Abstract Dementia, and in particular Alzheimer’s disease (AD), can be characterized by disrupted functional connectivity in the brain caused by beta-amyloid deposition in neural links. ...Non-pharmaceutical treatments for dementia have recently explored interventions involving the stimulation of neuronal populations in the gamma band. These interventions aim to restore brain network functionality by synchronizing rhythmic energy through various stimulation modalities. Entrainment, a newly proposed non-invasive sensory stimulation method, has shown promise in improving cognitive functions in dementia patients. This study investigates the effectiveness of entrainment in terms of promoting neural synchrony and spatial connectivity across the cortex. EEG signals were recorded during a 40 Hz auditory entrainment session conducted with a group of elderly participants with dementia. Phase locking value (PLV) between different intraregional and interregional sites was examined as an attribute of network synchronization, and connectivity of local and distant links were compared during the stimulation and rest trials. Our findings demonstrate enhanced neural synchrony between the frontal and parietal regions, which are key components of the brain’s default mode network (DMN). The DMN operation is known to be impacted by dementia’s progression, leading to reduced functional connectivity across the parieto-frontal pathways. Notably, entrainment alone significantly improves synchrony between these DMN components, suggesting its potential for restoring functional connectivity.
High-frequency oscillations of the frontal cortex are involved in functions of the brain that fuse processed data from different sensory modules or bind them with elements stored in the memory. These ...oscillations also provide inhibitory connections to neural circuits that perform lower-level processes. Deficit in the performance of these oscillations has been examined as a marker for Alzheimer's disease (AD). Additionally, the neurodegenerative processes associated with AD, such as the deposition of amyloid-beta plaques, do not occur in a spatially homogeneous fashion and progress more prominently in the medial temporal lobe in the early stages of the disease. This region of the brain contains neural circuitry involved in olfactory perception. Several studies have suggested that olfactory deficit can be used as a marker for early diagnosis of AD. A quantitative assessment of the performance of the olfactory system can hence serve as a potential biomarker for Alzheimer's disease, offering a relatively convenient and inexpensive diagnosis method. This study examines the decline in the perception of olfactory stimuli and the deficit in the performance of high-frequency frontal oscillations in response to olfactory stimulation as markers for AD. Two measurement modalities are employed for assessing the olfactory performance: 1) An interactive smell identification test is used to sample the response to a sizable variety of odorants, and 2) Electroencephalography data are collected in an olfactory perception task with a pair of selected odorants in order to assess the connectivity of frontal cortex regions. Statistical analysis methods are used to assess the significance of selected features extracted from the recorded modalities as Alzheimer's biomarkers. Olfactory decline regressed to age in both healthy and mild AD groups are evaluated, and single- and multi-modal classifiers are also developed. The novel aspects of this study include: 1) Combining EEG response to olfactory stimulation with behavioral assessment of olfactory perception as a marker of AD, 2) Identification of odorants most significantly affected in mild AD patients, 3) Identification of odorants which are still adequately perceived by mild AD patients, 4) Analysis of the decline in the spatial coherence of different oscillatory bands in response to olfactory stimulation, and 5) Being the first study to quantitatively assess the performance of olfactory decline due to aging and AD in the Iranian population.
