P3-373: STRUCTURAL INTEGRITY OF THE MEDIAL TEMPORAL LOBE AND RECOGNITION MEMORY FOLLOWING NATURAL AND SURGICAL MENOPAUSE

Different structures within the medial-temporal lobe likely make distinct contributions to declarative memory. In particular, several current psychological and computational models of memory predict that the hippocampus and parahippocampal regions play different roles in the formation and retrieval of declarative memories [e.g., Norman, K. A., & O'Reilly, R. C. Modeling hippocampal and neocortical contributions to recognition memory: A complementary-learning systems approach. Psychological Review, 110, 611–646, 2003]. Here, we examined the neuronal firing patterns in these two regions during recognition memory. Recording directly from neurons in humans, we find that cells in both regions respond to novel stimuli with an increase in firing (excitation). However, already on the second presentation of a stimulus, neurons in these regions show very different firing patterns. In the parahippocampal region there is dramatic decrease in the number of cells responding to the stimuli, whereas in the hippocampus there is recruitment of a large subset of neurons showing inhibitory (decrease from baseline firing) responses. These results suggest that inhibition is a mechanism used by cells in the human hippocampus to support sparse coding in mnemonic processing. The findings also provide further evidence for the division of labor in the medial-temporal lobe with respect to declarative memory processes.

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Patterns of single-neuron activity during associative recognition memory in the human medial temporal lobe

NeuroImage ◽

10.1016/j.neuroimage.2020.117214 ◽

2020 ◽

Vol 221 ◽

pp. 117214

Author(s):

M. Derner ◽

G. Dehnen ◽

L. Chaieb ◽

T.P. Reber ◽

V. Borger ◽

...

Keyword(s):

Recognition Memory ◽

Temporal Lobe ◽

Medial Temporal Lobe ◽

Single Neuron ◽

Associative Recognition ◽

Neuron Activity ◽

Single Neuron Activity

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Can medial temporal lobe regions distinguish true from false? An event-related functional MRI study of veridical and illusory recognition memory

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.081082698 ◽

2001 ◽

Vol 98 (8) ◽

pp. 4805-4810 ◽

Cited By ~ 210

Author(s):

R. Cabeza ◽

S. M. Rao ◽

A. D. Wagner ◽

A. R. Mayer ◽

D. L. Schacter

Keyword(s):

Recognition Memory ◽

Functional Mri ◽

Temporal Lobe ◽

Medial Temporal Lobe ◽

Mri Study

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An Exploratory Study of the Relationship between Face Recognition Memory and the Volume of Medial Temporal Lobe Structures in Healthy Young Males

Behavioural Neurology ◽

10.1155/1998/285061 ◽

1998 ◽

Vol 11 (1) ◽

pp. 3-20 ◽

Cited By ~ 30

Author(s):

Clare E. Mackay ◽

Neil Roberts ◽

Andrew R. Mayes ◽

John J. Downes ◽

Jonathan K. Foster ◽

...

Keyword(s):

Face Recognition ◽

Recognition Memory ◽

Temporal Lobe ◽

Medial Temporal Lobe ◽

Multiple Comparisons ◽

Cerebral Hemispheres ◽

Parahippocampal Gyrus ◽

Bonferroni Correction ◽

Temporal Pole ◽

The Right

A rigorous new methodology was applied to the study of structure function relationships in the living human brain. Face recognition memory (FRM) and other cognitive measures were made in 29 healthy young male subjects (mean age = 21.7 years) and related to volumetric measurements of their cerebral hemispheres and of structures in their medial temporal lobes, obtained using the Cavalieri method in combination with high resolution Magnetic Resonance Imaging (MRI. Greatest proportional variability in volumes was found for the lateral ventricles (57%) for the cerebral hemispheres (8%) in the mean volumes of the hippocampus, parahippocampal gyrus, amygdala, caudate nucleus, temporal pole and temporal lobe on the right and left sides of the brain. The volumes of the right and left parahippocampal gyrus, temporal pole, temporal lobe, and left hippocampus were, prior to application of the Bonferroni correction to take account of 12 multiple comparisons, significantly correlated with the volume of the corresponding hemisphere (p< 0.05). The volumes of all structures were highly correlated (p< 0.0002 for all comparisons) between the two cerebral hemispheres. There were no positive relationships between structure volumes and FRM score. However, the volume of the right amygdala was, prior to application of the Bonferroni correction to take account of 38~multiple comparisons, found to be significantly smaller in the five most consistent high scorers compared to the five most consistent low scorers (t= 2.77,p= 0.025). The implications for possible relationships between healthy medial temporal lobe structures and memory are discussed.

