Structural and Metabolic Correlates of Episodic Memory in Relation to the Depth of Encoding in Normal Aging

2009 ◽  
Vol 21 (2) ◽  
pp. 372-389 ◽  
Author(s):  
Grégoria Kalpouzos ◽  
Gaël Chételat ◽  
Brigitte Landeau ◽  
Patrice Clochon ◽  
Fausto Viader ◽  
...  
Keyword(s):  
Retention Interval ◽  
Episodic Memory ◽  
Gray Matter Volume ◽  
Memory Task ◽  
The Elderly ◽  
Structural Mri ◽  
Normal Aging ◽  
Elderly Subjects ◽  
Middle Aged ◽  
The One

This study set out to establish the relationship between changes in episodic memory retrieval in normal aging on the one hand and gray matter volume and 18FDG uptake on the other. Structural MRI, resting-state 18FDG-PET, and an episodic memory task manipulating the depth of encoding and the retention interval were administered to 46 healthy subjects divided into three groups according to their age (young, middle-aged, and elderly adults). Memory decline was found not to be linear in the course of normal aging: Whatever the retention interval, the retrieval of shallowly encoded words was impaired in both the middle-aged and the elderly, whereas the retrieval of deeply encoded words only declined in the elderly. In middle-aged and elderly subjects, the reduced performance in the shallow encoding condition was mainly related to posterior mediotemporal volume and metabolism. By contrast, the impaired retrieval of deeply encoded words in the elderly group was mainly related to frontal and parietal regions, suggesting the adoption of inefficient strategic processes.

scholarly journals Effects of amnesia on processing in the hippocampus and default mode network during a naturalistic memory task: a case study

2018 ◽  
Author(s):  
Christiane Oedekoven ◽  
James L. Keidel ◽  
Stuart Anderson ◽  
Angus Nisbet ◽  
Chris Bird
Keyword(s):  
Functional Connectivity ◽  
Episodic Memory ◽  
Memory Performance ◽  
Memory Task ◽  
Structural Mri ◽  
Brain Regions ◽  
Left Hippocampus ◽  
Cortical Regions ◽  
The Right ◽  
Encoding And Retrieval

Despite their severely impaired episodic memory, individuals with amnesia are able to comprehend ongoing events. Online representations of a current event are thought to be supported by a network of regions centred on the posterior midline cortex (PMC). By contrast, episodic memory is widely believed to be supported by interactions between the hippocampus and these cortical regions. In this MRI study, we investigated the encoding and retrieval of lifelike events (video clips) in a patient with severe amnesia likely resulting from a stroke to the right thalamus, and a group of 20 age-matched controls. Structural MRI revealed grey matter reductions in left hippocampus and left thalamus in comparison to controls. We first characterised the regions activated in the controls while they watched and retrieved the videos. There were no differences in activation between the patient and controls in any of the regions. We then identified a widespread network of brain regions, including the hippocampus, that were functionally connected with the PMC in controls. However, in the patient there was a specific reduction in functional connectivity between the PMC and a region of left hippocampus when both watching and attempting to retrieve the videos. A follow up analysis revealed that in controls the functional connectivity between these regions when watching the videos was correlated with memory performance. Taken together, these findings support the view that the interactions between the PMC and the hippocampus enable the encoding and retrieval of multimodal representations of the contents of an event.

Changes in processing adverbial conjuncts throughout adulthood

1996 ◽  
Vol 17 (1) ◽  
pp. 105-116
Author(s):  
Ronald L. Bloom ◽  
Jeanne Mullin ◽  
Peter J. Paternostro
Keyword(s):  
Life Span ◽  
The Elderly ◽  
Education Level ◽  
Significant Decline ◽  
Elderly Subjects ◽  
Linguistic Processing ◽  
Middle Aged ◽  
Age Related ◽  
Processing Abilities

ABSTRACTThis study examines the use and understanding of concordant (e.g., consequently, moreover) and discordant (e.g., rather, contrastively) adverbial conjuncts in the later part of the life span. The participants, 75 neurologically healthy young (mean age 21.8), middle-aged (mean age 51.7), and elderly (mean age 73.1) adults, were examined using procedures by Nippold, Schwarz, and Undlin (1992). Groups were matched for education level. The results indicate a significant decline in processing adverbial conjuncts in the elderly. Discordant adverbial conjuncts especially challenged the linguistic processing abilities of the elderly subjects. The age- related decline in processing adverbial conjuncts.appears to be a specific deficit in linguistic processing that is independent of problems in memory or the effects of exposure to sophisticated language forms.

