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This field representation is in this theory argued to integrate parts into a whole that has meaning, so a face is not seen as a random collection of features, but as somebody's face. The integration of information in the field is also suggested to resolve the binding/combination problem. In 2013, McFadden published two updates to the theory.
The magnetic field of larger magnets can be obtained by modeling them as a collection of a large number of small magnets called dipoles each having their own m. The magnetic field produced by the magnet then is the net magnetic field of these dipoles; any net force on the magnet is a result of adding up the forces on the individual dipoles.
The brain's magnetic field, measuring at 10 femto tesla (fT) for cortical activity and 10 3 fT for the human alpha rhythm, is considerably smaller than the ambient magnetic noise in an urban environment, which is on the order of 10 8 fT or 0.1 μT. The essential problem of biomagnetism is, thus, the weakness of the signal relative to the ...
Transcranial magnetic stimulation (TMS) is a noninvasive neurotherapy, a form of brain stimulation in which a changing magnetic field is used to induce an electric current at a specific area of the brain through electromagnetic induction. An electric pulse generator, or stimulator, is connected to a magnetic coil connected to the scalp. The ...
Compass needles in the Northern Hemisphere point toward the magnetic North Pole, although the exact location of it changes from time to time as the contours of Earth’s magnetic field also change.
Hence, it distorts the surrounding magnetic field induced by an MRI scanner, causing the nuclei there to lose magnetization faster via the T 2 * decay. Thus MR pulse sequences sensitive to T 2 * show more MR signal where blood is highly oxygenated and less where it is not. This effect increases with the square of the strength of the magnetic field.
Structural magnetic resonance imaging (structural MRI) of a head, from top to base of the skull. The first chapter of the history of neuroimaging traces back to the Italian neuroscientist Angelo Mosso who invented the 'human circulation balance', which could non-invasively measure the redistribution of blood during emotional and intellectual activity.
Similarly, if only the magnetic field (B) is non-zero and is constant in time, the field is said to be a magnetostatic field. However, if either the electric or magnetic field has a time-dependence, then both fields must be considered together as a coupled electromagnetic field using Maxwell's equations. [9]