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

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.

GeroPsych ◽  
2012 ◽  
Vol 25 (4) ◽  
pp. 235-245 ◽  
Author(s):  
Katja Franke ◽  
Christian Gaser

We recently proposed a novel method that aggregates the multidimensional aging pattern across the brain to a single value. This method proved to provide stable and reliable estimates of brain aging – even across different scanners. While investigating longitudinal changes in BrainAGE in about 400 elderly subjects, we discovered that patients with Alzheimer’s disease and subjects who had converted to AD within 3 years showed accelerated brain atrophy by +6 years at baseline. An additional increase in BrainAGE accumulated to a score of about +9 years during follow-up. Accelerated brain aging was related to prospective cognitive decline and disease severity. In conclusion, the BrainAGE framework indicates discrepancies in brain aging and could thus serve as an indicator for cognitive functioning in the future.


Neurosignals ◽  
1996 ◽  
Vol 5 (6) ◽  
pp. 343-348 ◽  
Author(s):  
Wei Ping Li ◽  
Helen W.L. Lai ◽  
Suet Ying Cheng ◽  
David T. Yew

2021 ◽  
Vol 20 ◽  
Author(s):  
Choy Ker Woon ◽  
Wong Kah Hui ◽  
Razif Abas ◽  
Muhammad Huzaimi Haron ◽  
Srijit Das ◽  
...  

: Alzheimer's disease (AD) affects the elderly and is characterized by progressive neurodegeneration caused by different pathologies. The most significant challenges in treating AD include the inability of medications to reach the brain because of its poor solubility, low bioavailability, and the presence of the blood-brain barrier (BBB). Additionally, current evidence suggests the disruption of BBB plays an important role in the pathogenesis of AD. One of the critical challenges in treating AD is the ineffective treatments and its severe adverse effects. Nanotechnology offers an alternative approach to facilitate the treatment of AD by overcoming the challenges in drug transport across the BBB. Various nanoparticles (NP) loaded with natural products were reported to aid in drug delivery for the treatment of AD. The nano- sized entities of NP are great platforms for incorporating active materials from natural products into formulations that can be delivered effectively to the intended action site without compromising the material’s bioactivity. The review highlights the applications of medicinal plants, their derived components, and various nanomedicine-based approaches for the treatment of AD. The combination of medicinal plants and nanotechnology may lead to new theragnostic solutions for the treatment of AD in the future.


2011 ◽  
Vol 5 (2) ◽  
pp. 108-113 ◽  
Author(s):  
Maria Niures P.S. Matioli ◽  
Arnaldo Etzel ◽  
João A.G.G. Prats ◽  
Wares F. de O. Medeiros ◽  
Taiguara R. Monteiro ◽  
...  

Abstract Alzheimer's disease (AD) is the most common cause of dementia in the elderly. Efforts to determine risk factors for the development of AD are important for risk stratification and early diagnosis. Furthermore, there are no standardized practices for memory screening. Lack of knowledge on AD, perception of memory loss as part of normal aging, and poor socioeconomic conditions may also be implicated in the current situation of dementia. Objective: To evaluate knowledge of AD in a literate population of elders and correlate these findings with sociodemographic characteristics. Methods: A descriptive survey design study enrolled 994 volunteers from September 2007 to May 2008 in the city of Santos, São Paulo, Brazil, to answer a brief questionnaire consisting of 8 simple questions about knowledge of AD and worries about memory loss. Results: Greater knowledge about AD was associated with eight or more years of education, female gender and age between 60 and 70 years. Also, 52.8% of responders (95% CI - 49.5-56.0%) answered that memory loss is part of normal aging and 77.5% (95% CI - 74.7-80.1%) had never sought a doctor to evaluate their memories. Conclusion: Our study results reinforced that the first line of preventing late diagnosis of dementia is to act in health promotion, especially by targeting subjects older than 70 years of male gender and with lower educational level. It also provided evidence that strategies to promote physician initiative in treating memory problems are also paramount.


