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BOLD and is
In functional neuroimaging, the response measure is usually BOLD contrast.
Olivia's school system is partnered with Bird Island and Lake Lillian and operates under the name BOLD Schools ( Bird Island, Olivia, Lake Lillian District ).
The school mascot is the BOLD Warrior.
The physiological blood-flow response largely decides the temporal sensitivity, that is how well we can measure when neurons are active, in BOLD fMRI.
When a person performs two tasks simultaneously or in overlapping fashion, the BOLD response is expected to add linearly.
Researchers have checked the BOLD signal against both signals from implanted electrodes ( mostly in monkeys ) and signals of field potentials ( that is the electric or magnetic field from the brain's activity, measured outside the skull ) from EEG and MEG.
However, the BOLD signal cannot separate feedback and feedforward active networks in a region ; the slowness of the vascular response means the final signal is the summed version of the whole region's network ; blood flow is not in spurts as the processing proceeds.
The BOLD signature of activation is relatively weak, however, so other sources of noise in the acquired data must be carefully controlled.
BOLD contrast depends on blood flow, which is both slowly changing and subject to noisy influences.
Jefferson and his family controlled one of the most sophisticated and effective get-out-the-vote organizations in South Louisiana – the Progressive Democrats – the foil to which is the Black Organization for Leadership Development ( BOLD ), founded by Jefferson nemeses Ken Carter and Jim Singleton.
The Biological Oxidant and Life Detection ( BOLD ) is a proposed Mars mission that would follow up the Viking soil tests by using several small impact landers.
The Barcode of Life Data Systems ( BOLD ) is also located at the University of Guelph.

BOLD and contrast
The primary form of fMRI uses the blood-oxygen-level-dependent ( BOLD ) contrast, discovered by Seiji Ogawa.
Three studies in 1992 were the first to explore using the BOLD contrast in humans.
So the BOLD contrast reflects mainly the inputs to a neuron and the neuron's integrative processing within its body, and less the output firing of neurons.
Fitting a human requires larger-bore scanners, which make higher fields strengths harder to achieve, especially if the field has to be uniform ; it also requires either internal contrast such as BOLD or a non-toxic external contrast agent unlike iron oxide.

BOLD and by
Activation locations detected by BOLD fMRI in cortical areas ( brain surface regions ) are known to tally with CBF-based functional maps from PET scans.
The BOLD response can also be affected by a variety of factors, including disease, sedation, anxiety, medications that dilate blood vessels, and attention ( neuromodulation ).
* Bandoh H, Kida I, Ueda H ( 2010 ) " Olfactory Responses to Natal Stream Water in Sockeye Salmon by BOLD fMRI " PLoS ONE, 6 ( 1 ): e16051.
contributed by making their research available to the public, most notably SIS from University of California, Berkeley, RASP from University of California, Los Angeles and BOLD from University of Colorado, Boulder.

BOLD and Ogawa
Ogawa and others conducted the study using a higher field ( 4. 0 T ) and showed that the BOLD signal depended on T2 * loss of magnetization.

BOLD and .
Similarly, fMRI studies typically report increases in blood oxygenation level dependent ( BOLD ) responses in the dorsal striatum during anticipation of either primary ( O ' Doherty et al., 2002 ) or secondary ( Knutson et al., 2001 ) rewards, much like the ventral striatum.
( Player currently on the Red Sox in BOLD, players formerly on the Red Sox in italics.
Newer methods which improve both spatial and time resolution are being researched, and these largely use biomarkers other than the BOLD signal.
This affects BOLD sensitivity.
After activity stops, the BOLD signal falls below the original level, the baseline, a phenomenon called the undershoot.
The local field potential, which includes both post-neuron-synaptic activity and internal neuron processing, better predicts the BOLD signal.
Some regions just a few millimeters in size, such as the lateral geniculate nucleus ( LGN ) of the thalamus, which relays what we see from the eye to the visual cortex, have been shown to generate the BOLD signal correctly when presented with visual input.
Nearby regions such as the pulvinar nucleus were not stimulated for this task, indicating millimeter resolution for the spatial extent of the BOLD response, at least in thalamic nuclei.
In the rat brain, single-whisker touch has been shown to elicit BOLD signals from the somatosensory cortex.
Also, both inhibitory and excitatory input to a neuron from other neurons sum and contribute to the BOLD signal.
The amplitude of the BOLD signal does not necessarily affect its shape.
The BOLD response across brain regions cannot be compared directly even for the same task, since the density of neurons and the blood-supply characteristics are not constant across the brain.

is and MRI
* Magnetic resonance imaging ( MRI ) MRI is a method of imaging objects that uses a strong magnetic field to detect the relaxation of protons that have been perturbed by a radio-frequency pulse.
MRI is more sensitive than CT in the diagnosis of AVMs and provides better information about the exact location of the malformation.
If a CT is used in conjunction of dye this is called a computerized tomography angiogram while if MRI is used it is called magnetic resonance angiogram.
MRI and fMRI scans have shown that the amygdala in individuals diagnosed with such disorders including bipolar or panic disorder is larger and wired for a higher level of fear.
Helium is used in cryogenics ( its largest single use, absorbing about a quarter of production ), particularly in the cooling of superconducting magnets, with the main commercial application being in MRI scanners.
MRI of the cranium and orbits is also performed to exclude compressive and inflammatory lesions of the cranial nerves and ocular muscles.
Magnetic resonance imaging ( MRI ), nuclear magnetic resonance imaging ( NMRI ), or magnetic resonance tomography ( MRT ) is a medical imaging technique used in radiology to visualize internal structures of the body in detail.
An MRI scanner is a device in which the patient lies within a large, powerful magnet where the magnetic field is used to align the magnetization of some atomic nuclei in the body, and radio frequency fields to systematically alter the alignment of this magnetization.
By changing the settings on the scanner, this effect is used to create contrast between different types of body tissue or between other properties, as in fMRI and diffusion MRI.
Unlike CT, MRI uses no ionizing radiation and is generally a very safe procedure.
MRI is used to image every part of the body, and is particularly useful for tissues with many hydrogen nuclei and little density contrast, such as the brain, muscle, connective tissue and most tumors.
Because the magnetic field is " tuned " by the second magnet, a PMRI scan can be obtained immediately adjacent to a metal prosthetic, unlike an MRI scan.
Although MRI is most commonly performed at 1. 5T, higher fields ( such as 3T ) are gaining more popularity due to the increased sensitivity and resolution.
In clinical practice, MRI is used to distinguish pathologic tissue ( such as a brain tumor ) from normal tissue.
One advantage of an MRI scan is that it is harmless to the patient.
The basis of this ability is the complex library of pulse sequences that the modern medical MRI scanner includes, each of which is optimized to provide image contrast based on the chemical sensitivity of MRI.

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