The authors propose a statistical learning model for classifying cognitive processes based on distributed patterns of neural activation in the brain, acquired via functional magnetic resonance imaging (fMRI). In the proposed learning machine, local meshes are formed around each voxel. The distance between voxels in the mesh is determined by using functional neighborhood concept. In order to def...

The primary objective of the current prospective study was to examine developmental patterns of voxel-by-voxel gray and white matter volumes (GMV, WMV, respectively) that would predict psychosis in adolescents with 22q11.2 deletion syndrome (22q11.2DS), the most common known genetic risk factor for schizophrenia. We performed a longitudinal voxel-based morphometry analysis using structural T1 M...

The modulation of neural activity in visual cortex is thought to be a key mechanism of visual attention. The investigation of attentional modulation in high-level visual areas, however, is hampered by the lack of clear tuning or contrast response functions. In the present functional magnetic resonance imaging study we therefore systematically assessed how small voxel-wise biases in object prefe...

Despite growing interest in multi-voxel pattern analysis (MVPA) methods for fMRI, a major problem remains--that of generating estimates in rapid event-related (ER) designs, where the BOLD responses of temporally adjacent events will overlap. While this problem has been investigated for methods that reduce each event to a single parameter per voxel (Mumford et al., 2012), most of these methods m...

BACKGROUND Corticobasal syndrome (CBS) has a heterogeneous neuropathological spectrum, ranging from the classical corticobasal degeneration to Alzheimer's disease (AD). The neuropathology of CBS is still unpredictable. CSF tau/abeta ratio is a reliable marker of AD. OBJECTIVE To evaluate the presence of a distinct clinical and neuroimaging CBS phenotype according to CSF pattern. METHODS 30 ...

A novel method is presented for fully automatic detection of candidate white matter (WM) T1 hypointense lesions in three-dimensional high-resolution T1-weighted magnetic resonance (MR) images. By definition, T1 hypointense lesions have similar intensity as gray matter (GM) and thus appear darker than surrounding normal WM in T1-weighted images. The novel method uses a standard classification al...

Perceptual sensitivity to tactile roughness varies across individuals for the same degree of roughness. A number of neurophysiological studies have investigated the neural substrates of tactile roughness perception, but the neural processing underlying the strong individual differences in perceptual roughness sensitivity remains unknown. In this study, we explored the human brain activation pat...

BACKGROUND Fabry disease (FD) is a lysosomal storage disorder associated with marked cerebrovascular disease. Conventional MRI shows an extensive load of white matter lesions (WMLs) which may already be present at an early stage in the disease. OBJECTIVE Investigator independent and sensitive quantification of structural changes in the brain in clinically affected men and women with FD. MET...

OBJECTIVE Hemodynamic impairment in one hemisphere has been shown to trigger ipsilateral motor activation in the opposite hemisphere on functional imaging. We hypothesized that reversing the hypoperfusion would normalize the motor activation pattern. METHODS We studied four patients with high-grade stenosis and impaired vasomotor reactivity (VMR) but no stroke. Functional magnetic resonance i...

Functional magnetic resonance imaging (fMRI) has become a ubiquitous tool in cognitive neuroscience. The technique allows noninvasive measurements of cortical responses in the human brain, but only on the millimeter scale. Because a typical voxel contains many thousands of neurons with varied properties, establishing the selectivity of their responses directly is impossible. In recent years, tw...