There has been tremendous interest in applying functional magnetic resonance imaging-based resting-state functional connectivity (rs-fcMRI) measurements to the study of brain function. However, a lack of understanding of the physiological mechanisms of rs-fcMRI limits their ability to interpret rs-fcMRI findings. In this work, the authors examine the regional associations between rs-fcMRI estimates and dynamic coupling between the blood oxygenation level-dependent (BOLD) and cerebral blood flow (CBF), as well as resting macrovascular volume.

BACKGROUND: Atrial fibrillation (AF) is a common cause of stroke. Silent cerebral infarctions (SCIs) are known to occur in the presence and absence of AF, but the association between these disorders has not been well-defined.
PURPOSE: To estimate the association between AF and SCIs and the prevalence of SCIs in stroke-free patients with AF.
DATA SOURCES: Searches of MEDLINE, PsycINFO, Cochrane Library, CINAHL, and EMBASE from inception to 8 May 2014 without language restrictions and manual screening of article references.

Brainstem nuclei (Bn) in humans play a crucial role in vital functions, such as arousal, autonomic homeostasis, sensory and motor relay, nociception, sleep, and cranial nerve function, and have been implicated in a vast array of brain pathologies. Yet, an in vivo delineation of most human Bn has been elusive because of limited sensitivity and contrast for detecting these small regions using standard neuroimaging methods.

The insula is uniquely located between the temporal and parietal cortices, making it anatomically well-positioned to act as an integrating center between the sensory and affective domains for the processing of painful stimulation. This can be studied through resting-state functional connectivity (fcMRI) imaging; however, the lack of a clear methodology for the analysis of fcMRI complicates the interpretation of this data during acute pain.

OBJECTIVES: This study evaluates the repeatability of brain perfusion using dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) with a variety of post-processing methods.

Recent computational models suggest that visual input from optic flow provides information about egocentric (navigator-centered) motion and influences firing patterns in spatially tuned cells during navigation. Computationally, self-motion cues can be extracted from optic flow during navigation. Despite the importance of optic flow to navigation, a functional link between brain regions sensitive to optic flow and brain regions important for navigation has not been established in either humans or animals.

Although much prior work has focused on the known cortical pathology that defines Alzheimer's disease (AD) histologically, recent work has additionally demonstrated substantial damage to the cerebral white matter in this condition. While there is large evidence of diffuse damage to the white matter in AD, it is unclear whether specific white matter tracts exhibit a more accelerated pattern of damage and whether the damage is associated with the classical neurodegenerative changes of AD.

Age-related impairments in the default network (DN) have been related to disruptions in connecting white matter tracts. We hypothesized that the local correlation between DN structural and functional connectivity is negatively affected in the presence of global white matter injury.

BACKGROUND & AIMS: Liver biopsy, the gold standard for assessing liver fibrosis, suffers from limitations due to sampling error and invasiveness. There is therefore a critical need for methods to non-invasively quantify fibrosis throughout the entire liver. The goal of this study was to use molecular Magnetic Resonance Imaging (MRI) of Type I collagen to non-invasively image liver fibrosis and assess response to rapamycin therapy.