scholarly journals Storage and Processing Working Memory Functions in Alzheimer-Type Dementia

1999 ◽  
Vol 11 (4) ◽  
pp. 227-231 ◽  
Author(s):  
T. Vecchi ◽  
V. Saveriano ◽  
L. Paciaroni
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Working Memory ◽  
Control Group ◽  
Alzheimer Type ◽  
Memory Functions ◽  
Early Stages ◽  
Alzheimer Type Dementia ◽  
Age Related ◽  
Active Processes

A selective deterioration of working memory functions has been suggested as an explanation of the cognitive decay occurring in normal ageing as well as in Alzheimer-type dementia. Recent studies have highlighted that elderly people’s limitations in working memory functions may be better interpreted when analysing the specific characteristics of the cognitive process (i.e., passive storage or active manipulation of information). In the present study, we have adapted a procedure used to investigate age-related memory modifications, involving both verbal and visuo-spatial material in tasks tapping passive and active processes, to investigate the deterioration associated with Alzheimer's disease. A group of Alzheimer patients in the early stages of the disease were matched to a control group of healthy elderly. Results show that Alzheimer patients performed less accurately than the control group in all tasks. However, the deficit was maximised in the case of active processes, regardless of the type of material used (verbal or visuo-spatial). These data highlight the importance of considering the amount of active processing as the key variable when interpreting the decay in cognitive functions in the early stages of Alzheimer’s disease.

Preclinical Cognitive Trajectories Differ for Alzheimer's Disease and Vascular Dementia

2012 ◽  
Vol 18 (2) ◽  
pp. 191-199 ◽  
Author(s):  
Erika J. Laukka ◽  
Stuart W.S. MacDonald ◽  
Laura Fratiglioni ◽  
Lars Bäckman
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Vascular Dementia ◽  
Early Stage ◽  
Block Design ◽  
Word Recall ◽  
Cognitive Tasks ◽  
Control Group ◽  
Age Related ◽  
Preclinical Ad

AbstractWe investigated differences between Alzheimer's disease (AD) and vascular dementia (VaD) from the appearance of the first cognitive symptoms, focusing on both time of onset and rate of accelerated decline for different cognitive functions before dementia diagnosis. Data from a longitudinal population-based study were used, including 914 participants (mean age = 82.0 years, SD = 5.0) tested with a cognitive battery (word recall and recognition, Block Design, category fluency, clock reading) on up to four occasions spanning 10 years. We fit a series of linear mixed effects models with a change point to the cognitive data, contrasting each dementia group to a control group. Significant age-related decline was observed for all five cognitive tasks. Relative to time of diagnosis, the preclinical AD persons deviated from the normal aging curve earlier (up to 9 years) compared to the preclinical VaD persons (up to 6 years). However, once the preclinical VaD persons started to decline, they deteriorated at a faster rate than the preclinical AD persons. The results have important implications for identifying the two dementia disorders at an early stage and for selecting cognitive tasks to evaluate treatment effects for persons at risk of developing AD and VaD. (JINS, 2012, 18, 191–199)

scholarly journals Emotional Working Memory and Alzheimer’s Disease

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Nicola Mammarella ◽  
Beth Fairfield
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Working Memory ◽  
Memory Performance ◽  
Memory Task ◽  
Emotional Information ◽  
Healthy Older Adults ◽  
Affective Stimuli ◽  
Age Related ◽  
Dementia Of Alzheimer’S Type

A number of recent studies have reported that working memory does not seem to show typical age-related deficits in healthy older adults when emotional information is involved. Differently, studies about the short-term ability to encode and actively manipulate emotional information in dementia of Alzheimer’s type are few and have yielded mixed results. Here, we review behavioural and neuroimaging evidence that points to a complex interaction between emotion modulation and working memory in Alzheimer’s. In fact, depending on the function involved, patients may or may not show an emotional benefit in their working memory performance. In addition, this benefit is not always clearly biased (e.g., towards negative or positive information). We interpret this complex pattern of results as a consequence of the interaction between multiple factors including the severity of Alzheimer’s disease, the nature of affective stimuli, and type of working memory task.

