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Parallel imaging in the form of multiband radiofrequency excitation, together with reduced k-space coverage in the phase-encode direction, was applied to human gradient echo functional MRI at 7 T for increased volumetric coverage and concurrent high spatial and temporal resolution. Echo planar imaging with simultaneous acquisition of four coronal slices(More)
The Human Connectome Project (HCP) is an ambitious 5-year effort to characterize brain connectivity and function and their variability in healthy adults. This review summarizes the data acquisition plans being implemented by a consortium of HCP investigators who will study a population of 1200 subjects (twins and their non-twin siblings) using multiple(More)
Since the commencement of functional magnetic resonance imaging (fMRI), great effort has been put into increasing its spatial resolution and signal specificity from vessel-weighted to more tissue-specific signals. The working assumption is that the "tissue" signals closely mirror changes at the neuronal level. While great progress has been made, the basic(More)
q-Ball imaging is a high-angular-resolution diffusion imaging technique that has been proven very successful in resolving multiple intravoxel fiber orientations in MR images. The standard computation of the orientation distribution function (the probability of diffusion in a given direction) from q-ball data uses linear radial projection, neglecting the(More)
Functional (f)MRI has revolutionized the field of human brain research. fMRI can noninvasively map the spatial architecture of brain function via localized increases in blood flow after sensory or cognitive stimulation. Recent advances in fMRI have led to enhanced sensitivity and spatial accuracy of the measured signals, indicating the possibility of(More)
Functional magnetic resonance imaging (fMRI) techniques are based on the assumption that changes in spike activity are accompanied by modulation in the blood oxygenation level-dependent (BOLD) signal. In addition to conventional increases in BOLD signals, sustained negative BOLD signal changes are occasionally observed and are thought to reflect a decrease(More)
The Human Connectome Project (HCP) relies primarily on three complementary magnetic resonance (MR) methods. These are: 1) resting state functional MR imaging (rfMRI) which uses correlations in the temporal fluctuations in an fMRI time series to deduce 'functional connectivity'; 2) diffusion imaging (dMRI), which provides the input for tractography(More)
BACKGROUND Deep brain stimulation (DBS) surgery is used for treating movement disorders, including Parkinson disease, essential tremor, and dystonia. Successful DBS surgery is critically dependent on precise placement of DBS electrodes into target structures. Frequently, DBS surgery relies on normalized atlas-derived diagrams that are superimposed on(More)
The precise wiring of the adult mammalian CNS originates during a period of stunning growth, guidance and plasticity that occurs during and shortly after development. When injured in adults, this intricate system fails to regenerate. Even when the obstacles to regeneration are cleared, growing adult CNS fibres usually remain misdirected and fail to reform(More)
We have assessed sound frequency and intensity responses in primary auditory cortex of the (ketamine) anesthetized chinchilla using optical imaging of intrinsic signals. Temporal cortex was exposed via a 10-mm craniotomy and a windowed chamber was mounted. A 4-second period of gated tones (10 ms rise/fall; 50 ms plateau; 10/s) was presented to the(More)