Magnetic Resonance Imaging (MRI)

Using MRI techniques, we show here that normalization of tumor vessels in recurrent glioblastoma patients by daily administration of AZD2171-an oral tyrosine kinase inhibitor of VEGF receptors-has rapid onset, is prolonged but reversible, and has the significant clinical benefit of alleviating edema. Reversal of normalization began by 28 days, though some features persisted for as long as four months.

What are the basic visual cues that determine our preference towards mundane everyday objects? We previously showed that a highly potent cue is the nature of the object's contour: people generally like objects with a curved contour compared with objects that have pointed features and a sharp-angled contour. This bias is hypothesized here to stem from an implicit perception of potential threat conveyed by sharp elements.

How do category-selective regions arise in human extrastriate cortex? Visually presented words provide an ideal test of the role of experience: Although individuals have extensive experience with visual words, our species has only been reading for a few thousand years, a period not thought to be long enough for natural selection to produce a genetically specified mechanism dedicated to visual word recognition per se.

An eight-rung, 3T degenerate birdcage coil (DBC) was constructed and evaluated for accelerated parallel excitation of the head with eight independent excitation channels. Two mode configurations were tested. In the first, each of the eight loops formed by the birdcage was individually excited, producing an excitation pattern similar to a loop coil array. In the second configuration a Butler matrix transformed this "loop coil" basis set into a basis set representing the orthogonal modes of the birdcage coil.

Spontaneous electromagnetic brain rhythms have been widely used in human neuropharmacology, but their applicability is complicated by the difficulties to localize their origins in the human cortex. Here, we used a novel multi-modal non-invasive imaging approach to localize lorazepam (30 microg/kg i.v.) modulation of cortical generators of spontaneous brain rhythms. Eight healthy subjects were measured with 306-channel magnetoencephalography (MEG) in a double-blind, randomized, placebo-controlled (saline), crossover design.

Functional magnetic resonance imaging (fMRI) has become a powerful tool for studying the normal and diseased human brain. The application of fMRI in detecting neuronal signals in the trigeminal system, however, has been hindered by low detection sensitivity due to activation artifacts caused by cardiac pulse-induced brain and brainstem movement. A variety of cardiac gating techniques have been proposed to overcome this issue, typically by phase locking the sampling to a particular time point during each cardiac cycle.

Introversion/extraversion and neuroticism are 2 important and frequently studied dimensions of human personality. These dimensions describe individual differences in emotional responding across a range of situations and may contribute to a predisposition for psychiatric disorders. Recent neuroimaging research has begun to provide evidence that neuroticism and introversion/extraversion have specific functional and structural neural correlates.

Activation of the amygdala to emotionally valenced stimuli, and particularly to fearful faces, has been widely demonstrated in healthy young adults. However, recent studies assessing amygdala responses to fearful emotional faces in the normal elderly have not shown similar results. The reason for this is uncertain, but it may relate to life-span developmental changes in processing emotional stimuli or structural alterations in the amygdala with aging.

A 32-channel 3T receive-only phased-array head coil was developed for human brain imaging. The helmet-shaped array was designed to closely fit the head with individual overlapping circular elements arranged in patterns of hexagonal and pentagonal symmetry similar to that of a soccer ball. The signal-to-noise ratio (SNR) and noise amplification (g-factor) in accelerated imaging applications were quantitatively evaluated in phantom and human images and compared with commercially available head coils.

The aim of this study was to determine the role of regional cortical thickness in recall of verbal material over an extended time period. MRI scans of healthy adults of varying ages were obtained. Two scans were averaged per person to achieve high spatial resolution, and a semi-automated method for continuous measurement of thickness across the entire cortical mantle was employed. Verbal memory tests assessing recall after 5 min, 30 min, and a mean interval of 83 days were administered.