A5036286159- Advanced MRI Techniques and Applications
- Functional Brain Connectivity Studies
- Advanced Neuroimaging Techniques and Applications
- Atomic and Subatomic Physics Research
- Transcranial Magnetic Stimulation Studies
- NMR spectroscopy and applications
- EEG and Brain-Computer Interfaces
- Cerebrospinal fluid and hydrocephalus
- Advanced NMR Techniques and Applications
- Vestibular and auditory disorders
- MRI in cancer diagnosis
- Alzheimer's disease research and treatments
- Bone health and osteoporosis research
- Traumatic Brain Injury and Neurovascular Disturbances
- Medical Imaging Techniques and Applications
- Marine Toxins and Detection Methods
- Neuroscience of respiration and sleep
- Neurological disorders and treatments
- Neonatal and fetal brain pathology
- Neuroscience and Neuropharmacology Research
- Electron Spin Resonance Studies
- Zebrafish Biomedical Research Applications
- Pain Management and Placebo Effect
- Bone and Joint Diseases
- Radioactive Decay and Measurement Techniques
University of California, Berkeley
2016-2025
Imaging Center
2016-2025
Neurosciences Institute
2024
University of Florida
1996-2002
Francis Marion University
2002
National High Magnetic Field Laboratory
2001
We use a novel balanced experimental design to specifically investigate brain mechanisms underlying the modulating effect of expected pain intensity on afferent nociceptive processing and perception. used two visual cues, each conditioned one noxious thermal stimuli [∼48°C (high) or 47°C (low)]. The cues were presented just before during application stimulus. Subjects reported significantly higher when stimulus was preceded by high-intensity cue. To control for expectancy effects, one-half...
Alzheimer's disease researchers have been intrigued by the selective regional vulnerability of brain to amyloid-β plaques and tau neurofibrillary tangles. Post-mortem studies indicate that in ageing tangles deposit early transentorhinal cortex, a region located anterior-temporal lobe is critical for object memory. In contrast, pathology seems target posterior-medial network subserves spatial current study, we tested whether regions are selectively vulnerable deposition progression from this...
Abstract In pathologies in which slow or collateral flow conditions may exist, conventional arterial spin labeling (ASL) methods that apply magnetic tags based on the location of spins not provide robust measures cerebral blood (CBF), as transit delay for delivery to target tissues far exceed relaxation time tag. Here we describe current ASL with velocity‐selective (VS) (termed VSASL) do require spatial selectivity and can thus quantitative CBF under conditions. The implementation a...
It is commonly believed that cerebrospinal fluid (CSF) movement facilitated by blood vessel wall movements (i.e., hemodynamic oscillations) in the brain. A coherent pattern of low frequency oscillations and CSF was recently found during non-rapid eye (NREM) sleep via functional MRI. This finding raises other fundamental questions: 1) explanation coupling between from fMRI signals; 2) existence wakefulness; 3) direction movement. In this resting state study, we proposed a mechanical model to...
Abstract The magnitude and shape of blood oxygen level‐dependent (BOLD) responses in functional MRI (fMRI) studies vary across brain regions, subjects, populations. This variability may be secondary to neural activity or vasculature differences, thus complicating interpretations BOLD signal changes fMRI experiments. We compare the a vascular challenge test method dissociate these influences 26 younger subjects (ages 18–36) 24 older 51–78). Each subject performed visuomotor saccade task (a...
Globally, the demand for improved health care delivery while managing escalating costs is a major challenge. Measuring biomagnetic fields that emanate from human brain already impacts treatment of epilepsy, tumours and other disorders. This roadmap explores how superconducting technologies are poised to impact care. Biomagnetism study magnetic biological origin. Biomagnetic typically very weak, often in femtotesla range, making their measurement challenging. The earliest vivo measurements...
Abstract The apparent diffusion tensor (ADT) imaging method was extended to account for multiple components. A biexponential ADT experiment used obtain separate images of rapidly and slowly diffusing water fractions in excised rat spinal cord. fast slow component tensors were compared found exhibit similar gross features, such as fractional anisotropy, both white gray matter. However, there also some important differences, which are consistent with the different structures occupying...
We present in vivo images of the human brain acquired with an ultralow field MRI (ULFMRI) system operating at a magnetic B0 ~ 130 μT. The features prepolarization proton spins Bp 80 mT and detection NMR signals superconducting, second-derivative gradiometer inductively coupled to superconducting quantum interference device (SQUID). report measurements longitudinal relaxation time T1 tissue, blood, scalp fat Bp, cerebrospinal fluid B0. use these values construct inversion recovery sequences...
Arterial spin labeling and phase contrast magnetic resonance imaging provide independent non-invasive methods for measuring cerebral blood flow. We compared global flow measurements obtained using pseudo-continuous arterial in 436 middle-aged subjects acquired at two sites the NHLBI CARDIA multisite study. Cerebral measured by (CBF PC : 55.76 ± 12.05 ml/100 g/min) was systematically higher ( p < 0.001) more variable than PCASL 47.70 9.75). The correlation between values from modalities...
