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Functional connectivity (FC) between brain regions is thought to be central to the way in which the brain processes information. Abnormal connectivity is thought to be implicated in a number of diseases. The ability to study FC is therefore a key goal for neuroimaging. Functional connectivity (fc) MRI has become a popular tool to make connectivity(More)
A salience network, comprising bilateral insula and anterior cingulate cortex (ACC), is thought to play a role in recruiting relevant brain regions for the processing of sensory information. Here, we present a functional network connectivity (FNC) analysis of spatial networks identified during somatosensation, performed to test the hypothesis that salience(More)
Blood oxygenation level dependent (BOLD) signal changes occurring during execution of a simple motor task were measured at field strengths of 1.5, 3 and 7 T using multi-slice, single-shot, gradient echo EPI at a resolution of 1x1x3 mm(3), to quantify the benefits offered by ultra-high magnetic field for functional MRI. Using four different echo times at(More)
Ankle dorsiflexion (ADF) is an integral component in gait. The objective of this study was to define, using functional magnetic resonance imaging (fMRI) in healthy volunteers (n=12), the brain regions that are activated during Electrical Stimulation (ES)-induced ADF movements, and compare this to the pattern of activation occurring during active and passive(More)
This study aims to improve the method used to produce cerebrovascular reactivity (CVR) maps by MRI. Previous methods have used a standard boxcar presentation of carbon dioxide (CO(2)). Here this is replaced with a sinusoidally modulated CO(2) stimulus. This allowed the use of Fourier analysis techniques to measure both the amplitude and phase delay of the(More)
The rewarding attributes of foods containing fat are associated with the increase in fat consumption, but little is known of how the complex physical and chemical properties of orally ingested fats are represented and decoded in the brain nor how this impacts feeding behavior within the population. Here, functional MRI (fMRI) is used to assess the brain(More)
OBJECT The sensitivity of spin echo (SE) experiments to blood oxygenation level dependent (BOLD) contrast was explored in a study of the same six subjects carried out at 3 and 7 T. MATERIALS AND METHODS Multi-slice, single shot, spin echo, echo planar images with a voxel size of 1 x 1 x 3 mm3 were acquired at three different echo times, during execution(More)
This paper introduces a lead field formulation for use in beamformer analysis of MEG data. This 'dual source beamformer' is a technique to image two temporally correlated sources using beamformer methodology. We show that while the standard, single source beamformer suppresses the reconstructed power of two spatially separate but temporally correlated(More)
fMRI studies of brain activity at rest study slow (<0.1 Hz) intrinsic fluctuations in the blood-oxygenation-level-dependent (BOLD) signal that are observed in a temporal scale of several minutes. The origin of these fluctuations is not clear but has previously been associated with slow changes in rhythmic neuronal activity resulting from changes in cortical(More)
Two studies were carried out to assess the applicability of echoplanar fMRI at 3.0 T to the analysis of somatosensory mechanisms in humans. Vibrotactile stimulation of the tips of digits two and five reliably generated significant clusters of activation in primary (SI) and secondary (SII) somatosensory cortex, area 43, the pre-central gyrus, posterior(More)