Resting-state electroencephalographic correlates of cognitive reserve: Moderating the age-related decline in cognitive function

Measurement of cognitive reserve (CR) is a matter of constant reviews and developments due to the difficulty to assess it directly, being socio-behavioral indexes used as indirect proxies. An effort to unravel the neural correlates underlying CR seems mandatory, and strongly supported by the neuroscientific literature. Neurophysiological measures through electroencephalography (EEG) have proven to be a promising, almost inexpensive method to study the CR neural correlates. In line with the recommendations of Stern et al. (2020), the aim of the present study has been to demonstrate that resting-state EEG measures may moderate the relationship between age-related brain changes and cognitive status; thus, constituting an objective neural index of CR.Our results show that two resting-state EEG measures, delta current source density in the occipital region and beta 2 connectivity between limbic and occipital regions in the right hemisphere, moderate the relation between age and cognitive performance, indexing neuroprotective effects on cognition during the aging process. These results not only shed light on the neural mechanisms involved in CR but also allow us to propose features to be taken into account in order to enhance the results of interventions to delay the onset of cognitive deficits.

Plasma Lipocalin 2 in Alzheimer’s disease: potential utility in the differential diagnosis and relationship with other biomarkers

Background Lipocalin-2 is a glycoprotein that is involved in various physiological and pathophysiological processes. In the brain, it is expressed in response to vascular and other brain injury, as well as in Alzheimer’s disease in reactive microglia and astrocytes. Plasma Lipocalin-2 has been proposed as a biomarker for Alzheimer’s disease but available data is scarce and inconsistent. Thus, we evaluated plasma Lipocalin-2 in the context of Alzheimer’s disease, differential diagnoses, other biomarkers, and clinical data. Methods For this two-center case-control study, we analyzed Lipocalin-2 concentrations in plasma samples from a cohort of n = 407 individuals. The diagnostic groups comprised Alzheimer’s disease (n = 74), vascular dementia (n = 28), other important differential diagnoses (n = 221), and healthy controls (n = 84). Main results were validated in an independent cohort with patients with Alzheimer’s disease (n = 19), mild cognitive impairment (n = 27), and healthy individuals (n = 28). Results Plasma Lipocalin-2 was significantly lower in Alzheimer’s disease compared to healthy controls (p < 0.001) and all other groups (p < 0.01) except for mixed dementia (vascular and Alzheimer’s pathologic changes). Areas under the curve from receiver operation characteristics for the discrimination of Alzheimer’s disease and healthy controls were 0.783 (95%CI: 0.712–0.855) in the study cohort and 0.766 (95%CI: 0.627–0.905) in the validation cohort. The area under the curve for Alzheimer’s disease versus vascular dementia was 0.778 (95%CI: 0.667–0.890) in the study cohort. In Alzheimer’s disease patients, plasma Lipocalin2 did not show significant correlation with cerebrospinal fluid biomarkers of neurodegeneration and AD-related pathology (total-tau, phosphorylated tau protein, and beta-amyloid 1-42), cognitive status (Mini Mental Status Examination scores), APOE genotype, or presence of white matter hyperintensities. Interestingly, Lipocalin 2 was lower in patients with rapid disease course compared to patients with non-rapidly progressive Alzheimer’s disease (p = 0.013). Conclusions Plasma Lipocalin-2 has potential as a diagnostic biomarker for Alzheimer’s disease and seems to be independent from currently employed biomarkers.

A Cognitive Diagnosis Method in Adaptive Learning System Based on Preconceptions

One advantage of an adaptive learning system is the ability to personalize learning to the needs of individual users. Realizing this personalization requires first a precise diagnosis of individual users’ relevant attributes and characteristics and the provision of adaptability-enabling resources and pathways for feedback. In this paper, a preconcept system is constructed to diagnose users' cognitive status of specific learning content, including learning progress, specific preconcept viewpoint, preconcept source, and learning disability. The “Force and Movement” topic from junior high school physics is used as a case study to describe the method for constructing a preconception system. Based on the preconception system, a method and application process for diagnosing user cognition is introduced. This diagnosis method is used in three ways: firstly, as a diagnostic dimension for an adaptive learning system, improving the ability of highly-adaptive learning systems to support learning activities, such as through visualization of the cognition states of students; secondly, for an attribution analysis of preconceptions to provide a basis for adaptive learning organizations; and finally, for predicting the obstacles users may face in the learning process, in order to provide a basis for adaptive learning pathways.

Perceptions of Treatment Burden Among Caregivers of Elders With Diabetes and Co-morbid Alzheimer’s Disease and Related Dementias: A Qualitative Study

Many older adults with diabetes (DM) have co-occurring Alzheimer’s Disease (AD) and AD-Related Dementias (ADRD). Complex treatment plans may impose treatment burden for caregivers responsible for day-to-day self-management. The purpose of this qualitative study was to describe caregiver perceptions of treatment burden for people with DM-AD/ADRD. Caregivers ( n = 33) of patients with DM-AD/ADRD participated in semi-structured interviews about their caregiver role and perceptions of treatment burden of DM-AD/ADRD management. Qualitative data were analyzed using content analysis (ATLAS.ti). Caregivers reported high levels of burden related to complex treatment/self-management for patients with DM-AD/ADRD that varied day-to-day with the patient’s cognitive status. Four themes were: (1) trajectory of treatment burden; (2) navigating multiple healthcare providers/systems of care; (3) caregiver role conflict; and (4) emotional burden. Interventions to reduce caregiver treatment burden should include activating supportive services, education, and care coordination especially, if patient treatment increases in complexity over time.

