Influence of visual stimuli on spatial navigation and memory of MCI, Alzheimer's disease patients and healthy control subjects

ABSTRACTBackground: The purpose of the present study was to gain insight into Alzheimer's disease (AD) patients’ perception of the world through the study of a few aspects of awareness. The aspects in focus of the study were disease awareness, metacognition, managing of everyday life, and as a complement, the agreement (calibration) between patients and their spouses on the studied aspects was considered.Method: A mixed-method evaluation design was used involving 15 AD patients, their spouses, and 15 elderly healthy control subjects. The study comprised both a semistructured interview (AD patients and spouse) and a neuropsychological assessment (AD patients and control subjects).Results: The patients were aware of their disease and able to report on their illness. Despite this awareness, they were unable to realize and manage the practical and cognitive implications of their impairment. The results also indicate that patients and spouses were not well calibrated regarding thoughts about the disease and problems in handling the cognitive deterioration.Conclusions: The findings of our study have relevance to patients’ well being and how they manage everyday life. An open dialogue on these issues between spouses and in the care for AD patients would hopefully enhance quality of life for all parties involved.

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Alteredβ-Amyloid Precursor Protein Isoforms in Mexican Alzheimer’s Disease Patients

Disease Markers ◽

10.1155/2006/347502 ◽

2006 ◽

Vol 22 (3) ◽

pp. 119-125 ◽

Cited By ~ 1

Author(s):

V. J. Sánchez-González ◽

G. G. Ortiz ◽

P. Gallegos-Arreola ◽

M. A. Macías-Islas ◽

E. D. Arias-Merino ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Risk Factor ◽

Amyloid Precursor Protein ◽

Precursor Protein ◽

Protein Isoforms ◽

Control Subjects ◽

High Risk Factor ◽

Healthy Control ◽

App Ratio

Objective: To determine theβ-amyloid precursor protein (βAPP) isoforms ratio as a risk factor for Alzheimer’s Disease and to assess its relationship with demographic and genetic variables of the disease.Methods: Blood samples from 26 patients fulfilling NINCDS-ADRDA diagnostic criteria for AD and 46 healthy control subjects were collected for Western blotting forβAPP. A ratio ofβAPP isoforms, in optical densities, between the upper band (130 Kd) and the lower bands (106–110 Kd) was obtained. Odds ratios were obtained to determine risk factor of this component.Results:βAPP ratio on AD subjects was lower than that of control subjects: 0.3662 ± 0.1891 vs. 0.6769 ± 0.1021 (mean ± SD, p<0.05). A lowβAPP ratio (<0.6) showed an OR of 4.63 (95% CI 1.45 ± 15.33). When onset of disease was taken into account, aβAPP ratio on EOAD subjects of 0.3965 ± 0.1916 was found vs. 0.3445 ± 0.1965 on LOAD subjects (p>0.05).Conclusions: AlteredβAPP isoforms is a high risk factor for Alzheimer’s disease, although it has no influence on the time of onset of the disease.

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Nonlinear analysis of electroencephalogram and magnetoencephalogram recordings in patients with Alzheimer's disease

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2008.0197 ◽

2008 ◽

Vol 367 (1887) ◽

pp. 317-336 ◽

Cited By ~ 116

Author(s):

Roberto Hornero ◽

Daniel Abásolo ◽

Javier Escudero ◽

Carlos Gómez

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Nonlinear Analysis ◽

Approximate Entropy ◽

Multiscale Entropy ◽

Nonlinear Methods ◽

Control Subjects ◽

Healthy Control ◽

And Control ◽

Electroencephalogram Eeg

The aim of the present study is to show the usefulness of nonlinear methods to analyse the electroencephalogram (EEG) and magnetoencephalogram (MEG) in patients with Alzheimer's disease (AD). The following nonlinear methods have been applied to study the EEG and MEG background activity in AD patients and control subjects: approximate entropy, sample entropy, multiscale entropy, auto-mutual information and Lempel–Ziv complexity. We discuss why these nonlinear methods are appropriate to analyse the EEG and MEG. Furthermore, the performance of all these methods has been compared when applied to the same databases of EEG and MEG recordings. Our results show that EEG and MEG background activities in AD patients are less complex and more regular than in healthy control subjects. In line with previous studies, our work suggests that nonlinear analysis techniques could be useful in AD diagnosis.