scholarly journals Sleep and Aging: Endocrine and Epigenetic Aspects

2020 ◽  
Vol 6 (8) ◽  
pp. 65-96
Author(s):  
S. Bulgakova ◽  
N. Romanchuk
Keyword(s):  
Significant Contribution ◽  
Human Life ◽  
The Elderly ◽  
Normal Aging ◽  
Epigenetic Factors ◽  
Network Interaction ◽  
Age Related ◽  
Falling Asleep ◽  
Slow Sleep ◽  
The One

Along with many physiological changes during normal aging, sleep also changes. Age-related changes in sleep include: a decrease in the duration of night sleep, an increase in the frequency of falling asleep during the day, an increase in the number of night awakenings and time spent without sleep during the night, a decrease in the phase of slow sleep, etc. Most of these changes occur between the young and the middle and remain unchanged in the elderly. In addition, the circadian system and homeostatic sleep mechanisms become less stable with aging. The level and nature of the secretion of hormones acting on sleep change during normal aging, which affects the processes of sleep and wakefulness. Sleep indicators are interrelated and/or dependent on lifestyle, polymorbidity (somatic, psychological), polypharmacy, epigenetic (social, economic, environmental, etc.) factors. Increased average human life expectancy and neuroendocrine changes in physiological and pathological aging, on the one hand, epigenetic factors and electromagnetic information load/overload, on the other hand, made a significant contribution to the circadian nature of human brain neural network interaction with artificial intelligence.

scholarly journals VH3 Antibody Response to Immunization with Pneumococcal Polysaccharide Vaccine in Middle-Aged and Elderly Persons

2011 ◽  
Vol 18 (3) ◽  
pp. 362-366 ◽  
Author(s):  
Jose A. Serpa ◽  
Josemon Valayam ◽  
Daniel M. Musher ◽  
Roger D. Rossen ◽  
Liise-anne Pirofski ◽  
...  
Keyword(s):  
The Elderly ◽  
Polysaccharide Vaccine ◽  
Antibody Responses ◽  
Elderly Subjects ◽  
Enzyme Linked Immunosorbent Assay ◽  
Elderly Persons ◽  
Pneumococcal Polysaccharide Vaccine ◽  
Elderly Adults ◽  
Middle Aged ◽  
Idiotypic Antibody

ABSTRACTPneumococcal disease continues to cause substantial morbidity and mortality among the elderly. Older adults may have high levels of anticapsular antibody after vaccination, but their antibodies show decreased functional activity. In addition, the protective effect of the pneumococcal polysaccharide vaccine (PPV) seems to cease as early as 3 to 5 years postvaccination. Recently, it was suggested that PPV elicits human antibodies that use predominantly VH3 gene segments and induce a repertoire shift with increased VH3 expression in peripheral B cells. Here we compared VH3-idiotypic antibody responses in middle-aged and elderly subjects receiving PPV as initial immunization or revaccination. We studied pre- and postvaccination sera from 36 (18 vaccine-naïve and 18 previously immunized subjects) middle-aged and 40 (22 vaccine-naïve and 18 previously immunized subjects) elderly adults who received 23-valent PPV. Concentrations of IgGs to four individual serotypes (6B, 14, 19F, and 23F) and of VH3-idiotypic antibodies (detected by the monoclonal antibody D12) to the whole pneumococcal vaccine were determined by enzyme-linked immunosorbent assay (ELISA). PPV elicited significant IgG and VH3-idiotypic antibody responses in middle-aged and elderly subjects, regardless of whether they were vaccine naïve or undergoing revaccination. Age did not influence the magnitude of the antibody responses, as evidenced by similar postvaccination IgG and VH3 antibody levels in both groups, even after stratifying by prior vaccine status. Furthermore, we found similar proportions (around 50%) of elderly and middle-aged subjects experiencing 2-fold increases in VH3 antibody titers after vaccination. Age or repeated immunization does not appear to affect the VH3-idiotypic immunogenicity of PPV among middle-aged and elderly adults.

Differences in EEG Harmonic Driving Responses to Photic Stimulation between Normal Aging and Alzheimer's Disease

2002 ◽  
Vol 33 (2) ◽  
pp. 86-92 ◽  
Author(s):  
Mitsuru Kikuchi ◽  
Yuji Wada ◽  
Yoshifumi Koshino
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Functional Organization ◽  
Brain Activation ◽  
The Elderly ◽  
Normal Aging ◽  
Photic Stimulation ◽  
Elderly Subjects ◽  
Absolute Power ◽  
The Brain

In order to investigate whether Alzheimer's disease (AD) is the end result of aging of the brain or the result of some other mechanism, we analyzed EEGs showing the absolute power of harmonic responses to photic stimulation (PS) in younger subjects, non-demented elderly subjects and AD patients. At rest, the AD patients generally showed less absolute power than the younger and elderly subjects, with significant differences found at 10Hz and 20Hz. Analysis of EEGs recorded during PS indicated that the elderly subjects generally demonstrated more absolute power than the younger subjects and AD patients. These findings suggest a failure of stimulation-related brain activation in AD patients, and provide further evidence that normal aging and AD employ different mechanisms for functional organization during PS.

