We report a characteristic pattern of neuropathological change in the entorhinal cortex (EC) from four patients with temporal lobe epilepsy. Specimens of the EC were obtained during the surgical treatment of intractable partial seizures and were studied by light microscopy in Nissl-stained sections. A distinct loss of neurons was observed in the anterior portion of the medial EC in the absence of apparent damage to temporal neocortical gyri. Cell loss was most pronounced in layer III, but also noticed in layer II, particularly in the rostral field. A similar pattern of neurodegeneration in the EC was found in all specimens examined though the degree of neuronal loss varied between cases. These observations provide neuropathological evidence for an involvement of the EC in temporal lobe epilepsy. Since the EC occupies a pivotal position in gating hippocampal input and output, our results further support previous suggestions that dysfunction of this region may contribute, either independently or in concert with Ammon's horn sclerosis, to epileptogenesis in humans.
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Cell Rep
January 2025
Nash Family Department of Neuroscience, The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA. Electronic address:
Temporal lobe epilepsy (TLE) causes pervasive and progressive memory impairments, yet the specific circuit changes that drive these deficits remain unclear. To investigate how hippocampal-entorhinal dysfunction contributes to progressive memory deficits in epilepsy, we performed simultaneous in vivo electrophysiology in the hippocampus (HPC) and medial entorhinal cortex (MEC) of control and epileptic mice 3 or 8 weeks after pilocarpine-induced status epilepticus (Pilo-SE). We found that HPC synchronization deficits (including reduced theta power, coherence, and altered interneuron spike timing) emerged within 3 weeks of Pilo-SE, aligning with early-onset, relatively subtle memory deficits.
View Article and Find Full Text PDFMed Sci (Basel)
January 2025
Department of Medical Genetics, Clinical Neurophysiology of Postgraduate Education, V.F. Voyno-Yasenetsky Krasnoyarsk State Medical University, Russian National Research, Krasnoyarsk 660022, Russia.
: Epilepsy is a group of disorders characterized by a cluster of clinical and EEG signs leading to the formation of abnormal synchronous excitation of neurons in the brain. It is one of the most common neurological disorders worldwide; and is characterized by aberrant expression patterns; both at the level of matrix transcripts and at the level of regulatory RNA sequences. Aberrant expression of a number of microRNAs can mark a particular epileptic syndrome; which will improve the quality of differential diagnosis.
View Article and Find Full Text PDFNeuroSci
January 2025
Department of Neuroscience "Rita Levi Montalcini", University of Turin, 10126 Turin, Italy.
Dementia, including Alzheimer's disease (AD) and frontotemporal dementia (FTD), presents critical challenges for correctional systems, particularly as global populations age. AD, affecting 60-80% of dementia cases, primarily impairs memory and cognition in individuals over 65. In contrast, FTD, rarer than AD but not uncommon in those under 65, affects the frontal and temporal brain regions, leading to deficits in social behavior, language, and impulse control, often resulting in antisocial actions and legal consequences.
View Article and Find Full Text PDFBrain Commun
January 2025
Department of Clinical Psychology and Psychobiology, Universidade de Santiago de Compostela (USC), Santiago de Compostela 15782, Spain.
Previous research has revealed patterns of brain atrophy in subjective cognitive decline, a potential preclinical stage of Alzheimer's disease. However, the involvement of myelin content and microstructural alterations in subjective cognitive decline has not previously been investigated. This study included three groups of participants recruited from the Compostela Aging Study project: 53 cognitively unimpaired adults, 16 individuals with subjective cognitive decline and hippocampal atrophy and 70 with subjective cognitive decline and no hippocampal atrophy.
View Article and Find Full Text PDFIBRO Neurosci Rep
June 2025
Department of Pharmacy, University of Mountains, P.O. Box 208, Bangangté, Cameroon.
Background And Aim: To date, there is no treatment to prevent the development of temporal lobe epilepsy, the most common form of drug-resistant epilepsy. A recent study revealed the antiepileptic-like effect of the aqueous extract of . Given the potential of this extract, the antiepileptogenic- and learning and memory-facilitating-like effects of the aqueous extract of were assessed using the kainate-induced post- model.
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