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Are visual cues helpful for virtual spatial navigation and spatial memory in patients with mild cognitive impairment or Alzheimer’s disease?

Neuropsychology ◽

10.1037/neu0000435 ◽

2018 ◽

Vol 32 (4) ◽

pp. 385-400 ◽

Cited By ~ 9

Author(s):

Mélanie Cogné ◽

Sophie Auriacombe ◽

Louise Vasa ◽

François Tison ◽

Evelyne Klinger ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Spatial Memory ◽

Visual Cues ◽

Spatial Navigation ◽

Navigation And Spatial Memory

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Validation of the Hungarian version of Alzheimer’s Disease Assessment Scale – Cognitive Subscale

Orvosi Hetilap ◽

10.1556/oh.2012.29332 ◽

2012 ◽

Vol 153 (12) ◽

pp. 461-466 ◽

Cited By ~ 5

Author(s):

Magdolna Pákáski ◽

Gergely Drótos ◽

Zoltán Janka ◽

János Kálmán

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Mental State ◽

Mini Mental State Examination ◽

Assessment Scale ◽

Disease Assessment ◽

Control Subjects ◽

Cognitive Subscale ◽

State Examination ◽

Hungarian Version

The cognitive subscale of the Alzheimer’s Disease Assessment Scale is the most widely used test in the diagnostic and research work of Alzheimer’s disease. Aims: The aim of this study was to validate and investigate reliability of the Hungarian version of the Alzheimer’s Disease Assessment Scale in patients with Alzheimer’s disease and healthy control subjects. Methods: syxty-six patients with mild and moderate Alzheimer’s disease and 47 non-demented control subjects were recruited for the study. The cognitive status was established by the Hungarian version of the Alzheimer’s Disease Assessment Scale and Mini Mental State Examination. Discriminative validity, the relation between age and education and Alzheimer’s Disease Assessment Scale, and the sensitivity and specificity of the test were determined. Results: Both the Mini Mental State Examination and the Alzheimer’s Disease Assessment Scale had significant potential in differentiating between patients with mild and moderate stages of Alzheimer’s disease and control subjects. A very strong negative correlation was established between the scores of the Mini Mental State Examination and the Alzheimer’s Disease Assessment Scale in the Alzheimer’s disease group. The Alzheimer’s Disease Assessment Scale showed slightly negative relationship between education and cognitive performance, whereas a positive correlation between age and Alzheimer’s Disease Assessment Scale scores was detected only in the control group. According to the analysis of the ROC curve, the values of sensitivity and specificity of the Alzheimer’s Disease Assessment Scale were high. Conclusions: The Hungarian version of the Alzheimer’s Disease Assessment Scale was found to be highly reliable and valid and, therefore, the application of this scale can be recommended for the establishment of the clinical stage and follow-up of patients with Alzheimer’s disease. However, the current Hungarian version of the Alzheimer’s Disease Assessment Scale is not sufficient; the list of words and linguistic elements should be selected according to the Hungarian standard in the future. Orv. Hetil., 2012, 153, 461–466.

