Automated segmentation of midbrain nuclei using deep learning and multisequence MRI: A longitudinal study on iron accumulation with age.

Elevated levels of brain iron, particularly within the basal ganglia, have been associated with cognitive and motor impairment in normal aging and neurodegenerative conditions. The subthalamic nucleus (STN), substantia nigra (SN), and red nucleus (RN), despite their high iron content and contribution to motor and cognitive processes, are less frequently studied. This oversight can largely be attributed to the challenges posed by in-vivo assessments of these small, deep-seated midbrain structures.

Sleep health associations with serum metabolites in healthy adults.

Study Objectives: Short and long sleep duration as well as poor sleep quality have been linked to higher prevalence of metabolic disorders. However, it is still unclear how diverse sleep variables relate to different metabolic pathways. This study examines how different features of sleep health relate to serum metabolites.

Long-Term Exposure to Ambient Particulate Matter and Structural Brain Changes in Older Adults.

Background: Accumulating evidence links air pollution exposure to late-life cognitive deterioration. Whether air pollution alters brain structure remains poorly understood. Thus, we aimed to quantify the association between long-term exposure to particulate matter ≤2.

Corrigendum: Cerebrovascular burden and neurodegeneration linked to 15-year odor identification decline in older adults.

[This corrects the article DOI: 10.3389/fnagi.2025.

Cerebrovascular burden and neurodegeneration linked to 15-year odor identification decline in older adults.

Background: The mechanisms underlying olfactory decline in aging need further investigation. Noticeably, the longitudinal relationship of biological markers with olfaction remains underexplored. We investigated whether baseline levels and progression of microvascular lesions and brain atrophy are associated with odor identification (OID) decline.

Structure-function relationships in the human aging brain: An account of cross-sectional and longitudinal multimodal neuroimaging studies.

The patterns of brain activation and functional connectivity, task-related and task-free, as a function of age have been well documented over the past 30 years. However, the aging brain undergoes structural changes that are likely to affect the functional properties of the brain. The relationship between brain structure and function started to be investigated more recently.

Lifestyle, biological, and genetic factors related to brain iron accumulation across adulthood.

Iron is necessary for many neurobiological mechanisms, but its overaccumulation can be harmful. Factors triggering age-related brain iron accumulation remain largely unknown and longitudinal data are insufficient. We examined associations between brain iron load and accumulation and, blood markers of iron metabolism, cardiovascular health, lifestyle factors (smoking, alcohol use, physical activity, diet), and ApoE status using longitudinal data from the IronAge study (n = 208, age = 20-79, mean follow-up time = 2.

Lung function in relation to brain aging and cognitive transitions in older adults: A population-based cohort study.

Background: We investigated the association of peak expiratory flow (PEF) with dementia; cognitive impairment, no dementia (CIND); and transition from CIND to dementia, and possible underlying neuropathological mechanisms.

Methods: A population-based cohort of adults aged 60+ was followed over 15 years to detect dementia (Diagnostic and Statistical Manual of Mental Disorders, 4th edition criteria), CIND (assessed through a cognitive battery), and progression from CIND to dementia, in relation to baseline PEF observations. A subsample (n = 462) had 6-year follow-up data on brain magnetic resonance imaging markers of neurodegeneration and small vessel disease.

Association of cognitive reserve with transitions across cognitive states and death in older adults: A 15-year follow-up study.

Introduction: We investigated the association of cognitive reserve (CR) with transitions across cognitive states and death.

Methods: This population-based cohort study included 2631 participants (age ≥60 years) who were dementia-free at baseline and regularly examined up to 15 years. Data were analyzed using the Markov multistate models.

Association of mild and complex multimorbidity with structural brain changes in older adults: A population-based study.

Introduction: We quantified the association of mild (ie, involving one or two body systems) and complex (ie, involving ≥3 systems) multimorbidity with structural brain changes in older adults.

Methods: We included 390 dementia-free participants aged 60+ from the Swedish National Study on Aging and Care in Kungsholmen who underwent brain magnetic resonance imaging at baseline and after 3 and/or 6 years. Using linear mixed models, we estimated the association between multimorbidity and changes in total brain tissue, ventricular, hippocampal, and white matter hyperintensities volumes.

The iron-dopamine D1 coupling modulates neural signatures of working memory across adult lifespan.

Brain iron overload and decreased integrity of the dopaminergic system have been independently reported as brain substrates of cognitive decline in aging. Dopamine (DA), and iron are co-localized in high concentrations in the striatum and prefrontal cortex (PFC), but follow opposing age-related trajectories across the lifespan. DA contributes to cellular iron homeostasis and the activation of D1-like DA receptors (D1DR) alleviates oxidative stress-induced inflammatory responses, suggesting a mutual interaction between these two fundamental components.