scholarly journals Nutritional status of selenium in Alzheimer's disease patients

2009 ◽  
Vol 103 (6) ◽  
pp. 803-806 ◽  
Author(s):  
Bárbara Rita Cardoso ◽  
Thomas Prates Ong ◽  
Wilson Jacob-Filho ◽  
Omar Jaluul ◽  
Maria Isabel d'Ávila Freitas ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Nutritional Status ◽  
Neuronal Degeneration ◽  
Hydride Generation ◽  
Control Group ◽  
Food Record ◽  
Age Related ◽  
Normal Cognitive Function ◽  
Dietary Food

Studies have shown that various antioxidants are decreased in different age-related degenerative diseases and thus, oxidative stress would have a central role in the pathogenesis of many disorders that involve neuronal degeneration, including Alzheimer's disease (AD). The present study aimed to assess the nutritional status of Se in AD patients and to compare with control subjects with normal cognitive function. The case–control study was carried out on a group of elderly with AD (n 28) and compared with a control group (n 29), both aged between 60 and 89 years. Se intake was evaluated by using a 3-d dietary food record. Se was evaluated in plasma, erythrocytes and nails by using the method of hydride generation atomic absorption spectroscopy. Deficient Se intake was largely observed in the AD group. AD patients showed significantly lower Se levels in plasma, erythrocytes and nails (32·59 μg/l, 43·74 μg/l and 0·302 μg/g) when compared with the control group (50·99 μg/l, 79·16 μg/l and 0·400 μg/g). The results allowed us to suggest that AD has an important relation with Se deficiency.

scholarly journals Effect of cortisol levels on working memory performance in elderly subjects with Alzheimer's disease

2008 ◽  
Vol 66 (3b) ◽  
pp. 619-624 ◽  
Author(s):  
Juliana Nery de Souza-Talarico ◽  
Paulo Caramelli ◽  
Ricardo Nitrini ◽  
Eliane Corrêa Chaves
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Working Memory ◽  
Digit Span ◽  
Memory Performance ◽  
Elderly Subjects ◽  
Control Group ◽  
Acute Administration ◽  
Healthy Elderly ◽  
Cortisol Levels

BACKGROUND: Subjects with Alzheimer's disease (AD) have elevated cortisol levels as a result of hypothalamic-pituitary-adrenal (HPA) axis dysfunction. Acute administration of hydrocortisone has been associated with working memory (WM) performance in young adults. OBJECTIVE: To investigate whether cortisol levels are associated with WM performance in subjects with AD. METHOD: Eighty subjects were included, comprising 40 patients with mild AD and 40 healthy elderly controls. WM was assessed using the Digit Span Backward test (DSB). Saliva samples were collected to determine cortisol levels. RESULTS: AD subjects had poorer performance on the DSB than controls (p=0.002) and also presented higher levels of cortisol than control group (p=0.04). No significant correlation was observed between the DSB and cortisol levels in both groups (r= -0.29). CONCLUSION: In this study, elevated cortisol levels were not associated with poorer WM performance in patients with AD or in healthy elderly subjects.

scholarly journals Predicting Alzheimer’s disease progression trajectory and clinical subtypes using machine learning

2019 ◽  
Author(s):  
Vipul K. Satone ◽  
Rachneet Kaur ◽  
Anant Dadu ◽  
Hampton Leonard ◽  
Hirotaka Iwaki ◽  
...  
Keyword(s):  
Machine Learning ◽  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Disease Progression ◽  
Disease Onset ◽  
Machine Learning Techniques ◽  
Progression Rate ◽  
Early Stages ◽  
Age Related ◽  
Learning Techniques

