The pons is one of the brain areas demonstrating selective degeneration in Machado-Joseph disease (MJD), which is caused by the expansion of a polyglutamine stretch in the protein called ataxin-3. Although the resultant pontine atrophy is readily recognized by magnetic resonance imaging (MRI), the features and natural process of atrophy is not fully understood. To characterize these, we analyzed the midsagittal images of pons obtained by MRI. We found a difference in atrophy between the pontine base and tegmentum. The reduced size of the pontine tegmentum was prominent early after the onset of clinical symptoms. No overlap was seen in the range of the area of pontine tegmentum between MJD and controls. The quotient of atrophy of the pontine tegmentum divided by age correlated well with the CAG repeat number. In contrast, the area of the pontine base correlated negatively with disease duration. Particularly, the size of pontine base appeared to remain in the range of controls for a relatively long time afte...

We describe the first systematic functional magnetic resonance imaging (fMRI) measurements of visual field maps in macaque visual cortex. The boundaries of visual areas V1, V2, V3, V3A, V4, MT/V5, and TEO/V4A were identified using stimuli that create traveling waves of activity in retinotopically organized areas of the visual cortex. Furthermore, these stimuli were used to measure the dimensions of the representations of the central 11° in V1–V3, quantitative visual field eccentricity functions for V1–V3 and MT, and the distribution of foveal and peripheral signals within the occipital lobe. Within areas V1, V2, MT, and portions of V4, the fMRI signals were 5–10 times the noise level (3 mm3 volumes of interest). Signals were weaker but still significant in other cortical regions, including V3, V3A, and TEO. There is good agreement between the fMRI maps and the visual area maps discovered using local anatomical and physiological measurements. The fMRI measurements allow one to obtain a broad view of the dis...

Stereoscopic vision enables the perception of depth. To study the brain mechanisms behind stereoscopic vision using noninvasive brain imaging (magnetic resonance brain imaging; MRI), scientists need to reproduce the independent views of the left and right eyes in the brain scanner using “dichoptic” displays. However, high-quality dichoptic displays are technically challenging and costly to implement in the MRI scanner. The novel miniature stereoscope system (“MRI stereoscope”) is an affordable and open-source tool that displays high-quality dichoptic images inside the MRI scanner. The MRI stereoscope takes advantage of commonly used display equipment, the MRI head coil, and a display screen. To validate the MRI stereoscope, binocular disparity stimuli were presented in a 3T MRI scanner while neural activation was recorded using functional MRI in six human participants. The comparison of large binocular disparities compared with disparities close to zero evoked strong responses across dorsal and ventral ext...

The spastic Han-Wistar (sHW) rat suffers from glutamate excitotoxicity causing the observed neurodegeneration within the cerebellum (Purkinje cells) and hippocampus (CA3 pyramidal cells). Mutants homozygous for the autosomal trait begin to exhibit motor tremor and hind limb rigidity as early as 25 days of age with progressive ataxic symptoms resulting in mortality at 60 days of age. We hypothesized that this neurodegeneration could be observed non-invasively using magnetic resonance imaging (MRI) and spectroscopy (MRS) of selected brain regions in the sHW rat. Mutant and normal siblings were imaged at 4.7 T using T2- and diffusion-weighted imaging (DWI), and MRS at 25, 40, and 55 days post-natal. Neurodegeneration in the hippocampus, retrospinal and piriform cortices, and cerebellum were quantified and brain volume reductions were calculated. MRS assessment of brain metabolites was limited to the hippocampus. At 55 days, subjects were sacrificed and imaged at 11.7 T for MR microscopy, followed by conventio...

Spinal cord injury (SCI) is described by the neurological level and severity of impairment using the ASIA Impairment Scale and the International Standards for Neurological Classification of Spinal Cord Injury. Magnetic resonance imaging (MRI) of the spi...

The aim of this study was to validate transcription magnetic resonance imaging (transcription MRI or tMRI) for gene transcript targeting in acute neurological disorders in live subjects. In a global cerebral ischemia model using bilateral carotid occlus...

Magnetic Resonance Imaging (MRI) has recently succeeded in illustrating structural detail in the brain at microscopic resolution, especially when images are acquired, at high Tesla and in optimal ex vivo conditions from formalin fixed tissue. The cerebr...

Magnetic resonance imaging (MRI) is widely used to evaluate the level and extent of a spinal cord injury in humans. To investigate new pharmacological approaches the rat model can be expected to be the major experimental model. In both species, rat and humans, a fibrous scar forms within one week after injury after spinal cord injury (SCI), which has been shown to impede axonal regeneration in the rat model. Histologically, the fibrous scar can be detected by applying antibodies against collagen IV, whereas the glial scar is detected by staining of GFAP-positive astrocytes. The aim of the present study was to establish an in-vivo-model for monitoring scar development and to correlate MR with histological findings. The lesion can unequivocally be identified already after one day. Our therapeutic intervention to enable axonal regeneration in an experimental SCI model inhibited transiently collagenous scar formation. To investigate whether this therapeutic approach can be visualized in vivo, we applied 3D-Se ...

Magnetic resonance imaging (MRI)-guided focused ultrasound has recently been developed to produce focal lesion of deep brain structures without the need for skull incision. The objective of this study was to test the effects of focused ultrasound subtha...

The modern “obesogenic” environment is characterized by an abundance of readily available hyperpalatable, energy-dense foods. These foods are highly valued and extremely rewarding: exposure to these foods and associated cues activates a diverse brain network underlying reward processing and