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Phase/amplitude reset and theta-gamma interaction in the human medial temporal lobe during a continuous word recognition memory task

Hippocampus ◽

10.1002/hipo.20117 ◽

2005 ◽

Vol 15 (7) ◽

pp. 890-900 ◽

Cited By ~ 211

Author(s):

Florian Mormann ◽

Juergen Fell ◽

Nikolai Axmacher ◽

Bernd Weber ◽

Klaus Lehnertz ◽

...

Keyword(s):

Word Recognition ◽

Recognition Memory ◽

Temporal Lobe ◽

Medial Temporal Lobe ◽

Memory Task ◽

Recognition Memory Task ◽

Phase Amplitude

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Neural and behavioral correlates of episodic memory are associated with temporal discounting in older adults

10.1101/720250 ◽

2019 ◽

Cited By ~ 2

Author(s):

Karolina M. Lempert ◽

Dawn J. Mechanic-Hamilton ◽

Long Xie ◽

Laura E.M. Wisse ◽

Robin de Flores ◽

...

Keyword(s):

Older Adults ◽

Individual Differences ◽

Episodic Memory ◽

Temporal Lobe ◽

Cortical Thickness ◽

Medial Temporal Lobe ◽

Structural Integrity ◽

Temporal Discounting ◽

Risk Tolerance ◽

Trade Offs

AbstractWhen facing decisions involving trade-offs between smaller, sooner and larger, delayed rewards, people tend to discount the value of future rewards. There are substantial individual differences in this tendency toward temporal discounting, however. One neurocognitive system that may underlie these individual differences is episodic memory, given the overlap in the neural circuitry involved in imagining the future and remembering the past. Here we tested this hypothesis in older adults, including both those that were cognitively normal and those with amnestic mild cognitive impairment (MCI). We found that performance on neuropsychological measures of episodic memory retrieval was associated with temporal discounting, such that people with better memory discounted delayed rewards less. This relationship was specific to episodic memory and temporal discounting, since executive function (another cognitive ability) was unrelated to temporal discounting, and episodic memory was unrelated to risk tolerance (another decision-making preference). We also examined cortical thickness and volume in medial temporal lobe regions critical for episodic memory. Entorhinal cortical thickness was associated with reduced temporal discounting, with episodic memory performance partially mediating this association. The inclusion of MCI participants was critical to revealing these associations between episodic memory and entorhinal cortical thickness and temporal discounting. These effects were larger in the MCI group, reduced after controlling for MCI status, and statistically significant only when including MCI participants in analyses. Overall, these findings suggest that individual differences in temporal discounting are driven by episodic memory function, and that a decline in medial temporal lobe structural integrity may impact temporal discounting.

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Effects of early surgical menopause on sleep, memory, and medial temporal lobe structure at midlife

Alzheimer s & Dementia ◽

10.1002/alz.047548 ◽

2020 ◽

Vol 16 (S5) ◽

Author(s):

Nicole J Gervais ◽

Claire Lauzon ◽

Alana Brown ◽

Laura Gravelsins ◽

Gina Nicoll ◽

...

