scholarly journals Postmortem neurodegenerative markers and trajectories of decline in cognitive systems

Neurology ◽  
2019 ◽  
Vol 92 (8) ◽  
pp. e831-e840 ◽  
Author(s):  
Robert S. Wilson ◽  
Jingyun Yang ◽  
Lei Yu ◽  
Sue E. Leurgans ◽  
Ana W. Capuano ◽  
...  

ObjectiveTo assess whether neurodegenerative pathologies are differentially related to trajectories of change in different cognitive abilities.MethodsAt annual intervals for up to 21 years, 915 older participants in a longitudinal clinical-pathologic cohort study completed a battery of 15 tests from which previously established composite measures of episodic memory, semantic memory, working memory, and perceptual speed were derived. At death, they underwent a neuropathologic examination to quantify Alzheimer disease pathology, Lewy bodies, transactive response DNA-binding protein 43 (TDP-43) pathology, and hippocampal sclerosis plus multiple markers of cerebrovascular disease. Time-varying effect models were used to assess change over time in the relation of neuropathologic markers to cognitive trajectories.ResultsControlling for pathology, decline in perceptual speed was evident about 15 years before death; modest decline in semantic and working memory occurred later; and there was little change in episodic memory. Each neurodegenerative marker was associated with lower episodic memory function beginning about 10 to 16 years before death. As time before death decreased, Alzheimer disease pathology, Lewy bodies, and hippocampal sclerosis were associated with impairment in other cognitive domains but the association of TDP-43 pathology with cognition continued to be mainly confined to episodic memory.ConclusionsThe results suggest that episodic memory impairment is an early sign of multiple neurodegenerative conditions, which primarily differ in their associations with other cognitive systems.

2009 ◽  
Vol 15 (4) ◽  
pp. 536-546 ◽  
Author(s):  
PABLO CAMPO ◽  
FERNANDO MAESTÚ ◽  
IRENE GARCÍA-MORALES ◽  
ANTONIO GIL-NAGEL ◽  
BRYAN STRANGE ◽  
...  

AbstractIt has been traditionally assumed that medial temporal lobe (MTL) is not required for working memory (WM). However, animal lesion and electrophysiological studies and human neuropsychological and neuroimaging studies have provided increasing evidences of a critical involvement of MTL in WM. Based on previous findings, the central aim of this study was to investigate the contribution of the MTL to verbal WM encoding. Here, we used magnetoencephalography (MEG) to compare the patterns of MTL activation of 9 epilepsy patients suffering from left hippocampal sclerosis with those of 10 healthy matched controls while they performed a verbal WM task. MEG recordings allow detailed tracking of the time course of MTL activation. We observed impaired WM performance associated with changes in the dynamics of MTL activity in epilepsy patients. Specifically, whereas patients showed decreased activity in damaged MTL, activity in the contralateral MTL was enhanced, an effect that became significant in the 600- to 700-ms interval after stimulus presentation. These findings strongly support the crucial contribution of MTL to verbal WM encoding and provide compelling evidence for the proposal that MTL contributes to both episodic memory and WM. Whether this pattern is signaling reorganization or a normal use of a damaged structure is discussed. (JINS, 2009, 15, 536–546.)


2016 ◽  
Author(s):  
Shea J. Andrews ◽  
Debjani Das ◽  
Kaarin J. Anstey ◽  
Simon Easteal

AbstractGenetic factors make a substantial contribution to inter-individual variability in cognitive function. A recent meta-analysis of genome-wide association studies identified two loci, AKAP6 and MIR2113 that are associated with general cognitive function. Here, we extend this previous research by investigating the association of MIR2113 and AKAP6 with baseline and longitudinal nonlinear change across a broad spectrum of cognitive domains in community-based cohort of 1,570 older adults without dementia. Two SNPs, MIR211-rs10457441 and AKAP6-rs17522122 were genotyped in 1,570 non-demented older Australians of European ancestry, who were examined up to 4 times over 12 years. Linear mixed effects models were used to examine the association between AKAP6 and MIR2113 with cognitive performance in episodic memory, working memory, vocabulary, perceptual speed and reaction time at baseline and with linear and quadratic rates of change. AKAP6-rs17522122*T was associated with worse baseline performance in episodic memory, working memory, vocabulary and perceptual speed, but it was not associated with cognitive change in any domain. MIR2113-rs10457441*T was associated with accelerated decline in episodic memory. No other associations with baseline cognitive performance or with linear or quadratic rate or cognitive changes was observed for this SNP. These results confirm the previous finding that, AKAP6 is associated with performance across multiple cognitive domains at baseline but not with cognitive decline, while MIR2113 primarily affects the rate at which memory declines over time.


2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 98-98
Author(s):  
Corinne Cannavale ◽  
Caitlyn Edwards ◽  
Ruyu Liu ◽  
Samantha Iwinski ◽  
Anne Walk ◽  
...  