Probiotics have been suggested as an effective adjuvant treatment for Alzheimer’s disease (AD) due to their modulating effect on the gut microbiota, which may affect the gut-brain axis. Therefore, we ...aimed to evaluate the effects of two different single-strain probiotics on cognition, physical activity, and anxiety in subjects with mild and moderate AD. Eligible patients (
n
= 90) with AD were randomly assigned to either of two interventions
Lactobacillus rhamnosus
HA-114 (10
15
CFU) or
Bifidobacterium longum
R0175 (10
15
CFU) or placebo group, receiving probiotic supplement twice daily for 12 weeks. The primary outcome of the study was cognitive function measured by using the two tests, namely, the Mini-Mental State Examination (MMSE) and the categorical verbal fluency test (CFT). Secondary outcomes included a performance in Activities of Daily Living (ADL), the Lawton Instrumental Activities of Daily Living (IADL) scale, and the Generalized Anxiety Disorder (GAD-7) scale. Linear mixed-effect models were used to investigate the independent effects of probiotics on clinical outcomes. After 12 weeks, MMSE significantly improved cognition (
P
Interaction
< 0.0001), with
post hoc
comparisons identifying significantly more improvement in the
B. longum
intervention group (differences: 4.86, 95% CI: 3.91–5.81;
P
< 0.0001) compared with both the placebo and
L. rhamnosus
intervention groups (differences: 4.06, 95% CI: 3.11–5.01;
P
< 0.0001). There was no significant difference between the two intervention groups (differences: −0.8, 95% CI: −1.74 to 0.14;
P
= 0.09). In conclusion, this trial demonstrated that 12-week probiotic supplementation compared with placebo had beneficial effects on the cognition status of patients with AD.
An increasing number of studies in Western countries have shown that healthy eating patterns have a protective effect against cognitive decline and dementia, however, information about this ...relationship among non-western populations with different cultural environments is scarce. The present study investigated the association between dietary patterns (DPs) and cognitive function in the Iranian elderly.
In this case-control study, the data of 290 elderly people in two groups of case and control (Mean age in case: 74.2 ± 8.6, in control: 67.3 ± 7.3 year) were analyzed. Two DPs of healthy and unhealthy were extracted from a 142-item dish-based food frequency questionnaire, and patterns driven by principal components analysis (PCA) of 25 food groups. Multivariate binary logistic regression calculated the odds ratio (OR) of cognitive impairment with adjustment for potential confounding factors.
A healthy DP, characterized by high consumption of fruits and vegetables, legumes, and nuts, was related to a decrease in the odds of Alzheimer's disease in Iranian elderly people. Also, moderate adherence to an unhealthy food pattern was associated with an increase in the probability of the disease; however, the association was not statistically significant.
In this elderly population, a healthy eating pattern was associated with reducing the risk of Alzheimer's disease. Further prospective studies are recommended.
Electroencephalography (EEG) has been commonly used to measure brain alterations in Alzheimer's Disease (AD). However, reported changes are limited to those obtained from using univariate measures, ...including activation level and frequency bands. To look beyond the activation level, we used multivariate pattern analysis (MVPA) to extract patterns of information from EEG responses to images in an animacy categorization task. Comparing healthy controls (HC) with patients with mild cognitive impairment (MCI), we found that the neural speed of animacy information processing is decreased in MCI patients. Moreover, we found critical time-points during which the representational pattern of animacy for MCI patients was significantly discriminable from that of HC, while the activation level remained unchanged. Together, these results suggest that the speed and pattern of animacy information processing provide clinically useful information as a potential biomarker for detecting early changes in MCI and AD patients.
This study addresses the challenge of differentiating between bipolar disorder II (BD II) and borderline personality disorder (BPD), which is complicated by overlapping symptoms. To overcome this, a ...multimodal machine learning approach was employed, incorporating both electroencephalography (EEG) patterns and cognitive abnormalities for enhanced classification. Data were collected from 45 participants, including 20 with BD II and 25 with BPD. Analysis involved utilizing EEG signals and cognitive tests, specifically the Wisconsin Card Sorting Test and Integrated Cognitive Assessment. The k-nearest neighbors (KNN) algorithm achieved a balanced accuracy of 93%, with EEG features proving to be crucial, while cognitive features had a lesser impact. Despite the strengths, such as diverse model usage, it’s important to note limitations, including a small sample size and reliance on DSM diagnoses. The study suggests that future research should explore multimodal data integration and employ advanced techniques to improve classification accuracy and gain a better understanding of the neurobiological distinctions between BD II and BPD.