Pyridostigmine partially restores the GH responsiveness to GHRH in normal aging

1990 ◽  
Vol 123 (2) ◽  
pp. 169-173 ◽  
Author(s):  
E. Ghigo ◽  
S. Goffi ◽  
E. Arvat ◽  
M. Nicolosi ◽  
M. Procopio ◽  
...  
Keyword(s):  
Normal Subjects ◽  
The Elderly ◽  
Normal Aging ◽  
Elderly Subjects ◽  
Plasma Growth Hormone ◽  
Gh Secretion ◽  
Combined Administration ◽  
Basal Plasma ◽  
Young Subjects ◽  
Plasma Gh

Abstract. In 11 elderly normal subjects and in 17 young healthy subjects we studied the response of plasma growth hormone to GH-releasing hormone (GHRH(29), 1 μg/kg iv) alone and preceded by pyridostigmine ( 120 mg orally 60 min before GHRH), a cholinesterase inhibitor likely able to suppress somatostatin release. The GH response to pyridostigmine alone was also examined. Basal plasma GH levels were similar in elderly and young subjects. In the elderly, GHRH induced a GH rise (AUC, median and range: 207.5, 43.5-444.0 μg · 1−1 · h−1) which was lower (p = 0.006) than that observed in young subjects (548.0, 112.5-2313.5 μg · 1−1 · h−1). The pyridostigmine-induced GH rise in the elderly was similar to that in young subjects (300.5, 163.0-470.0 vs 265.0, 33.0-514.5 μg · 1−1 · h−1). Pyridostigmine potentiated the GH responsiveness to GHRH in both elderly (437.5, 152.0-1815.5 μg · 1−1 · h−1; p = 0.01 vs GHRH alone) and young subjects (2140.0, 681.5-4429.5 μg · 1−1 · h−1; p = 0.0001 vs GHRH alone). However, the GH response to pyridostigmine + GHRH was significantly lower (p = 0.0001) in elderly than in young subjects. In conclusion, the cholinergic enhancement by pyridostigmine is able to potentiate the blunted GH response to GHRH in elderly subjects, inducing a GH increase similar to that observed after GHRH alone in young adults. This finding suggests that an alteration of somatostatinergic tone could be involved in the reduced GH secretion in normal aging. However, a decreased GH response to combined administration of pyridostigmine and GHRH in elderly subjects suggests that other abnormalities may coexist, leading to the secretory hypoactivity of somatotropes.

scholarly journals Lower regional gray matter volume in the absence of higher cortical amyloid burden in late-life depression

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Akihiro Takamiya ◽  
Thomas Vande Casteele ◽  
Michel Koole ◽  
François-Laurent De Winter ◽  
Filip Bouckaert ◽  
...  
Keyword(s):  
Episodic Memory ◽  
Gray Matter ◽  
Memory Function ◽  
Gray Matter Volume ◽  
Verbal Learning ◽  
Late Life ◽  
Amyloid Deposition ◽  
Elderly Subjects ◽  
Late Life Depression ◽  
Matter Volume

AbstractLate-life depression (LLD) is associated with a risk of developing Alzheimer’s disease (AD). However, the role of AD-pathophysiology in LLD, and its association with clinical symptoms and cognitive function are elusive. In this study, one hundred subjects underwent amyloid positron emission tomography (PET) imaging with [18F]-flutemetamol and structural MRI: 48 severely depressed elderly subjects (age 74.1 ± 7.5 years, 33 female) and 52 age-/gender-matched healthy controls (72.4 ± 6.4 years, 37 female). The Geriatric Depression Scale (GDS) and Rey Auditory Verbal Learning Test (RAVLT) were used to assess the severity of depressive symptoms and episodic memory function respectively. Amyloid deposition was quantified using the standardized uptake value ratio. Whole-brain voxel-wise comparisons of amyloid deposition and gray matter volume (GMV) between LLD and controls were performed. Multivariate analysis of covariance was conducted to investigate the association of regional differences in amyloid deposition and GMV with clinical factors, including GDS and RAVLT. As a result, there were no significant group differences in amyloid deposition. In contrast, LLD showed significant lower GMV in the left temporal and parietal region. GMV reduction in the left temporal region was associated with episodic memory dysfunction, but not with depression severity. Regional GMV reduction was not associated with amyloid deposition. LLD is associated with lower GMV in regions that overlap with AD-pathophysiology, and which are associated with episodic memory function. The lack of corresponding associations with amyloid suggests that lower GMV driven by non-amyloid pathology may play a central role in the neurobiology of LLD presenting as a psychiatric disorder.Trial registration: European Union Drug Regulating Authorities Clinical Trials identifier: EudraCT 2009-018064-95.