AbstractBackgroundAlzheimer’s disease (AD) is a common, age-related, neurodegenerative disease that impairs a person’s ability to perform day-to-day activities. Diagnosing AD is challenging, especially in the early stages. Many patients still go undiagnosed, partly due to the complex heterogeneity in disease progression. This highlights a need for early prediction of the disease course to assist its treatment and tailor therapy options to the disease progression rate. Recent developments in machine learning techniques provide the potential to not only predict disease progression and trajectory of AD but also to classify the disease into different etiological subtypes.Methods and findingsThe work shown here clusters participants in distinct and multifaceted progression subgroups of AD and discusses an approach to predict the progression rate from baseline diagnosis. We observed that the myriad of clinically reported symptoms summarized in the proposed AD progression space corresponds directly with memory and cognitive measures, which are routinely used to monitor disease onset and progression. Our analysis demonstrated accurate prediction of disease progression after four years from the first 12 months of post-diagnosis clinical data (Area Under the Curve of 0.96 (95% confidence interval (CI), 0.92-1.0), 0.81 (95% CI, 0.74-0.88) and 0.98 (95% CI, 0.96-1.0) for slow, moderate and fast progression rate patients respectively). Further, we explored the long short-term memory (LSTM) neural networks to predict the trajectory of an individual patient’s progression.ConclusionThe machine learning techniques presented in this study may assist providers in identifying different progression rates and trajectories in the early stages of the disease, hence allowing for more efficient and personalized healthcare deliveries. With additional information about the progression rate of AD at hand, providers may further individualize the treatment plans. The predictive tests discussed in this study not only allow for early AD diagnosis but also facilitate the characterization of distinct AD subtypes relating to trajectories of disease progression. These findings are a crucial step forward for early disease detection. These models can be used to design improved clinical trials for AD research.

scholarly journals Frontal Functional Connectivity Impairment in Early Stages of Alzheimer’s Disease

2021 ◽  
Author(s):  
Ivan Plaza-Rosales ◽  
Rodrigo Montefusco-Siegmund ◽  
Samuel Madariaga ◽  
Enzo Brunetti ◽  
María Isabel Behrens ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Functional Connectivity ◽  
Long Range ◽  
Brain Activity ◽  
Spatial Navigation ◽  
Visual Exploration ◽  
Control Group ◽  
Beta Band ◽  
Early Stages

Abstract Background Many neurophysiological markers such as neuronal oscillations, cortical neuronal synchronization and long-range neuronal coupling have been suggested to permit the identification of early cognitive impairments in Alzheimer's disease (AD). However, it is still unclear whether alterations in long-range Functional Connectivity (FC) constitute part of early mechanisms in the initial stages of AD.MethodsEighteen participants (69-88 years old), classified as early AD and matching healthy controls, were evaluated while performing a virtual spatial navigation task. We combined electroencephalography (EEG) and eye movement recordings during the performance of a virtual version of the Morris Water Maze (VMWM), where participants had to find a submerged, invisible platform. The groups were compared in their navigation performance with different metrics of brain activity.ResultsWe found that the subjects of both groups showed characteristic visual exploration patterns, with a central and over the horizontal midline exploration in controls and more peripheral and sparse fixations, in early AD subjects. In addition, regions in visual exploration between the groups were significantly different. The control group presented a marked occipital activity in the beta band (15-20 Hz) in comparison to the early AD group at early processing time. These differences in the beta band were much more robust in prefrontal regions with significant differences in the frontal cortex, which has been associated with spatial navigation tasks in addition to planning and decision making.ConclusionsThese results suggest that long-range Functional connectivity networks generated from early visual activity contribute to the mechanisms involved in the loss of spatial encoding at the early stages of AD.

scholarly journals Effects of Swimming Training and Royal Jelly on BDNF and NGF Gene Expression in Hippocampus Tissue of Rats with Alzheimer’s Disease

2020 ◽  
Vol 22 (2) ◽  
Author(s):  
Amin Dehbozorgi ◽  
Laleh Behbudi Tabrizi ◽  
Seyed Ali Hosseini ◽  
Masod Haj Rasoli
Keyword(s):  
Gene Expression ◽  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Royal Jelly ◽  
Neurodegenerative Disorder ◽  
Control Group ◽  
Swimming Training ◽  
Age Related ◽  
And Training ◽  
Ngf Gene