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Subjective Spatial Navigation Complaints - A Frequent Symptom Reported by Patients with Subjective Cognitive Decline, Mild Cognitive Impairment and Alzheimer's Disease

Current Alzheimer Research ◽

10.2174/1567205014666171120145349 ◽

2018 ◽

Vol 15 (3) ◽

pp. 219-228 ◽

Cited By ~ 6

Author(s):

Jiri Cerman ◽

Ross Andel ◽

Jan Laczo ◽

Martin Vyhnalek ◽

Zuzana Nedelska ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Cognitive Impairment ◽

Mild Cognitive Impairment ◽

Cognitive Decline ◽

Spatial Navigation ◽

Subjective Cognitive Decline ◽

Great Effort ◽

Frequent Symptom ◽

Normal Controls

Background: Great effort has been put into developing simple and feasible tools capable to detect Alzheimer's disease (AD) in its early clinical stage. Spatial navigation impairment occurs very early in AD and is detectable even in the stage of mild cognitive impairment (MCI). Objective: The aim was to describe the frequency of self-reported spatial navigation complaints in patients with subjective cognitive decline (SCD), amnestic and non-amnestic MCI (aMCI, naMCI) and AD dementia and to assess whether a simple questionnaire based on these complaints may be used to detect early AD. Method: In total 184 subjects: patients with aMCI (n=61), naMCI (n=27), SCD (n=63), dementia due to AD (n=20) and normal controls (n=13) were recruited. The subjects underwent neuropsychological examination and were administered a questionnaire addressing spatial navigation complaints. Responses to the 15 items questionnaire were scaled into four categories (no, minor, moderate and major complaints). Results: 55% of patients with aMCI, 64% with naMCI, 68% with SCD and 72% with AD complained about their spatial navigation. 38-61% of these complaints were moderate or major. Only 33% normal controls expressed complaints and none was ranked as moderate or major. The SCD, aMCI and AD dementia patients were more likely to express complaints than normal controls (p's<0.050) after adjusting for age, education, sex, depressive symptoms (OR for SCD=4.00, aMCI=3.90, AD dementia=7.02) or anxiety (OR for SCD=3.59, aMCI=3.64, AD dementia=6.41). Conclusion: Spatial navigation complaints are a frequent symptom not only in AD, but also in SCD and aMCI and can potentially be detected by a simple and inexpensive questionnaire.

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Structural Changes in Thalamic Nuclei Across Prodromal and Clinical Alzheimer’s Disease

Journal of Alzheimer s Disease ◽

10.3233/jad-201583 ◽

2021 ◽

pp. 1-11

Author(s):

Adam S. Bernstein ◽

Steven Z. Rapcsak ◽

Michael Hornberger ◽

Manojkumar Saranathan ◽

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Large Scale ◽

Structural Changes ◽

Thalamic Nuclei ◽

Medial Temporal Lobes ◽

Cognitive Changes ◽

Temporal Lobes ◽

Medial Geniculate ◽

Healthy Control

Background: Increasing evidence suggests that thalamic nuclei may atrophy in Alzheimer’s disease (AD). We hypothesized that there will be significant atrophy of limbic thalamic nuclei associated with declining memory and cognition across the AD continuum. Objective: The objective of this work was to characterize volume differences in thalamic nuclei in subjects with early and late mild cognitive impairment (MCI) as well as AD when compared to healthy control (HC) subjects using a novel MRI-based thalamic segmentation technique (THOMAS). Methods: MPRAGE data from the ADNI database were used in this study (n = 540). Healthy control (n = 125), early MCI (n = 212), late MCI (n = 114), and AD subjects (n = 89) were selected, and their MRI data were parcellated to determine the volumes of 11 thalamic nuclei for each subject. Volumes across the different clinical subgroups were compared using ANCOVA. Results: There were significant differences in thalamic nuclei volumes between HC, late MCI, and AD subjects. The anteroventral, mediodorsal, pulvinar, medial geniculate, and centromedian nuclei were significantly smaller in subjects with late MCI and AD when compared to HC subjects. Furthermore, the mediodorsal, pulvinar, and medial geniculate nuclei were significantly smaller in early MCI when compared to HC subjects. Conclusion: This work highlights nucleus specific atrophy within the thalamus in subjects with early and late MCI and AD. This is consistent with the hypothesis that memory and cognitive changes in AD are mediated by damage to a large-scale integrated neural network that extends beyond the medial temporal lobes.

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