We determined the effect of cortical amyloid load using F-florbetapir PET on cognitive performance and gray matter structural integrity derived from MRI in 318 cognitively normally performing older people with subjective memory impairment from the INSIGHT-preAD cohort using multivariate partial least squares regression. Amyloid uptake was associated with reduced gray matter structural integrity in hippocampus, entorhinal and cingulate cortex, middle temporal gyrus, prefrontal cortex, and lentiform nucleus (p < 0.01, permutation test). Higher amyloid load was associated with poorer global cognitive performance, delayed recall and attention (p < 0.05), independently of its effects on gray matter connectivity. These findings agree with the assumption of a two-stage effect of amyloid on cognition, (1) an early direct effect in the preclinical stages of Alzheimer's disease and (2) a delayed effect mediated by downstream effects of amyloid accumulation, such as gray matter connectivity decline.
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http://dx.doi.org/10.1016/j.neurobiolaging.2017.05.016 | DOI Listing |
Neurol Genet
February 2025
Memory Center, Keio University School of Medicine, Tokyo, Japan.
Background And Objectives: A previous postmortem study of men with Christianson syndrome, a disorder caused by loss-of-function mutations in the gene , reported a mechanistic link between pathologic tau accumulation and progressive symptoms such as cerebellar atrophy and cognitive decline. This study aimed to characterize the relationships between neuropathologic manifestations and tau accumulation in heterozygous women with mutation.
Methods: We conducted a multimodal neuroimaging and plasma biomarker study on 3 middle-aged heterozygous women with mutations (proband 1: mid-50s; proband 2: early 50s; proband 3: mid-40s) presenting with progressive extrapyramidal symptoms.
Sci Rep
January 2025
Department of Radiology, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, 330006, Jiangxi, China.
The conventional statistical approach for analyzing resting state functional MRI (rs-fMRI) data struggles to accurately distinguish between patients with multiple sclerosis (MS) and those with neuromyelitis optic spectrum disorders (NMOSD), highlighting the need for improved diagnostic efficacy. In this study, multilevel functional metrics including resting state functional connectivity, amplitude of low frequency fluctuation (ALFF), and regional homogeneity (ReHo) were calculated and extracted from 116 regions of interest in the anatomical automatic labeling atlas. Subsequently, classifiers were developed using different combinations of these selected features to distinguish between MS and NMOSD.
View Article and Find Full Text PDFProg Neuropsychopharmacol Biol Psychiatry
January 2025
MOE-LCSM, School of Mathematics and Statistics, Hunan Normal University, Changsha 410006, PR China; Key Laboratory of Applied Statistics and Data Science, Hunan Normal University, College of Hunan Province, Changsha 410006, PR China. Electronic address:
Aging of the human brain involves intricate biological processes, resulting in complex changes in structure and function. While the effects of aging on gray matter (GM) connectivity are extensively studied, white matter (WM) functional changes have received comparatively less attention. This study examines age-related WM functional dynamics using resting-state fMRI across the adult lifespan.
View Article and Find Full Text PDFNeuroimage
January 2025
Department of Radiology, Columbia University Irving Medical Center, New York, NY; Department of Biomedical Engineering, Columbia University, New York, NY. Electronic address:
Background: The cortical gray matter-white matter interface (GWI) is a natural transition zone where the composition of brain tissue abruptly changes and is a location for pathologic change in brain disorders. While diffusion magnetic resonance imaging (dMRI) is a reliable and well-established technique to characterize brain microstructure, the GWI is difficult to assess with dMRI due to partial volume effects and is normally excluded from such studies.
Methods: In this study, we introduce an approach to characterize the dMRI microstructural profile across the GWI and to assess the sharpness of the microstructural transition from cortical gray matter (GM) to white matter (WM).
PLoS One
January 2025
Department of Neurology, Weill Cornell Medicine, New York, NY, United States of America.
Testosterone, an essential sex steroid hormone, influences brain health by impacting neurophysiology and neuropathology throughout the lifespan in both genders. However, human research in this area is limited, particularly in women. This study examines the associations between testosterone levels, gray matter volume (GMV) and cerebral blood flow (CBF) in midlife individuals at risk for Alzheimer's disease (AD), according to sex and menopausal status.
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