Chronic Hyponatremia and Brain Structure and Function Before and After Treatment.

Rationale & Objective: Hyponatremia is the most common electrolyte disorder and is associated with significant morbidity and mortality. This study investigated neurocognitive impairment, brain volume, and alterations in magnetic resonance imaging (MRI)-based measures of cerebral function in patients before and after treatment for hyponatremia.

Study Design: Prospective cohort study.

Improved connectivity and cognition due to cognitive stimulation in Alzheimer's disease.

Background: Due to the increasing prevalence of Alzheimer's disease (AD) and the limited efficacy of pharmacological treatment, the interest in non-pharmacological interventions, e.g., cognitive stimulation therapy (CST), to improve cognitive dysfunction and the quality of life of AD patients are on a steady rise.

Serum cortisol is negatively related to hippocampal volume, brain structure, and memory performance in healthy aging and Alzheimer's disease.

Objective: Elevated cortisol levels have been frequently reported in Alzheimer's disease (AD) and linked to brain atrophy, especially of the hippocampus. Besides, high cortisol levels have been shown to impair memory performance and increase the risk of developing AD in healthy individuals. We investigated the associations between serum cortisol levels, hippocampal volume, gray matter volume and memory performance in healthy aging and AD.

Decreased Efficiency of Between-Network Dynamics During Early Memory Consolidation With Aging.

Aging is associated with memory decline and progressive disabilities in the activities of daily living. These deficits have a significant impact on the quality of life of the aging population and lead to a tremendous burden on societies and health care systems. Understanding the mechanisms underlying aging-related memory decline is likely to inform the development of compensatory strategies promoting independence in old age.

[Brain Stimulation for the Treatment of Dementia].

Due to the increasing number of cases of Alzheimer's disease and the relatively moderate success with the available symptomatic and causal pharmacological therapies, there is a considerable need to explore non-pharmacological treatment options. In the field of non-invasive brain stimulation (NIBS), various methods have been investigated, particularly transcranial magnetic stimulation and transcranial electrical stimulation. In addition, deep brain stimulation (DBS) is currently being researched as an innovative method for targeted neuromodulation.

Concordance of Intrinsic Brain Connectivity Measures Is Disrupted in Alzheimer's Disease.

Recently, a new resting-state functional magnetic resonance imaging (rs-fMRI) measure to evaluate the concordance between different rs-fMRI metrics has been proposed and has not been investigated in Alzheimer's disease (AD). 3T rs-fMRI data were obtained from healthy young controls (YC,  = 26), healthy senior controls (SC,  = 29), and AD patients ( = 35). The fractional amplitude of low-frequency fluctuations (fALFF), regional homogeneity (ReHo), and degree centrality (DC) were analyzed, followed by the calculation of their concordance using Kendall's W for each brain voxel across time.

Graph Theory Analysis Reveals Resting-State Compensatory Mechanisms in Healthy Aging and Prodromal Alzheimer's Disease.

Several theories of cognitive compensation have been suggested to explain sustained cognitive abilities in healthy brain aging and early neurodegenerative processes. The growing number of studies investigating various aspects of task-based compensation in these conditions is contrasted by the shortage of data about resting-state compensatory mechanisms. Using our proposed criterion-based framework for compensation, we investigated 45 participants in three groups: (i) patients with mild cognitive impairment (MCI) and positive biomarkers indicative of Alzheimer's disease (AD); (ii) cognitively normal young adults; (iii) cognitively normal older adults.