Background: Alzheimer’s disease (AD) is an age-related neurodegenerative disorder. Evidence from neuropathological studies indicates that the levels of neurotrophins brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) are compromised in AD. Objectives: The present study aimed to review the effects of swimming training and royal jelly (RJ) on BDNF and NGF gene expression in the hippocampus tissue of rats with AD. Methods: In the present experimental study, 25 rats with AD were divided into five groups, including (1) control, (2) sham, (3) RJ, (4) training, and (5) training with RJ. Five healthy rats were selected as the healthy control group to examine the effect of AD induction by 8 mg/kg trimethyltin chloride (TMT) intra-peritoneally on BDNF and NGF. During eight weeks, groups 3 and 5 received 100 mg/kg RJ daily intra-peritoneally, and groups 4 and 5 swam in a rat swimming tank three sessions per week. One-way ANOVA with Tukey’s post hoc test was used for data analysis in SPSS 20 software (P < 0.05). Results: The induction of AD by TMT had a significant effect on the reduction of BDNF (P = 0.001) and NGF (P = 0.001). However, RJ had a significant effect on the increase of NGF (P = 0.03). Nevertheless, RJ (P = 0.99), training (P = 0.99), and training with RJ (P = 0.94) had no significant effect on BDNF and training (P = 0.99) and training with RJ (P = 0.97) had no significant effect on NGF. Conclusions: It appears that RJ has a significant effect on the increase of NGF gene expression in the hippocampus tissue of rats with AD. Nevertheless, RJ consumption simultaneously with swimming training has no significant effect on BDNF and NGF.

scholarly journals The role of impairment of higher mental functions in suicidogenesis in the dementia caused by Alzheimer's disease

2018 ◽  
Vol 3 (3) ◽  
pp. e0303104
Author(s):  
Iryna Mudrenko
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
High Risk ◽  
Suicidal Behavior ◽  
Control Group ◽  
Elderly Age ◽  
Mental Functions ◽  
Age Related ◽  
Higher Mental Functions

Background Dementia is the age-related disease. At the same time, the elderly age has one of the peaks in the number of suicides. Psychology of patients with demetia is characterized by the feeling of hopelessness, pessimism, awareness of own insolvency, dependence on others, that affects the risk of suicide. It is established that the highest risk of suicide in the early stages of dementia with the progression of cognitive deficit, the risk of suicide decreases. Aim To study the role of impairment of higher mental functions (perception, reasoning, attention, memory, emotions, will, speech) in the formation of suicidal behaviour in patients with dementia in Alzheimer's disease. Materials and methods There were examined 75 patients with dementia in Alzheimer's disease, 36 patients with a history of suicidal behavior composed the main group, and 39 patients without the signs of suicidal behavior composed control group. The study was carried out using clinical-anamnestic, psychopathological methods and mathematical statistical methods. Results The high risk of suicide in dementia caused by Alzheimer's disease is combined with the inhibition of thinking, the delusional ideas of self-blame and self-effacement (p ≤ 0.05); depressed mood, inner agitation, anxiety, feeling of despair, hopelessness, guilt, melancholia, apathy (p ≤ 0.05); effector-volitional disorders in the form of hypobulia, hypokinesia, hypomimia, decreased libido (p ≤ 0.05); speech disturbance in the form of bradylalia p ≤ 0.05; greater exhaustion and decreased attention (p ≤ 0.05). On the contrary, the following peculiarities of higher mental functions, namely thought disorder are referred to the anti-risk factors of suicide in dementia caused by Alzheimer's disease: the delusional ideas of relation and damage (p ≤ 0.05); emotions: the feeling of fear (p ≤ 0.05); effector-volitional sphere: parabulia and hyperkinesia (p ≤ 0.05). Conclusion On the basis of clinical and psychopathological study of patients with dementia in Alzheimer's disease, the specific impairment of higher mental functions and emotional-volitional spheres reasoning, memory, attention, perception, speech, emotions) are identified associated with high risk of suicide.