Abstract Objectives Carotenoids are plant pigments known to deposit in neural tissues including the hippocampus, a brain substrate that supports several memory forms. However, there is a dearth of knowledge regarding carotenoid status and working memory function in children. Accordingly, this study aimed to understand the relationship between macular and skin carotenoids to visual and auditory working memory (WM) function. Methods Seventy preadolescent children (7–12 years, 32 males) were recruited from the East-Central Illinois area. Auditory working memory was assessed using the story recall subtest of the Woodcock-Johnson IV Test of Cognitive Abilities. A subsample (N = 61, 27 males) completed a visual working memory task and reaction time was quantified to determine speed of memory processing at set sizes of 1 to 4 items. Macular pigment optical density (MPOD) was assessed using customized heterochromatic flicker photometry. Skin carotenoids were assessed using reflection spectroscopy (Veggie Meter). Hierarchical linear regressions were conducted to assess the relationship between carotenoid status and WM function, while controlling for age, sex, income, and whole-body % fat (DXA). Results Auditory WM was positively associated with skin carotenoids (b = 0.263, P = 0.039) but not MPOD (b = −0.044, P = 0.380). In contrast, MPOD was significantly associated with faster visual WM speed at set size 3 (b = −0.253, P = 0.039) and trending at set sizes of 1 (b = −0.225, P = 0.051), 2 (b = −0.171, P = 0.121), and 4 (b = −0.230, P = 0.055). Interestingly, skin carotenoids were not related to visual WM performance at either set size (all P’s > 0.300). Conclusions These results indicate that auditory and visual WM may be differentially related to carotenoids. While skin carotenoids encompass all carotenoids consumed in diet, lutein and zeaxanthin are the only carotenoids which deposit in the macula. Given that MPOD was only related to visual WM, this suggests lutein plays a larger role in these neural functions relative to auditory WM. Interestingly, MPOD's relationship with visual WM increased in strength with the more difficult trial type (i.e., increasing set size), indicating MPOD is related at higher levels of WM capacity. Funding Sources This study was funded by the Egg Nutrition Center.


2019 ◽  
Author(s):  
Kelly J. Murphy ◽  
Travis E. Hodges ◽  
Paul A.S. Sheppard ◽  
Angela K. Troyer ◽  
Elizabeth Hampson ◽  
...  

AbstractObjectiveOlder adults with amnestic mild cognitive impairment (aMCI) develop Alzheimer’s type dementia approximately ten times faster annually than the normal population. Adrenal hormones are associated with aging and cognition. We investigated the relationship between acute stress, cortisol, and memory function in aMCI with an exploratory analysis of sex.MethodSalivary cortisol was sampled diurnally and during two test sessions, one session with the Trier Social Stress Test (TSST), to explore differences in the relationship between cortisol and memory function in age-normal cognition (NA) and aMCI. Participants with aMCI (n=6 women, 9 men; mean age=75) or similarly aged NA (n=9 women, 7 men, mean age=75) were given tests of episodic, associative, and spatial working memory with a psychosocial stressor (TSST) in the second session.ResultsThe aMCI group performed worse on the memory tests than NA as expected, and males with aMCI had elevated cortisol levels on test days. Immediate episodic memory was enhanced by social stress in NA but not in the aMCI group, indicating that stress-induced alterations in memory are different in individuals with aMCI. High cortisol was associated with impaired performance on episodic memory in aMCI males only. Cortisol in Session 1 moderated the relationship with spatial working memory, whereby higher cortisol was associated with worse performance in NA, but better spatial working memory in aMCI. In addition, effects of aMCI on perceived anxiety in response to stress exposure were moderated by stress-induced cortisol in a sex-specific manner.ConclusionsWe show effects of aMCI on Test Session cortisol levels and effects on perceived anxiety, and stress-induced impairments in memory in males with aMCI in our exploratory sample. Future studies should explore sex as a biological variable as our findings suggests that effects at the confluence of aMCI and stress can be obfuscated without sex as a consideration.


Author(s):  
J.S. Shaw ◽  
S.M.H. Hosseini

Findings that the brain is capable of plasticity up until old age have led to interest in the use of cognitive training as a potential intervention to delay the onset of dementia. However, individuals participating in training regimens differ greatly with respect to their outcomes, demonstrating the importance of considering individual differences, in particular age and baseline performance in a cognitive domain, when evaluating the effectiveness of cognitive training. In this review, we summarize existing literature on cognitive training in adults across the domains of episodic memory, working memory and the task-switching component of executive functioning to clarify the picture on the impact of age and baseline performance on cognitive training-related improvements. Studies targeting episodic memory induced greater improvements in younger adults with more intact cognitive abilities, explained in part by factors specific to episodic memory training. By contrast, older, lower baseline performance adults improved most in several studies targeting working memory in older individuals as well as in the majority of studies targeting executive functioning, suggesting the preservation of neural plasticity in these domains until very old age. Our findings can have important implications for informing the design of future interventions for enhancing cognitive functions in individuals at the prodromal stage of Alzheimer’s Disease and potentially delaying the clinical onset of Alzheimer’s Disease. Future research should more clearly stratify individuals according to their baseline cognitive abilities and assign specialized, skill-specific cognitive training regimens in order to directly answer the question of how individual differences impact training effectiveness.


