippocampus is commonly observed in cases of medial temporal lobe epilepsy (MTLE) with hippocampal sclerosis (HS). Glucose metabolism among the various hippocampal subfields has not been thoroughly investigated. PATIENTS AND METHODS: This study examined 29 patients (18 females; 15-58 years) diagnosed with HS who underwent surgery for drug-resistant epilepsy. FreeSurfer 7.1.1 was used in the processing of MRI data and 18F-FDG PET scans to derive volumetric data and the FDG SUVr in the whole hippocampus and hippocampal subfields, including the CA1, CA2-4, granule cell and molecular layer of the dentate gyrus (GC-ML-DG), and subiculum...

Temporal lobe epilepsy (TLE) is a common neurological disease characterized by recurrent focal seizures. These seizures often originate from the mesial temporal limbic networks and the parahippocampal neocortex. People with TLE frequently experience comorbidities related to memory, mood, and sleep (MMS). Deep brain stimulation targeting the anterior nucleus of the thalamus (ANT-DBS) is a proven therapy for reducing TLE seizures, but the optimal stimulation parameters for improving seizures and MMS comorbidities remains unclear...

Associative memory enables the encoding and retrieval of relations between different stimuli. To better understand its neural basis, we investigated whether associative memory involves temporally correlated spiking of medial temporal lobe (MTL) neurons that exhibit stimulus-specific tuning. Using single-neuron recordings from patients with epilepsy performing an associative object-location memory task, we identified the object-specific and place-specific neurons that represented the separate elements of each memory...

PURPOSE: To identify patients with adult-onset temporal lobe epilepsy (TLE) at risk of developing cognitive decline. Detecting which patients, aetiologies, or factors are most closely related with memory decline would allow us to identify patients that would eventually benefit from more specific treatment. METHODS: Single centre, retrospective analysis of a prospectively followed-up cohort study, including all patients with the diagnosis of adult-onset TLE during 2013, with a minimum follow-up of five years...

PURPOSE: Temporal lobe epilepsy (TLE) has a high risk of developing drug resistant and cognitive comorbidities. Adenosine has potential anticonvulsant effects as an inhibitory neurotransmitter, but drugs targeting its receptors and metabolic enzyme has inevitable side effects. Therefore, we investigated adenosine augmentation therapy for seizure control and cognitive comorbidities in TLE animals. METHODS: Using lentiviral vectors coexpressing miRNA inhibiting the expression of adenosine kinase (ADK), we produced ADK- -rMSC (ADK knockdown rat mesenchymal stem cell)...

INTRODUCTION: Verbal episodic memory (VEM) is often unimpaired in children with focal epilepsy undergoing left temporal lobe resections, unlike what we might expect in the adult brain. The latter findings suggest that epileptiform activity in early life disrupts memory system lateralization, leading to the development of bilateral memory representation. The present study aims to analyze whether the laterality of epilepsy is a major predictor for post-operative VEM prognosis in pediatric temporal lobe epilepsy (TLE) surgery...

OBJECTIVE: Electroencephalographic (EEG) microstate abnormalities have been documented in different neurological disorders. We aimed to assess whether EEG microstates are altered also in patients with temporal epilepsy (TLE) and whether they show different activations in patients with unilateral TLE (UTLE) and bilateral TLE (BTLE). METHODS: Nineteen patients with UTLE, 12 with BTLE, and 15 healthy controls were enrolled. Resting state high-density electroencephalography (128 channels) was recorded for 15 min with closed eyes...

BACKGROUND:  Multiple hippocampal transection (MHT) is a surgical technique used for the treatment of drug-resistant mesial temporal lobe epilepsy in situations where standard procedures would pose a high risk for memory deterioration. During MHT, the longitudinal fibers of the hippocampus, implicated in epilepsy spreading, are interrupted, while the transverse memory circuits are spared. The extent of MHT is governed by intraoperative electrocorticography; abolition of epileptic discharges serves as an end point to terminate the transection...

Epilepsy, especially the medial temporal lobe epilepsy (TLE), can result in cognitive impairment. Low‑frequency repetitive magnetic stimulation (rTMS) has been verified to suppress neural excitability and reduce seizures. Given its potential in modifying cortical activity, we aimed to investigate its impact on cognitive function in the context of epilepsy, a condition where the use of rTMS has not been extensively explored. However, the influence on cognitive function has not yet been investigated. Therefore, this study aimed to investigate the effects of low‑frequency rTMS on cognitive improvement in epileptic rats...

BACKGROUND: With expanding neurosurgical options in epilepsy, it is important to characterise each options' risk for postoperative cognitive decline. Here, we characterise how patients' preoperative white matter (WM) networks relates to postoperative memory changes following different epilepsy surgeries. METHODS: Eighty-nine patients with temporal lobe epilepsy with T1-weighted and diffusion-weighted imaging as well as preoperative and postoperative verbal memory scores (prose recall) underwent either anterior temporal lobectomy (ATL: n=38) or stereotactic laser amygdalohippocampotomy (SLAH; n=51)...

OBJECTIVE: Individuals with temporal lobe epilepsy (TLE) frequently demonstrate impairments in executive function, working memory, and/or declarative memory. It is recommended that screening for cognitive impairment is undertaken in all people newly diagnosed with epilepsy. However, standard neuropsychological assessments are a limited resource and thus not available to all. Our study investigated the use of robotic technology (the Kinarm robot) for cognitive screening. METHODS: 27 participants with TLE (17 left) underwent both a brief neuropsychological screening and a robotic (Kinarm) assessment...

PURPOSE: The hippocampus is organized in subfields (HSF) involved in learning and memory processes and widely implicated in pathologies at different ages of life, from neonatal hypoxia to temporal lobe epilepsy or Alzheimer's disease. Getting a highly accurate and robust delineation of sub-millimetric regions such as HSF to investigate anatomo-functional hypotheses is a challenge. One of the main difficulties encountered by those methodologies is related to the small size and anatomical variability of HSF, resulting in the scarcity of manual data labeling...

INTRODUCTION: Temporal Lobe Epilepsy (TLE) has been associated with memory impairments, which are typically linked to hippocampal and mesial temporal cortex lesions. Considering the presence of extensive bidirectional frontotemporal connections, it can be hypothesized that executive dysfunction in TLE is modulated by the lateralization of the epileptic foci. MATERIAL AND METHODS: A comprehensive neuropsychological executive functions protocol was administered to 63 participants, including 42 individuals with temporal lobe epilepsy (20 with right-TLE and 22 with left-TLE) and 21 healthy controls aged 20-49...

Neuropsychological outcomes following temporal lobe resection for drug-resistant epilepsy (DRE) are well established. For instance, left anterior temporal lobectomy (LATL) is associated with a greater risk for cognitive morbidity compared to right (RATL). However, the impact of neuromodulatory devices, specifically responsive neurostimulation (RNS), remains an area of active interest. There are currently no head-to-head comparisons of neuropsychological outcomes after surgical resection and neuromodulation...