Cerebrospinal fluid (CSF) movement through the pathways within central nervous system is of high significance for maintaining normal brain health and function. Low frequency hemodynamics respiration have been shown to drive CSF in humans independently. Here, we hypothesize that may be driven simultaneously (and synchrony) by both mechanisms study their independent coupled effects on using novel neck fMRI scans. Caudad at fourth ventricle major blood vessels (internal carotid arteries...
Non-invasive brain stimulation (NIBS) provides a method for safely perturbing activity, and has been employed in basic research to test hypotheses concerning brainbehavior relationships with increasing translational applications. We introduce evaluate novel subthreshold NIBS method: kilohertz transcranial magnetic perturbation (kTMP). kTMP is induction that delivers continuous kHz-frequency cortical electric fields (E-fields) which may be amplitude-modulated potentially mimic electrical...
Transcranial Magnetic Stimulation (TMS) allows for the direct activation of neurons in human neocortex and has proven to be fundamental causal hypothesis testing cognitive neuroscience. By administering TMS concurrently with functional Resonance Imaging (fMRI), effect cortical on activity distant subcortical structures can quantified by varying levels output intensity. However, generates significant fluctuations fMRI time series, their complex interaction warrants caution before interpreting...
Abstract An inductively coupled, chronically implanted short‐solenoid coil was used to obtain in vivo localized 1 H NMR spectra and diffusion‐weighted images from a rat spinal cord. A 5 × 8 mm two‐turn elliptically shaped solenoid rats at the site of T‐12 vertebral‐level laminectomy. Excitation achieved solely by 3 cm external surface coil, signal detection coupling coil. The image signal‐to‐noise ratio (SNR) obtained with inductively‐coupled compared that using linear or quadrature provided...
Background The locus coeruleus (LC) produces catecholamines (norepinephrine and dopamine) is implicated in a broad range of cognitive functions including attention executive function. Recent advancements magnetic resonance imaging (MRI) approaches allow for the visualization quantification LC structure. Human research focused on has since exploded given LC’s role cognition relevance to current models psychopathology neurodegenerative disease. However, it unclear what extent structure...
Non-invasive brain stimulation (NIBS) provides a method for safely perturbing activity, and has been employed in basic research to test hypotheses concerning brain-behavior relationships with increasing translational applications.We introduce evaluate novel subthreshold NIBS method: kilohertz transcranial magnetic perturbation (kTMP). KTMP is induction that delivers continuous kHz-frequency cortical electric fields which may be amplitude-modulated potentially mimic electrical activity at...
Background Increased blood-brain barrier permeability (BBBp) has been hypothesized as a feature of aging that may lead to the development Alzheimer’s disease (AD). We sought identify brain regions most vulnerable greater BBBp during and examine their regional relationship with neuroimaging biomarkers AD. Methods studied 31 cognitively normal older adults (OA) 10 young (YA) from Berkeley Aging Cohort Study (BACS). Both OA YA received dynamic contrast-enhanced MRI (DCE-MRI) quantify K trans...
Abstract Purpose: To evaluate a novel soft, lightweight cushion that can match the magnetic susceptibility of human tissue. The difference between air and tissue produces field inhomogeneities in B 0 field, which leads to artifacts resonance imaging (MRI) studies. Materials Methods: Pyrolytic graphite (PG) microparticles were uniformly embedded into foam reduce or eliminate at accessible interfaces. 3T MR images maps an air/water/PG phantom acquired. Q measurements on 4T tuned head coil...
Radiation dose estimates to the trabecular region of skeleton are primary importance due recent advancements in nuclear medicine. Establishing methods for accurately calculating these regions is difficult complex microstructure this anatomic site and typical ranges beta‐particles both bone marrow tissues. At present time, models skeletal dosimetry used clinical medicine rely upon measured distributions straight‐line path lengths (chord lengths) through regions. This work develops a new...
I present a checklist of acquisition parameters for inclusion in the methods section an fMRI paper. The current list expands and updates that was given 2008 paper from Poldrack et al. (I have reproduced below on appeared paper.) emphasis is experiments use 1.5 to 3 T scanners with standard hardware available today, but should work reasonably well 7 as well. further assume performed 2D multi-slice EPI or spiral scanning uses BOLD contrast, parameter reporting 3D sequences other k-space...
We report the first application of diffusion tractography to a mysticete, which was analyzed alongside three odontocete brains, allowing direct comparison strength and laterality auditory pathways in echolocating non-echolocating whales. Brains were imaged post-mortem at high resolution with specialized steady state free precession sequence optimized for dead tissue. conducted probabilistic compare qualitative features, tract strength, lateralization potential ascending descending paths...