Low Subicular Volume as an Indicator of Dementia-Risk Susceptibility in Old Age.

Introduction: Hippocampal atrophy is an established Alzheimer's Disease (AD) biomarker. Volume loss in specific subregions as measurable with ultra-high field magnetic resonance imaging (MRI) may reflect earliest pathological alterations.

Methods: Data from positron emission tomography (PET) for estimation of cortical amyloid β (Aβ) and high-resolution 7 Tesla T1 MRI for assessment of hippocampal subfield volumes were analyzed in 61 non-demented elderly individuals who were divided into risk-categories as defined by high levels of cortical Aβ and low performance in standardized episodic memory tasks.

Memory deficits for facial identity in patients with amnestic mild cognitive impairment (MCI).

Faces are among the most relevant social stimuli revealing an encounter's identity and actual emotional state. Deficits in facial recognition may be an early sign of cognitive decline leading to social deficits. The main objective of the present study is to investigate if individuals with amnestic mild cognitive impairment show recognition deficits in facial identity.

Subcortical Shape Changes, Hippocampal Atrophy and Cortical Thinning in Future Alzheimer's Disease Patients.

Efficacy of future treatments depends on biomarkers identifying patients with mild cognitive impairment at highest risk for transitioning to Alzheimer's disease. Here, we applied recently developed analysis techniques to investigate cross-sectional differences in subcortical shape and volume alterations in patients with stable mild cognitive impairment (MCI) ( = 23, age range 59-82, 47.8% female), future converters at baseline ( = 10, age range 66-84, 90% female) and at time of conversion (age range 68-87) compared to group-wise age and gender matched healthy control subjects ( = 23, age range 61-81, 47.

Microstructural Integrity of Hippocampal Subregions Is Impaired after Mild Traumatic Brain Injury.

Mild traumatic brain injury (mTBI) affects a large number of individuals and diffusion tensor imaging can be used to investigate microstructural integrity of brain tissue after mTBI. However, results have varied considerably between studies and gray matter (GM) integrity has been largely neglected in these investigations. Given impaired working memory processing after mTBI and its possible association with Alzheimer's disease, we investigated hippocampal integrity and parcellated this structure into five subregions: subiculum, cornu ammonis (CA) 1, CA 2/3, CA 4/dentate gyrus, and stratum radiatum/lacunosum-moleculare.

Hippocampal shape alterations are associated with regional Aβ load in cognitively normal elderly individuals.

Aβ deposition is a driving force of Alzheimer's disease pathology and can be detected early by amyloid positron emission tomography. Identifying presymptomatic structural brain changes associated with Aβ deposition might lead to a better understanding of its consequences and provide early diagnostic information. In this respect we analyzed measures of cortical thickness and subcortical volumes along with hippocampal, thalamic and striatal shape and surface area by applying novel analysis strategies for structural magnetic resonance imaging.

Volumetric and shape analysis of the thalamus and striatum in amnestic mild cognitive impairment.

Alterations in brain structures, including progressive neurodegeneration, are a hallmark in patients with Alzheimer's disease (AD). However, pathological mechanisms, such as the accumulation of amyloid and the proliferation of tau, are thought to begin years, even decades, before the initial clinical manifestations of AD. In this study, we compare the brain anatomy of amnestic mild cognitive impairment patients (aMCI, n = 16) to healthy subjects (CS, n = 22) using cortical thickness, subcortical volume, and shape analysis, which we believe to be complimentary to volumetric measures.