✦ LIBER ✦

Directly mapping magnetic field effects of neuronal activity by magnetic resonance imaging

✍ Scribed by Jinhu Xiong; Peter T. Fox; Jia-Hong Gao

Publisher: John Wiley and Sons
Year: 2003
Tongue: English
Weight: 536 KB
Volume: 20
Category: Article
ISSN: 1065-9471
DOI: 10.1002/hbm.10124

No coin nor oath required. For personal study only.

✦ Synopsis

Magnetic resonance imaging (MRI) of brain functional activity relies principally on changes in cerebral hemodynamics, which are more spatially and temporally distributed than the underlying neuronal activity changes. We present a novel MRI technique for mapping brain functional activity by directly detecting magnetic fields induced by neuronal firing. Using a well-established visuomotor paradigm, the locations and latencies of activations in visual, motor, and premotor cortices were imaged at a temporal resolution of 100 msec and a spatial resolution of 3 mm, and were found to be in consistent with the electrophysiological and functional MRI (fMRI) literature. Signal strength was comparable to traditional event-related fMRI methods: about 1% of the baseline signal. The magnetic-source MRI technique greatly increases the temporal accuracy in detecting neuronal activity, providing a powerful new tool for mapping brain functional organization in human and animals.

📜 SIMILAR VOLUMES

Mapping of Turbulent Intensity by Magnet

Mapping of Turbulent Intensity by Magnetic Resonance Imaging

✍ J.C. Gatenby; J.C. Gore 📂 Article 📅 1994 🏛 Elsevier Science 🌐 English ⚖ 946 KB

The signal produced by turbulent flow in NMR pulse sequences has been analyzed by considering the effects of variations in fluid velocity on the net signal phase variance. It is shown that in a bipolar field gradient, the signal is dependent on the gradient amplitude and the precise time dependence

Mixture model mapping of brain activatio

Mixture model mapping of brain activation in functional magnetic resonance images

✍ Brian S. Everitt; Edward T. Bullmore 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 393 KB 👁 3 views

We report on a novel method of identifying brain regions activated by periodic experimental design in functional magnetic resonance imaging data. This involves fitting a mixture distribution with two components to a test statistic estimated at each voxel in an image. The two parameters of this distr

Lack of mutagenic and co-mutagenic effec

Lack of mutagenic and co-mutagenic effects of magnetic fields during magnetic resonance imaging

✍ Wolfgang G. Schreiber; Elke M. Teichmann; Ilka Schiffer; Jochem Hast; Wahida Akb 📂 Article 📅 2001 🏛 John Wiley and Sons 🌐 English ⚖ 155 KB 👁 1 views

## Abstract Mutagenic and co‐mutagenic effects of static, pulsed bipolar gradient, and high‐frequency magnetic fields, as well as combinations of them, were examined using the Ames test. The Ames test using __Salmonella typhimurium__ bacteria, wild‐type strain RTA, preincubation assay, without meta

Spatial and temporal mapping of water in

Spatial and temporal mapping of water in soil by magnetic resonance imaging

✍ M. H. G. Amin; R. J. Chorley; K. S. Richards; B. W. Bache; L. D. Hall; T. A. Car 📂 Article 📅 1993 🏛 John Wiley and Sons 🌐 English ⚖ 633 KB

Experiments on model and real soil blocks designed to assess the feasibility of using magnetic resonance imaging for three-dimensional mapping of the time-varying spatial distribution of water in structured soils are reported. The results show that, notwithstanding inherent problems in imaging natur

Effects of strong static magnetic fields

Effects of strong static magnetic fields used in magnetic resonance imaging on insulin-secreting cells

✍ Tomonori Sakurai; Shingo Terashima; Junji Miyakoshi 📂 Article 📅 2009 🏛 John Wiley and Sons 🌐 English ⚖ 140 KB 👁 3 views

## Abstract The magnetic flux density of MRI for clinical diagnosis has been steadily increasing. However, there remains very little biological data regarding the effect of strong static magnetic fields (SMFs) on human health. To evaluate the effects of strong SMFs on biological systems, we culture

Recording of electrical brain activity i

Recording of electrical brain activity in a magnetic resonance environment: Distorting effects of the static magnetic field

✍ René M. Müri; Jacques Felblinger; Kai M. Rösier; Bruno Jung; Christian W. Hess; 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 494 KB

The technical limitations of electroencephalography (EEG) and flashed visually-evoked potentials (VEP) recordings in the static magnetic field of the MR system were systematically studied. A main artifact occurring in the magnetic field was found to be correlated with the heart cycle and had amplitu