P4-059: Hippocampal microstructure and memory performance in Alzheimer's disease: A 7-Tesla MRI study

Hippocampal dysfunction and deficits in episodic memory have been reported for both Alzheimer’s disease (AD) and major depressive disorder (MDD). Primacy performance has been associated with hippocampus-dependent episodic memory, while recency may reflect working memory performance. In this study, serial position profiles were examined in a total of 73 patients with MDD, AD, both AD and MDD, and healthy controls (HC) by means of CERAD-NP word list memory. Primacy performance was most impaired in AD with comorbid MDD, followed by AD, MDD, and HC. Recency performance, on the other hand, was comparable across groups. These findings indicate that primacy in AD is impaired in the presence of comorbid MDD, suggesting additive performance decrements in this specific episodic memory function.

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The role of decreased cortical thickness and volume of medial temporal lobe structures in predicting incident psychosis in patients with Alzheimer's disease: a prospective longitudinal MRI study

American Journal of Geriatric Psychiatry ◽

10.1016/j.jagp.2021.04.015 ◽

2021 ◽

Author(s):

Young-Min Lee ◽

Je-Min Park ◽

Byung-Dae Lee ◽

Eunsoo Moon ◽

Hee-Jeong Jeong ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Temporal Lobe ◽

Cortical Thickness ◽

Medial Temporal Lobe ◽

Longitudinal Mri ◽

Mri Study ◽

Prospective Longitudinal

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Torpor enhances synaptic strength and restores memory performance in a mouse model of Alzheimer’s disease

Scientific Reports ◽

10.1038/s41598-021-94992-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Christina F. de Veij Mestdagh ◽

Jaap A. Timmerman ◽

Frank Koopmans ◽

Iryna Paliukhovich ◽

Suzanne S. M. Miedema ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Mouse Model ◽

Memory Performance ◽

Long Term Potentiation ◽

Fear Memory ◽

Contextual Fear ◽

Contextual Fear Memory ◽

Model Of Alzheimer’S Disease ◽

Term Potentiation

AbstractHibernation induces neurodegeneration-like changes in the brain, which are completely reversed upon arousal. Hibernation-induced plasticity may therefore be of great relevance for the treatment of neurodegenerative diseases, but remains largely unexplored. Here we show that a single torpor and arousal sequence in mice does not induce dendrite retraction and synapse loss as observed in seasonal hibernators. Instead, it increases hippocampal long-term potentiation and contextual fear memory. This is accompanied by increased levels of key postsynaptic proteins and mitochondrial complex I and IV proteins, indicating mitochondrial reactivation and enhanced synaptic plasticity upon arousal. Interestingly, a single torpor and arousal sequence was also sufficient to restore contextual fear memory in an APP/PS1 mouse model of Alzheimer’s disease. Our study demonstrates that torpor in mice evokes an exceptional state of hippocampal plasticity and that naturally occurring plasticity mechanisms during torpor provide an opportunity to identify unique druggable targets for the treatment of cognitive impairment.

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Subjective Cognitive Decline and its Relation to Verbal Memory and Sex in Cognitively Unimpaired Individuals from a Colombian Cohort with Autosomal-Dominant Alzheimer’s Disease

Journal of the International Neuropsychological Society ◽

10.1017/s1355617721000801 ◽

2021 ◽

pp. 1-9

Author(s):

Jairo E. Martinez ◽

Enmanuelle Pardilla-Delgado ◽

Edmarie Guzmán-Vélez ◽

Clara Vila-Castelar ◽

Rebecca Amariglio ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Sex Differences ◽

Cognitive Decline ◽

Verbal Memory ◽

Autosomal Dominant ◽

Memory Performance ◽

Subjective Cognitive Decline ◽

Mutation Carriers ◽

Study Partner

Abstract Objective: Subjective Cognitive Decline (SCD) may be an early indicator of risk for Alzheimer’s disease (AD). Findings regarding sex differences in SCD are inconsistent. Studying sex differences in SCD within cognitively unimpaired individuals with autosomal-dominant AD (ADAD), who will develop dementia, may inform sex-related SCD variations in preclinical AD. We examined sex differences in SCD within cognitively unimpaired mutation carriers from the world’s largest ADAD kindred and sex differences in the relationship between SCD and memory performance. Methods: We included 310 cognitively unimpaired Presenilin-1 (PSEN-1) E280A mutation carriers (51% females) and 1998 noncarrier family members (56% females) in the study. Subjects and their study partners completed SCD questionnaires and the CERAD word list delayed recall test. ANCOVAs were conducted to examine group differences in SCD, sex, and memory performance. In carriers, partial correlations were used to examine associations between SCD and memory performance covarying for education. Results: Females in both groups had greater self-reported and study partner-reported SCD than males (all p < 0.001). In female mutation carriers, greater self-reported (p = 0.02) and study partner-reported SCD (p < 0.001) were associated with worse verbal memory. In male mutation carriers, greater self-reported (p = 0.03), but not study partner-reported SCD (p = 0.11) was associated with worse verbal memory. Conclusions: Study partner-reported SCD may be a stronger indicator of memory decline in females versus males in individuals at risk for developing dementia. Future studies with independent samples and preclinical trials should consider sex differences when recruiting based on SCD criteria.

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Spatial inhibition of return is impaired in mild cognitive impairment and mild Alzheimer’s disease

10.1101/2020.05.11.089383 ◽

2020 ◽

Author(s):

Xiong Jiang ◽

James H. Howard ◽

G. Wiliam Rebeck ◽

R. Scott Turner

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Medial Temporal Lobe ◽

Inhibition Of Return ◽

Memory Performance ◽

Brain Regions ◽

List Type ◽

Older Individuals

ABSTRACTSpatial inhibition of return (IOR) refers to the phenomenon by which individuals are slower to respond to stimuli appearing at a previously cued location compared to un-cued locations. Here we provide evidence supporting that spatial IOR is mildly impaired in individuals with mild cognitive impairment (MCI) or mild Alzheimer’s disease (AD), and the impairment is readily detectable using a novel double cue paradigm. Furthermore, reduced spatial IOR in high-risk healthy older individuals is associated with reduced memory and other neurocognitive task performance, suggesting that the novel double cue spatial IOR paradigm may be useful in detecting MCI and early AD.SIGNIFICANCE STATEMENTNovel double cue spatial inhibition of return (IOR) paradigm revealed a robust effect IOR deficits in individuals with mild cognitive impairment (MCI) or mild Alzheimer’s disease (AD)Spatial IOR effect correlates with memory performance in healthy older adults at a elevated risk of Alzheimer’s disease (with a family history or APOE e4 allele)The data suggests that double cue spatial IOR may be sensitive to detect early AD pathological changes, which may be linked to disease progress at the posterior brain regions (rather than the medial temporal lobe)

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