Autism Spectrum Disorder (ASD), defined by deficits in social functioning, communication, and restricted interests/repetitive behaviors is a serious psychiatric disorder of childhood. Previous neuroimaging studies using task-based functional magnetic re...

We describe a frameless stereotaxic method for guiding recording electrode position. This involves two steps; Stereotaxic mapping of the brain to position a recording chamber, and subsequent stereotaxic mapping of the brain beneath the chamber expressed in chamber coordinates. Prior to surgery the animal undergoes T1 weighted 3D MR imaging, providing an anatomical dataset of 0.7mm resolution. The monkey is anesthetized for the MRI using a cocktail of ketamine, xylazine and atropine. Only light anesthesia is needed as the method requires no rigid stereotaxic fixation. Images are post-processed using AFNI software. The 3D image is rotated into the standard stereotaxic plane using skull/brain anatomy, and stereotaxic zero is set in the midline at the extended horizontal convergence of the external auditory meatii (to coincide with the surgical stereotaxic unit). This MRI is used to determine the optimal center and angle for surgically placing the recording chamber. Following attachment of the chamber the monk...

In order to understand the kinematics of the musculature controlling feeding in the marine mollusk Aplysia californica, we have developed a series of increasingly realistic kinematic models of the feeding apparatus, the buccal mass (Drushel et al., JEB, 1998; Chiel et al., Soc. Neurosci. Abstr., 1998, 1999). Using high spatial resolution MRI scans of freshly dissected buccal masses, a realistic external shape of the radula/odontophore at rest has been determined, which is approximated by modified ellipsoid octants. The surface of the radula is approximated by two planes that intersect the volume of the odontophore. By extracting parameters from high temporal resolution MRI taken of the buccal mass during swallowing movements in intact animals, it is possible to generate realistic shapes and positions for the radula/odontophore during the entire swallowing cycle, subject to the biological constraints that the total surface of the radula and the total volume of the odontophore are kept constant. To validate ...

Our objective has been to develop a direct cortical stimulation model for rodent functional magnetic resonance imaging (fMRI). Conventional fMRI studies in anaesthetised rodents are limited to the study of the somatosensory cortex via remote stimulation. Our approach has been to stimulate directly with stereotaxically placed carbon fibre electrodes over the hindpaw motor cortex in the rat to elicit movement of the contralateral limb. Using a 7T MRI system, blood oxygenation-level dependent (BOLD) signal changes can be detected using T2* weighted gradient echo imaging, to indicate which cortical areas are functionally active during stimulation. The most prominent signal changes occur in the region of the stimulated motor cortex. As with somatosensory responses, the haemodynamic response function timecourse is prolonged. This model of direct cortical stimulation will enable brain connectivity, functional recovery after injury, and drug responses to be investigated.

The use of testing during encoding is highly beneficial for long-term memory retention relative to classical repeated study strategies. This facilitation is known as the testing effect, and has been extensively demonstrated in behavioral research. Howev...

Leptomeningeal inflammation has been noted to occur in both multiple sclerosis (MS) patients and animal models of MS. Studies have demonstrated that areas of meningeal inflammation consist of B-cells, T-cells, follicular dendritic cells (FDC) and macrop...

Episodes of de- and remyelination, together with immune cells infiltration into the central nervous system (CNS) and inflammation, are recurrent hallmarks in several autoimmune and neurodegenerative diseases like multiple sclerosis (MS). Demyelination i...

PICALM, a gene encoding phosphatidylinositol-binding clathrin assembly protein is associated with Alzheimer’s disease (AD). Besides its well-known role in regulating intracellular trafficking of endocytic vesicles, studies in APPSw+/0; Picalm+/- mice re...

It is thought that motion sickness results from a conflict among different sensory modalities, such as the visual and vestibular senses. However, little is known about the impact that sensory conflicts within a sensory modality have on motion sickness. ...

Heavy smoking and heavy alcohol intake have been shown to be associated with morphology of specific brain regions. However, to what extent these factors impact brain aging on a whole-brain level remains unclear. To investigate this, we analyzed smoking,...