Severe acute respiratory disease is associated with chronic secondary infections that exacerbate symptoms and mortality. So far, many drugs have been introduced to treat this disease, none of which ...effectively control the coronavirus. Numerous studies have shown that mitochondria, as the center of cell biogenesis, are vulnerable to drugs, especially antibiotics. Antibiotics were widely prescribed during the early phase of the pandemic. We performed a literature review to assess the reasons, evidence, and practices on the use of antibiotics in coronavirus disease 2019 (COVID-19) in- and outpatients. The current research found widespread usage of antibiotics, mostly in an empirical context, among COVID-19 hospitalized patients. The effectiveness of this approach has not been established. Given the high death rate linked with secondary infections in COVID-19 patients and the developing antimicrobial resistance, further study is urgently needed to identify the most appropriate rationale for antibiotic therapy in these patients.
Throughout life, mechanisms such as damage and inflammation can alter the permeability of the blood-brain barrier(BBB). According to some studies, increasing the permeability of the blood-brain ...barrier can occur in a time-dependent manner following restraint stress. On the other hand, there have been reports of increased N-Methyl-D-Aspartate Receptor (NMDAR) -Ab seroprevalence in chronic stress conditions. The presence of antibody-secreting cells / memory B cells in the intrathecal area of the brain and their redistribution under various environmental stresses, which can be independent of the BBB status, are other points in this area that can emphasize the role of environmental stress in Anti NMDAR encephalitis.
Introduction:
This study aimed to investigate the effectiveness of modifying the home environment on falls in older adults with dementia.
Methods:
In this single-blind clinical trial study, 44 older ...adult patients with dementia who met the inclusion criteria, were included in the study and then randomly assigned to intervention (n = 22) and control (n = 22) groups using a balanced block randomization method. The intervention group received home modifications, while the control group did not receive any modifications. After intervention, The HOME Fall and Accident Screening Tool was used to assess falls. The ethics committee of Tehran University of Medical Sciences approved the study procedure (IR.TUMS.FNM.REC.1399.163) and this study was registered in the Iranian Registry of Clinical Trials with the code: IRCT20210106049950N1.
Results:
Comparing the mean fall risk scores between the two groups at the beginning of the study showed no significant difference in the risk of falling (p = 0.6). By contrast, at the end of the study, this difference became significant between groups (p < 0.001). This comparison in the control group at the beginning and end of the study indicated no significant difference (p = 0.32). However, it was significant in the intervention group at the beginning of the study and after modifications (p < 0.001).
Conclusion:
Modifications by applying changes and reforms to the home environment reduced the risk of falling in older adults with dementia.
The present cross sectional study aimed to evaluate the construct and criterion validity, reliability, and gender and age differences of the 12-item General Health Questionnaire (GHQ-12) among ...hospitalized patients with COVID-19 in 2020. The criterion validity was assessed
its link with perceived stress, sleep quality, daily life activities, and demographic and medical characteristics.
A total of 328 COVID-19 patients (55.8% men; M
= 50.49, SD = 14.96) completed the GHQ-12, the Perceived Stress Scale (PSS), the Pittsburgh Sleep Quality Index (PSQI), the Activities of Daily Life (ADL)-Katz Scale, and the Lawton Instrumental Activities of Daily Living Scale (IADL).
Among 13 factorial models, the three-factor model (successful coping, self-esteem, and stress) was shown to have the best fit. GHQ-12 was positively associated with PSQI, PSS, Hyperlipidemia, psychiatry disorders, hospitalization duration, the change in sleep time, and use of sleeping pills, and negatively correlated with educational level, and the number of family members. The GHQ-12 also had a negative correlation with ADL and IADL in over 60 years of age group. Females scored higher on total GHQ-12 scores, compared to males. Finally, the hospitalization duration was longer for patients over 60 (mean = 8.8 days, SD = 5.9) than patients under 60 (mean = 6.35 days, SD = 5.87).
Overall, the findings provided evidence that mental distress in patients with COVID-19 is correlated with high perceived stress, low sleep quality, low ADL and IADL, and a range of demographic features and medical conditions. Designing psychological interventions for these patients that target the aforementioned correlates of mental distress is warranted.
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