Author(s):  
Anne Dorothée Roesch ◽  
Ute Gschwandtner ◽  
Ivana Handabaka ◽  
Antonia Meyer ◽  
Ethan Taub ◽  
...  

<b><i>Objective:</i></b> The objective of this study is to compare 2 different rhythmic, high-intensive interventions, that is, rhythmic speech-language therapy (rSLT) versus rhythmic balance-mobility training (rBMT), against a no-therapy (NT) condition in patients with Parkinson’s disease and against healthy controls (HCs) with regard to the change in or enhancement of cognitive abilities. <b><i>Methods:</i></b> The 4 groups (rSLT: <i>N</i> = 16; rBMT: <i>N</i> = 10; NT: <i>N</i> = 18; and HC: <i>N</i> = 17) were matched for age, sex, and educational level and were tested in 6 cognitive domains: working memory, executive function, visuo-construction, episodic memory, attention, and word retrieval. Assessments took place at baseline, at 4 weeks (T1), and at 6 months (T2). Rhythmic interventions were provided 3 times per week for 4 weeks in total. To analyze true intervention effects between groups and across time, statistical analyses included <i>reliable change index.</i> Intergroup differences were assessed with multivariate assessment of variance, while differences within groups were assessed with 95% confidence intervals of mean difference. <b><i>Results:</i></b> The rSLT improved <i>working memory</i> and <i>word retrieval</i> (<i>p</i> &#x3c; 0.05), possibly a beneficial transfer effect of the training method per se. In contrast, the NT group worsened in <i>phonemic</i> and <i>semantic shifting</i> (<i>p</i> &#x3c; 0.01). Observed improvements in <i>flexibility</i> and in <i>episodic memory</i> in the HC may be linked to training effects of retesting. <b><i>Conclusions:</i></b> Rhythmic cues are resistant to neurodegeneration and have a strong motivating factor. As thus, these may facilitate high-intensive and demanding training. Although both trainings were superior to NT, the improvement of cognitive abilities depends on the specific training method. Further, therapy may be more effective when delivered by a therapist rather than by an impersonal computer program.


2021 ◽  
Vol 72 (1) ◽  
pp. 151-179 ◽  
Author(s):  
Qi Wang

Human memory, as a product of the mind and brain, is inherently private and personal. Yet, arising from the interaction between the organism and its ecology in the course of phylogeny and ontogeny, human memory is also profoundly collective and cultural. In this review, I discuss the cultural foundation of human memory. I start by briefly reflecting on the conception of memory against a historical and cultural background. I then detail a model of a culturally saturated mnemonic system in which cultural elements constitute and condition various processes of remembering, focusing on memory representation, perceptual encoding, memory function, memory reconstruction, memory expression, and memory socialization. Then I discuss research on working memory, episodic memory, and autobiographical memory as examples that further demonstrate how cultural elements shape the processes and consequences of remembering and lay the foundation for human memory. I conclude by outlining some important future directions in memory research.


2020 ◽  
Vol 105 (4) ◽  
pp. e1093-e1105 ◽  
Author(s):  
Rasa Kazlauskaite ◽  
Imke Janssen ◽  
Robert S Wilson ◽  
Bradley M Appelhans ◽  
Denis A Evans ◽  
...  

Abstract Context Metabolic syndrome (MetS) affects cognitive function in late life, particularly in women. But longitudinal research is scarce on associations of MetS with cognitive function during midlife. Objective To determine associations between MetS exposure and cognitive function trajectories in midlife women. Design and Setting This is a 17-year prospective, longitudinal study of multiracial/ethnic women in 7 US communities, with annual/biennial assessments. Participants Participants were 2149 US women traversing menopause. Exposure Exposure consisted of MetS assessments (median 4 assessments over 4 years). Main Outcome Measures Main outcome measures were assessments of cognitive function in 3 domains: perceptual speed (symbol digit modalities test, SDMT), episodic memory (East Boston Memory Test, EBMT), and working memory (Digit Span Backward Test, DSB). Results By their first cognitive assessment (age 50.7 ± 2.9 years), 29.5% met the criteria for MetS. Women completed a median (interquartile range [IQR]) of 6 (IQR 4–7) follow-up cognitive assessments over 11.2 (IQR 9.2–11.5) years. Women with MetS, compared with those without, had a larger 10-year decline in SDMT z-score (estimate –0.087, 95% confidence interval, –0.150 to –0.024; P = 0.007), after adjustment for cognitive testing practice effects, sociodemographics, lifestyle, mood, and menopause factors. As such, MetS accelerated the 10-year loss of perceptual speed by 24%. MetS did not differentially affect the rate of decline in either immediate (P = 0.534) or delayed (P = 0.740) episodic memory or in working memory (P = 0.584). Conclusions In midlife women MetS exposure was associated with accelerated decline in perceptual speed, but not episodic or working memory.


Sign in / Sign up

Export Citation Format

Share Document