2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Corona Solana ◽  
Raquel Tarazona ◽  
Rafael Solana

Alzheimer’s disease (AD) represents the most common cause of dementia in the elderly. AD is a neurodegenerative disorder characterized by progressive memory loss and cognitive decline. Although the aetiology of AD is not clear, both environmental factors and heritable predisposition may contribute to disease occurrence. In addition, inflammation and immune system alterations have been linked to AD. The prevailing hypothesis as cause of AD is the deposition in the brain of amyloid beta peptides (Aβ). Although Aβ have a role in defending the brain against infections, their accumulation promotes an inflammatory response mediated by microglia and astrocytes. The production of proinflammatory cytokines and other inflammatory mediators such as prostaglandins and complement factors favours the recruitment of peripheral immune cells further promoting neuroinflammation. Age-related inflammation and chronic infection with herpes virus such as cytomegalovirus may also contribute to inflammation in AD patients. Natural killer (NK) cells are innate lymphoid cells involved in host defence against viral infections and tumours. Once activated NK cells secrete cytokines such as IFN-γ and TNF-α and chemokines and exert cytotoxic activity against target cells. In the elderly, changes in NK cell compartment have been described which may contribute to the lower capacity of elderly individuals to respond to pathogens and tumours. Recently, the role of NK cells in the immunopathogenesis of AD is discussed. Although in AD patients the frequency of NK cells is not affected, a high NK cell response to cytokines has been described together with NK cell dysregulation of signalling pathways which is in part involved in this altered behaviour.


2021 ◽  
pp. 1-28
Author(s):  
Sirawit Sriwichaiin ◽  
Nipon Chattipakorn ◽  
Siriporn C. Chattipakorn

Alzheimer’s disease (AD) has become a major health problem among the elderly population. Some evidence suggests that metabolic disturbance possibly plays a role in the pathophysiology of AD. Currently, the study of metabolomics has been used to explore changes in multiple metabolites in several diseases, including AD. Thus, the metabolomics research in AD might provide some information regarding metabolic dysregulations, and their possible associated pathophysiology. This review summarizes the information discovered regarding the metabolites in the brain and the blood from the metabolomics research of AD from both animal and clinical studies. Additionally, the correlation between the changes in metabolites and outcomes, such as pathological findings in the brain and cognitive impairment are discussed. We also deliberate on the findings of cohort studies, demonstrating the alterations in metabolites before changes of cognitive function. All of these findings can be used to inform the potential identity of specific metabolites as possible biomarkers for AD.


2020 ◽  
Author(s):  
Qi Wang ◽  
Siwei Chen ◽  
He Wang ◽  
Luzeng Chen ◽  
Yongan Sun ◽  
...  

AbstractAlzheimer’s disease (AD) is a common neurodegenerative disease in the elderly, early diagnosis and timely treatment are very important to delay the course of the disease. In the past, most of the brain regions related to AD were identified based on the imaging method, which can only identify some atrophic brain regions. In this work, we used mathematical models to find out the potential brain regions related to AD. First, diffusion tensor imaging (DTI) was used to construct the brain structural network. Next, we set a new local feature index 2hop-connectivity to measure the correlation among different areas. And for this, we proposed a novel algorithm named 2hopRWR to measure 2hop-connectivity. At last, we proposed a new index GFS (Global Feature Score) based on global feature by combing 5 local features: degree centrality, betweenness centrality, closeness centrality, the number of maximal cliques, and 2hop-connectivity, to judge which brain regions are likely related to Alzheimer’s Disease. As a result, all the top ten brain regions in GFS scoring difference between the AD group and the non-AD group were related to AD by literature verification. Finally, the results of the canonical correlation analysis showed that the GFS was significantly correlated with the scores of the mini-mental state examination (MMSE) scale and montreal cognitive assessment (MoCA) scale. So, we believe the GFS can also be used as a new index to assist in diagnosis and objective monitoring of disease progression. Besides, the method proposed in this paper can be used as a differential network analysis method in other areas of network analysis.


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