Anosmia, mild cognitive impairment, and biomarkers of brain aging in older adults.

Olfactory impairment is a potential marker for prodromal dementia, but the underlying mechanisms are poorly understood. This population-based study included 4214 dementia-free participants (age ≥65 years). Olfaction was assessed using the 16-item Sniffin' Sticks identification test.

Association Between Behavioral, Biological, and Genetic Markers of Cardiovascular Health and MRI Markers of Brain Aging: A Cohort Study.

Background And Objective: The life's simple 7 approach was proposed to define cardiovascular health (CVH) metrics. We sought to investigate the associations between behavioral, biological, and genetic markers for CVH and vascular brain aging in older adults.

Methods: This population-based cohort study included participants who had repeated brain MRI measures from 2001 to 2003 to 2007-2010 (i.

Brain Changes and Fast Cognitive and Motor Decline in Older Adults.

Background: To identify brain magnetic resonance imaging (MRI) signatures characterizing people with different patterns of decline in cognition and motor function.

Methods: In the Swedish National Study on Aging and Care in Kungsholmen, Stockholm, 385 participants had available repeated brain MRI examinations, where markers of brain volumes and white matter integrity were assessed. The speed of cognitive and motor decline was estimated as the rate of a Mini-Mental State Examination and gait speed decline over 12 years (linear mixed models), and further dichotomized into the upper (25% fastest rate of decline) versus the lower quartiles.

Contributions of the Catechol-O-Methyltransferase Val158Met Polymorphism to Changes in Brain Iron Across Adulthood and Their Relationships to Working Memory.

Ageing is associated with excessive free brain iron, which may induce oxidative stress and neuroinflammation, likely causing cognitive deficits. Lack of dopamine may be a factor behind the increase of iron with advancing age, as it has an important role in cellular iron homoeostasis. We investigated the effect of Val 158 Met (rs4680), a polymorphism crucial for dopamine degradation and proxy for endogenous dopamine, on iron accumulation and working memory in a longitudinal lifespan sample ( = 208, age 20-79 at baseline, mean follow-up time = 2.

DyNAMiC: A prospective longitudinal study of dopamine and brain connectomes: A new window into cognitive aging.

Concomitant exploration of structural, functional, and neurochemical brain mechanisms underlying age-related cognitive decline is crucial in promoting healthy aging. Here, we present the DopamiNe, Age, connectoMe, and Cognition (DyNAMiC) project, a multimodal, prospective 5-year longitudinal study spanning the adult human lifespan. DyNAMiC examines age-related changes in the brain's structural and functional connectome in relation to changes in dopamine D1 receptor availability (D1DR), and their associations to cognitive decline.

Progression of neuroimaging markers of cerebral small vessel disease in older adults: A 6-year follow-up study.

We investigated progression and interrelationships of cerebral small vessel disease (cSVD) markers. This population-based cohort study included 325 participants (age ≥ 60 years) who had repeated measures of cSVD markers over 6 years: white-matter hyperintensity (WMH), perivascular spaces (PVS), lacunes, and grey-matter (GM) and ventricular volumes. We found that all cSVD markers, except PVS, progressed faster with increasing age.

Cerebral small vessel disease, cardiovascular risk factors, and future walking speed in old age: a population-based cohort study.

Background: The purpose of this study was to examine the associations between combined and individual cerebral small vessel disease (cSVD) markers on future walking speed over 9 years; and to explore whether these associations varied by the presence of cardiovascular risk factors (CRFs).

Methods: This population-based cohort study included 331 adults, aged ≥60 years, without limitation in walking speed (≥0.8 m/s).

Cognitive Trajectories and Dementia Risk: A Comparison of Two Cognitive Reserve Measures.

Background And Objectives: Cognitive reserve (CR) is meant to account for the mismatch between brain damage and cognitive decline or dementia. Generally, CR has been operationalized using proxy variables indicating exposure to enriching activities ( CR). An alternative approach defines CR as residual variance in cognition, not explained by the brain status ( CR).

Contributions of HFE polymorphisms to brain and blood iron load, and their links to cognitive and motor function in healthy adults.

Background: Brain iron overload is linked to brain deterioration, and cognitive and motor impairment in neurodegenerative disorders and normal aging. Mutations in the HFE gene are associated with iron dyshomeostasis and are risk factors for peripheral iron overload. However, links to brain iron load and cognition are less consistent and data are scarce.

Cerebral Small Vessel Disease Associated With Atrial Fibrillation Among Older Adults: A Population-Based Study.

Background And Purpose: Cerebral small vessel disease, as a potential mechanism underlying the association between atrial fibrillation (AF) and dementia, remains poorly investigated. In this cohort study, we sought to examine the association between AF and cerebral small vessel disease markers among older adults.

Methods: Data on 336 participants (age ≥60 years, mean 70.