Trans ε-Viniferin Decreases Amyloid Deposits With Greater Efficiency Than Resveratrol in an Alzheimer’s Mouse Model

In a previous study, we showed that viniferin decreased amyloid deposits and reduced neuroinflammation in APPswePS1dE9 transgenic mice between 3 and 6 months of age. In the present study, wild type and APPswePS1dE9 transgenic mice were treated from 7 to 11 or from 3 to 12 months by a weekly intraperitoneal injection of either 20 mg/kg viniferin or resveratrol or their vehicle, the polyethylene glycol 200 (PEG 200). The cognitive status of the mice was evaluated by the Morris water maze test. Then, amyloid burden and neuroinflammation were quantified by western-blot, Enzyme-Linked ImmunoSorbent Assay (ELISA), immunofluorescence, and in vivo micro-Positon Emission Tomography (PET) imaging. Viniferin decreased hippocampal amyloid load and deposits with greater efficiency than resveratrol, and both treatments partially prevented the cognitive decline. Furthermore, a significant decrease in brain uptake of the TSPO PET tracer [18F]DPA-714 was observed with viniferin compared to resveratrol. Expression of GFAP, IBA1, and IL-1β were decreased by viniferin but PEG 200, which was very recently shown to be a neuroinflammatory inducer, masked the neuroprotective power of viniferin.

The Effect of Micronutrient Intake on Cognitive Function and Physical Activity of the Elderly

Objectives: The purpose of this research was to investigate the effect of micronutrient intake on cognitive function and physical activity of the elderly. Methods: The subjects included all elderly people over 60 years of age in Robat Karim city in 2018. 90 elderly males participated voluntarily in the research after signing the informed consent form. The short form of Beck questionnaire of physical activity and MMSE test were respectively used to measure the levels of physical activity and cognitive status of participants. Pearson correlation test was used to analyze the data. Results: The results indicated that there was a significant relationship between each of the micronutrients and cognitive performance of the elderly (P ≤ 0.05). Additionally, there was a significant relationship between each of the micronutrients with the level of physical activity of the elderly (P ≤ 0.05). Conclusions: Conclusively, micronutrients intake could be of much importance for cognitive function and physical activity of the elderly.

Apathy-Related Symptoms Appear Early in Parkinson’s Disease

Background: Apathy, often-unrecognized in Parkinson’s Disease (PD), adversely impacts quality-of-life (QOL) and may increase with disease severity. Identifying apathy early can aid treatment and enhance prognoses. Whether feelings related to apathy (e.g., loss of pleasure) are present in mild PD and how apathy and related feelings increase with disease severity is unknown. Methods: 120 individuals (M age: 69.0 ± 8.2 y) with mild (stages 1–2, n = 71) and moderate (stages 2.5–4; n = 49) PD were assessed for apathy and apathy-related constructs including loss of pleasure, energy, interest in people or activities, and sex. Correlations were used to determine the association of apathy with apathy-related constructs. Regression models, adjusted for age, cognitive status, and transportation, compared groups for prevalence of apathy and apathy-related feelings. Results: Apathy-related constructs and apathy were significantly correlated. Apathy was present in one in five participants with mild PD and doubled in participants with moderate PD. Except for loss of energy, apathy-related constructs were observed in mild PD at a prevalence of 41% or greater. Strong associations were noted between all apathy-related constructs and greater disease severity. After adjustment for transportation status serving as a proxy for independence, stage of disease remained significant only for loss of pleasure and loss of energy. Conclusion: People with mild PD showed signs of apathy and apathy-related feelings. Loss of pleasure and energy are apathy-related feelings impacted by disease severity. Clinicians should consider evaluating for feelings related to apathy to enhance early diagnosis in individuals who might otherwise not exhibit psychopathology.

Burden of Insomnia and Sleep Disturbances and the Impact of Sleep Treatments in Patients with Probable or Possible Alzheimer’s Disease: A Structured Literature Review

Background: Sleep disturbances are frequent in Alzheimer’s disease (AD). This review summarizes the impact of sleep disturbances on AD patients and their caregivers and the effects of currently available sleep therapies. Methods: Published studies (January 1985–March 2020) assessing the burden associated with insomnia/sleep disturbances in the AD population and insomnia treatment effects were identified by searching PubMed, Embase and Cochrane Library and screened against inclusion criteria. Findings: This review included 58 studies which assessed patient and caregiver burden, institutionalization, and insomnia treatments in AD patients with sleep disturbances. Sleep disturbances were associated with worse cognition, functional ability, and behavioral and neuropsychological functioning, including increased depression and anxiety. Health status and quality of life of both patients and caregivers were reduced in the presence of sleep disturbances, with caregiver burden driven largely by disruptive nocturnal behaviors including nighttime awakenings and wanderings. Sleep disturbances were also associated with institutionalization. Although significant associations between sleep problems and clinical outcomes were apparent, there was generally no control for other influencing factors (e.g. cognitive status). With respect to insomnia treatments, bright light, and behavioral therapies as well as drugs such as trazodone, risperidone and suvorexant showed some promise in AD patients, but studies were primarily small and limited data were available, particularly in regard to insomnia treatment effects on associated clinical burden. Interpretation: Sleep disturbances are a significant problem for AD patients and caregivers. They are associated with behavioral and psychological problems and cognitive decline and impose a burden on caregivers, but remain poorly characterized and under-researched. As the global population is aging and AD is on the rise, data from larger, prospective trials are required to fully understand the clinical correlates of sleep disturbances and the impact of insomnia treatments on AD patients and their caregivers.