Histopathologic subtype of hippocampal sclerosis and episodic memory performance before and after temporal lobectomy for epilepsy

Saghafi, Shahram; Ferguson, Lisa; Hogue, Olivia; Gales, Jordan; Prayson, Richard A.; Busch, Robyn M.

doi:10.1111/epi.14036

Cited by 14 publications

(15 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The replication of this relationship confirms the association between total hippocampal volume and episodic memory performance in aging. Prior data in patient populations with hippocampal sclerosis and hippocampal degeneration have also demonstrated the role of hippocampal volume in episodic memory (Sexton et al, 2010;Saghafi et al, 2018). However, our larger sample did not show a relationship between total hippocampal volume and processing speed, which O'Shea et al (2016) found to be at near the same magnitude as episodic memory.…”

Section: Total Hippocampal Volume and Nihtb-cbcontrasting

confidence: 64%

Contributions of Hippocampal Volume to Cognition in Healthy Older Adults

Hardcastle

O’Shea

Kraft

et al. 2020

Front. Aging Neurosci.

View full text Add to dashboard Cite

Objective: The association between hippocampal volume and memory is continuing to be characterized in healthy older adults. Prior research suggests smaller hippocampal volume in healthy older adults is associated with poorer episodic memory and processing speed, as well as working memory, verbal learning, and executive functioning as measured by the NIH Toolbox Fluid (Fluid Cognition Composite, FCC) and Crystalized Cognition Composites (CCC). This study aimed to replicate these findings and to evaluate the association between: (1) hippocampal asymmetry index and cognition; and (2) independent contributions of the left and right hippocampal volume and cognition in a large sample of healthy older adults. Participants and Methods: One-hundred and eighty-three healthy older adults (M age = 71.72, SD = 5.3) received a T1-weighted sequence on a 3T scanner. Hippocampal subfields were extracted using FreeSurfer 6.0 and combined to provide left, right, and total hippocampal volumes. FCC subtests include Dimensional Change Card Sort, Flanker Inhibitory Control and Attention, List Sorting, Picture Sequence Memory, and Pattern Comparison. CCC subtests include Picture Vocabulary and Oral Reading Recognition. Multiple linear regressions were performed predicting cognition composites from the total, left and right, and asymmetry of hippocampal volume, controlling for sex, education, scanner, and total intracranial volume. Multiple comparisons in primary analyses were corrected using a false discovery rate (FDR) of p < 0.05.

show abstract

Section: Total Hippocampal Volume and Nihtb-cbcontrasting

confidence: 64%

Contributions of Hippocampal Volume to Cognition in Healthy Older Adults

Hardcastle

O’Shea

Kraft

et al. 2020

Front. Aging Neurosci.

View full text Add to dashboard Cite

show abstract

“…Given the disparities between clinical series, there is no consensus on whether neuronal loss progresses over time (Bl€ umcke et al, 2009;Davies et al, 1996). In addition, individual variabilities and anatomical inhomogeneities complicate classification (Coras et al, 2014;Rodrigues et al, 2015;Saghafi et al, 2018). For instance, patchy neuronal loss has been described in the CA1 region in some cases, whereas in others, it seems to adopt a more laminar profile (Prada Jardim et al, 2018).…”

Section: Introductionmentioning

confidence: 99%

Sublayer- and cell-type-specific neurodegenerative transcriptional trajectories in hippocampal sclerosis

et al. 2021

View full text Add to dashboard Cite

Sublayer-and cell-type-specific neurodegenerative transcriptional trajectories in hippocampal sclerosisGraphical abstract Highlights d Superficial CA1 pyramidal neurons are overactive in epileptic rodents d Neurodegeneration-related gene signatures progress radially in the epileptic CA1 d Larger vulnerability of superficial CA1 pyramidal cells in experimental epilepsy d Cell-type-specific disease trajectories characterize hippocampal

show abstract

“…In patients presenting types I and III, there is also neuronal loss in the dentate gyrus (DG) and, to a lesser extent, in CA3, contributing to a more severe loss of mnemonic function, which practically disappears if the loss of granule cells is higher than 60% ( 16 ). Nonetheless, other authors have reported that while patients with type II MTLE-HS pathology showed better group memory performance than those with type I MTLE-HS, almost half of them exhibited moderate to severe impairment in episodic memory tests ( 17 – 20 ).…”

Section: Introductionmentioning

confidence: 89%

Morphometric and microstructural characteristics of hippocampal subfields in mesial temporal lobe epilepsy and their correlates with mnemonic discrimination

Garcia-Munoz

Alemán‐Gómez²,

Toledano³

et al. 2023

Front. Neurol.

View full text Add to dashboard Cite

IntroductionPattern separation (PS) is a fundamental aspect of memory creation that defines the ability to transform similar memory representations into distinct ones, so they do not overlap when storing and retrieving them. Experimental evidence in animal models and the study of other human pathologies have demonstrated the role of the hippocampus in PS, in particular of the dentate gyrus (DG) and CA3. Patients with mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HE) commonly report mnemonic deficits that have been associated with failures in PS. However, the link between these impairments and the integrity of the hippocampal subfields in these patients has not yet been determined. The aim of this work is to explore the association between the ability to perform mnemonic functions and the integrity of hippocampal CA1, CA3, and DG in patients with unilateral MTLE-HE.MethodTo reach this goal we evaluated the memory of patients with an improved object mnemonic similarity test. We then analyzed the hippocampal complex structural and microstructural integrity using diffusion weighted imaging.ResultsOur results indicate that patients with unilateral MTLE-HE present alterations in both volume and microstructural properties at the level of the hippocampal subfields DG, CA1, CA3, and the subiculum, that sometimes depend on the lateralization of their epileptic focus. However, none of the specific changes was found to be directly related to the performance of the patients in a pattern separation task, which might indicate a contribution of various alterations to the mnemonic deficits or the key contribution of other structures to the function.Discussionwe established for the first time the alterations in both the volume and the microstructure at the level of the hippocampal subfields in a group of unilateral MTLE patients. We observed that these changes are greater in the DG and CA1 at the macrostructural level, and in CA3 and CA1 in the microstructural level. None of these changes had a direct relation to the performance of the patients in a pattern separation task, which suggests a contribution of various alterations to the loss of function.

show abstract

Histopathologic subtype of hippocampal sclerosis and episodic memory performance before and after temporal lobectomy for epilepsy

Cited by 14 publications

References 21 publications

Contributions of Hippocampal Volume to Cognition in Healthy Older Adults

Contributions of Hippocampal Volume to Cognition in Healthy Older Adults

Sublayer- and cell-type-specific neurodegenerative transcriptional trajectories in hippocampal sclerosis

Morphometric and microstructural characteristics of hippocampal subfields in mesial temporal lobe epilepsy and their correlates with mnemonic discrimination

Contact Info

Product

Resources

About