Keyword(s):

Temporal Lobe ◽

Medial Temporal Lobe ◽

Surgical Menopause

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Cross-validation of brain structural biomarkers and cognitive aging in a community-based study

International Psychogeriatrics ◽

10.1017/s1041610212000191 ◽

2012 ◽

Vol 24 (7) ◽

pp. 1065-1075 ◽

Cited By ~ 5

Author(s):

James T. Becker ◽

Ranjan Duara ◽

Ching-Wen Lee ◽

Leonid Teverovsky ◽

Beth E. Snitz ◽

...

Keyword(s):

Older Adults ◽

Temporal Lobe ◽

Cognitive Aging ◽

Medial Temporal Lobe ◽

Structural Integrity ◽

Rating Scale ◽

Hippocampal Formation ◽

Brain Mri ◽

Imaging Biomarkers ◽

Clinical Dementia Rating

ABSTRACTBackground: Population-based studies face challenges in measuring brain structure relative to cognitive aging. We examined the feasibility of acquiring state-of-the-art brain MRI images at a community hospital, and attempted to cross-validate two independent approaches to image analysis.Methods: Participants were 49 older adults (29 cognitively normal and 20 with mild cognitive impairment (MCI)) drawn from an ongoing cohort study, with annual clinical assessments within one month of scan, without overt cerebrovascular disease, and without dementia (Clinical Dementia Rating (CDR) < 1). Brain MRI images, acquired at the local hospital using the Alzheimer's Disease Neuroimaging Initiative protocol, were analyzed using (1) a visual atrophy rating scale and (2) a semi-automated voxel-level morphometric method. Atrophy and volume measures were examined in relation to cognitive classification (any MCI and amnestic MCI vs. normal cognition), CDR (0.5 vs. 0), and presumed etiology.Results: Measures indicating greater atrophy or lesser volume of the hippocampal formation, the medial temporal lobe, and the dilation of the ventricular space were significantly associated with cognitive classification, CDR = 0.5, and presumed neurodegenerative etiology, independent of the image analytic method. Statistically significant correlations were also found between the visual ratings of medial temporal lobe atrophy and the semi-automated ratings of brain structural integrity.Conclusions: High quality MRI data can be acquired and analyzed from older adults in population studies, enhancing their capacity to examine imaging biomarkers in relation to cognitive aging and dementia.

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Visuospatial memory and learning in first-episode schizophreniform psychosis and established schizophrenia: a functional correlate of hippocampal pathology?

Psychological Medicine ◽

10.1017/s0033291702005275 ◽

2002 ◽

Vol 32 (3) ◽

pp. 429-438 ◽

Cited By ~ 61

Author(s):

S. J. WOOD ◽

T. PROFFITT ◽

K. MAHONY ◽

D. J. SMITH ◽

J.-A. BUCHANAN ◽

...

Keyword(s):

Recognition Memory ◽

Associative Learning ◽

Temporal Lobe ◽

Medial Temporal Lobe ◽

Spatial Working Memory ◽

Learning Ability ◽

First Episode ◽

Visuospatial Memory ◽

Learning Test ◽

The Right

Background. Despite a number of studies that have indicated impaired memory function in patients with schizophrenia, there have been few that have used a sensitive measure of right medial temporal lobe pathology. Given the reported findings of reduced hippocampal volume in schizophrenia, we used a theoretically sensitive test of the right medial temporal lobe to determine the nature of the visuospatial memory deficit in the disorder.Methods. Seventy-six patients (37 with a first-episode schizophreniform psychosis, and 39 with established schizophrenia) were compared with 41 comparison subjects on a number of tests of visuospatial memory. These included spatial working memory, spatial and pattern recognition memory and a pattern-location associative learning test.Results. Both patient groups displayed recognition memory deficits when compared to the comparison group. However, only those patients with established schizophrenia (of 9 years duration on average) were impaired on the associative learning test.Conclusions. The results indicate either a progressive decline in visuospatial associative learning ability over the course of the disorder, or that poor visuospatial associative learning is a marker for poor prognosis. In addition, these results have implications for our understanding of the role of the right medial temporal lobe in the pathophysiology of schizophrenia.

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