Vertigo in and around magnetic resonance imaging (MRI) machines has been noted for years [1, 2]. Several mechanisms have been suggested to explain these sensations [3, 4], yet without direct, objective measures, the cause is unknown. We found that all of our healthy human subjects developed a robust nystagmus while simply lying in the static magnetic field of an MRI machine. Patients lacking labyrinthine function did not. We use the pattern of eye movements as a measure of vestibular stimulation to show that the stimulation is static (continuous, proportional to static magnetic field strength, requiring neither head movement nor dynamic change in magnetic field strength) and directional (sensitive to magnetic field polarity and head orientation). Our calculations and geometric model suggest that magnetic vestibular stimulation (MVS) derives from a Lorentz force resulting from interaction between the magnetic field and naturally occurring ionic currents in the labyrinthine endolymph fluid. This force pushes on the semicircular canal cupula, leading to nystagmus. We emphasize that the unique, dual role of endolymph in the delivery of both ionic current and fluid pressure, coupled with the cupula's function as a pressure sensor, makes magnetic-field-induced nystagmus and vertigo possible. Such effects could confound functional MRI studies of brain behavior, including resting-state brain activity.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3379966 | PMC |
| http://dx.doi.org/10.1016/j.cub.2011.08.029 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
A clinical practical model for preoperative prediction of visual outcome for pituitary adenoma patients in a retrospective and prospective study.
Front Endocrinol (Lausanne)
December 2024
Department of Neurosurgery, Binhai Branch of Nation al Regional Medical Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou, Fujian, China.
Objective: Preoperative prediction of visual recovery after pituitary adenoma resection surgery remains challenging. This study aimed to investigate the value of clinical and radiological features in preoperatively predicting visual outcomes after surgery.
Methods: Patients undergoing endoscopic transsphenoidal surgery (ETS) for pituitary adenoma were included in this retrospective and prospective study.
Unveiling neuroimmunology profile of immunological non-responders in HIV: a multimodal MRI approach.
Front Immunol
December 2024
Center for Infectious Diseases, Beijing Youan Hospital, Capital Medical University, Beijing, China.
Background: People living with HIV (PLWH), especially immunological non-responders (INRs), may experience adverse neurologic events. However, the extent of neurological impairment in INRs remains uncertain. This study evaluates brain structure and function, immune dysregulation, and peripheral immunomarkers in INRs and immunological responders (IRs) among PLWH, classified according to immunological response criteria, within a clinical research setting.
View Article and Find Full Text PDFContrasting topologies of synchronous and asynchronous functional brain networks.
Netw Neurosci
December 2024
Laboratory for Complex Brain Networks, Wake Forest School of Medicine, Winston-Salem, NC, USA.
We generated asynchronous functional networks (aFNs) using a novel method called optimal causation entropy and compared aFN topology with the correlation-based synchronous functional networks (sFNs), which are commonly used in network neuroscience studies. Functional magnetic resonance imaging (fMRI) time series from 212 participants of the National Consortium on Alcohol and Neurodevelopment in Adolescence study were used to generate aFNs and sFNs. As a demonstration of how aFNs and sFNs can be used in tandem, we used multivariate mixed effects models to determine whether age interacted with node efficiency to influence connection probabilities in the two networks.
View Article and Find Full Text PDFSpectroscopic Signatures of Phonon Character in Molecular Electron Spin Relaxation.
ACS Cent Sci
December 2024
Division of Chemistry and Chemical Engineering, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125, United States.
Spin-lattice relaxation constitutes a key challenge for the development of quantum technologies, as it destroys superpositions in molecular quantum bits (qubits) and magnetic memory in single molecule magnets (SMMs). Gaining mechanistic insight into the spin relaxation process has proven challenging owing to a lack of spectroscopic observables and contradictions among theoretical models. Here, we use pulse electron paramagnetic resonance (EPR) to profile changes in spin relaxation rates ( ) as a function of both temperature and magnetic field orientation, forming a two-dimensional data matrix.
View Article and Find Full Text PDFLayer-by-layer assembled film can serve as an enhanced reaction environment for Diels-Alder reaction.
Front Chem
December 2024
Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), Tsukuba, Japan.
Although the Diels-Alder reaction (DA) has garnered significant attention due to its numerous advantages, its long reaction time is a drawback. Herein, we investigated the effects of polarity difference on DA using Layer-by-Layer (LbL) films comprising polycationic polyallylamine hydrochloride and polyanionic poly (styrenesulfonic acid-co-furfuryl methacrylate) [poly (SS--FMA)] as the reaction environment. First, furan composition in poly (SS--FMA) was adjusted to be 19 mol% to achieve good water solubility and layer deposition.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!