scholarly journals Brain connectivity during Alzheimer’s disease progression and its cognitive impact in a transgenic rat model

2020 ◽  
Vol 4 (2) ◽  
pp. 397-415
Author(s):  
Emma Muñoz-Moreno ◽  
Raúl Tudela ◽  
Xavier López-Gil ◽  
Guadalupe Soria
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Transgenic Animals ◽  
Brain Network ◽  
Control Group ◽  
Transgenic Rat ◽  
Disease Evolution ◽  
Early Stages ◽  
Graph Metrics ◽  
New Treatments

The research of Alzheimer’s disease (AD) in its early stages and its progression till symptomatic onset is essential to understand the pathology and investigate new treatments. Animal models provide a helpful approach to this research, since they allow for controlled follow-up during the disease evolution. In this work, transgenic TgF344-AD rats were longitudinally evaluated starting at 6 months of age. Every 3 months, cognitive abilities were assessed by a memory-related task and magnetic resonance imaging (MRI) was acquired. Structural and functional brain networks were estimated and characterized by graph metrics to identify differences between the groups in connectivity, its evolution with age, and its influence on cognition. Structural networks of transgenic animals were altered since the earliest stage. Likewise, aging significantly affected network metrics in TgF344-AD, but not in the control group. In addition, while the structural brain network influenced cognitive outcome in transgenic animals, functional network impacted how control subjects performed. TgF344-AD brain network alterations were present from very early stages, difficult to identify in clinical research. Likewise, the characterization of aging in these animals, involving structural network reorganization and its effects on cognition, opens a window to evaluate new treatments for the disease.

scholarly journals A REVIEW ON “NEW TREATMENT STRATEGIES FOR ALZHEIMER’S DISEASE AS NEURODEGENERATIVE DISEASE AND ITS RISK FACTOR CAUSE, SYMPTOMS, AND TREATMENT AT WORLDWIDE”

2016 ◽  
Vol 9 (9) ◽  
pp. 16
Author(s):  
Rohit Jaysing Bhor
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Working Memory ◽  
Risk Factor ◽  
Social Life ◽  
Disease Risk ◽  
Treatment Strategies ◽  
Disease Diagnosis ◽  
Age Related ◽  
Antidementia Drugs

ABSTRACTAlzheimer’s disease (AD) is a dynamic and irreversible neurodegenerative illness and relates to the most widely recognized reason for dementiaaround the world. AD is a dynamic and lethal cerebrum ailment. Alzheimer’s obliterates mind cells, bringing on memory issue or misfortune and issueswith speculation and conduct sufficiently serious to influence work, long lasting leisure activities or social life. Alzheimer’s illness is quickly becomingworldwide, but there is no cure for it. Now, accessible medications just give symptomatic help and do not mediate in infection prepare adequatelyenough to avert or cure it. Various late studies have reported that working memory does not appear to demonstrate regular age-related deficienciesin solid more established grown-ups when enthusiastic data are included. Indeed, contingent upon the capacity included, patients might demonstratean enthusiastic advantage in their working memory execution. Moreover, this advantage is not generally obviously one-sided (e.g., toward negativeor positive data). We decipher this intricate example of results as an outcome of the cooperation between numerous components including theseriousness of AD, the nature of emotional jolts, and sort of working memory errand. Clinical advantages of the accessible pharmacological treatmentfor AD with antidementia drugs (to be specific cholinesterase inhibitors and Memantine) are obvious. In an unexpected way, learns about the transientcapacity to encode and effectively control enthusiastic data in dementia of Alzheimer’s sort are few and have yielded blended results.Keywords: Alzheimer’s disease, Risk factor for Alzheimer’s disease, Diagnosis, Classification of Anti-Alzheimer’s drug.

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