scholarly journals The Importance of Physical Activity in the Interaction of Motor and Cognitive Functions in Elderly People

2020 ◽  
Vol 3 (118) ◽  
pp. 13-18
Author(s):  
Vida Janina Česnaitienė ◽  
Zbigniew Ossowski ◽  
Diana Karanauskienė ◽  
Gabrielė Auškalnyte ◽  
Ema Grigėnaitytė ◽  
...  
Keyword(s):  
Physical Activity ◽  
Elderly People ◽  
Cognitive Functions ◽  
Memory Task ◽  
The Elderly ◽  
Elderly Subjects ◽  
Research Subjects ◽  
Physically Active ◽  
Eyes Closed ◽  
Significant Difference

Background. It is predicted that in 2060, the number of elderly people in Lithuania (62 and over years of age) will be 31.2% (Tamutienė & Naujanienė, 2013). The maintenance of stable posture requires particular attention because it gets more difficult to sustain it while doing multiple moves at the same time when you are getting older (Woo, Davids, Liukkonen, Chow, & Jaakkola, 2017). The aim of the study was to determine the importance of physical activity for the interplay of motor and cognitive functions in elderly people. Methods. Evaluation of static equilibrium by posturographic method, evaluation of cognitive functions, statistical analysis. Results. The results of the physically active and inactive research subjects were statistically significant (p = .043) in memory task with the eyes closed and in a simple position. A statistically significant difference in the sway velocity (Vsc) between the physical activity groups with eyes closed in simple position was also observed (p = .044). Double task with eyes closed resulted in worse balance performance. Conclusions. 1. Physical activity did not affect the motor function of the elderly. There were no differences between the physically active and inactive subjects in the assessed behavioral indices. 2. Physical activity did not affect the cognitive functions of the elderly. All elderly subjects were equally mistaken in their cognitive memory task. 3. The motor functions of the physically active elderly are controlled statistically significantly better when performing additional cognitive tasks than those of the physically inactive ones. Keywords: balance, elderly, physical activity.

scholarly journals A robust deep neural network for denoising task-based fMRI data: An application to working memory and episodic memory

2019 ◽  
Author(s):  
Zhengshi Yang ◽  
Xiaowei Zhuang ◽  
Karthik Sreenivasan ◽  
Virendra Mishra ◽  
Tim Curran ◽  
...  
Keyword(s):  
Neural Network ◽  
Working Memory ◽  
Episodic Memory ◽  
Gray Matter ◽  
Deep Neural Network ◽  
Memory Task ◽  
Fmri Data ◽  
Elderly Subjects ◽  
Fully Connected ◽  
Time Point

ABSTRACTIn this study, a deep neural network (DNN) is proposed to reduce the noise in task-based fMRI data without explicitly modeling noise. The DNN artificial neural network consists of one temporal convolutional layer, one long short-term memory (LSTM) layer, one time-distributed fully-connected layer, and one unconventional selection layer in sequential order. The LSTM layer takes not only the current time point but also what was perceived in a previous time point as its input to characterize the temporal autocorrelation of fMRI data. The fully-connected layer weights the output of the LSTM layer, and the output denoised fMRI time series is selected by the selection layer. Assuming that task-related neural response is limited to gray matter, the model parameters in the DNN network are optimized by maximizing the correlation difference between gray matter voxels and white matter or ventricular cerebrospinal fluid voxels. Instead of targeting a particular noise source, the proposed neural network takes advantage of the task design matrix to better extract task-related signal in fMRI data. The DNN network, along with other traditional denoising techniques, has been applied on simulated data, working memory task fMRI data acquired from a cohort of healthy subjects and episodic memory task fMRI data acquired from a small set of healthy elderly subjects. Qualitative and quantitative measurements were used to evaluate the performance of different denoising techniques. In the simulation, DNN improves fMRI activation detection and also adapts to varying hemodynamic response functions across different brain regions. DNN efficiently reduces physiological noise and generates more homogeneous task-response correlation maps in real data.

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