What are some strengths of fMRI as a tool?
The popularity of fMRI derives from its widespread availability (can be performed on a clinical 1.5T scanner), non-invasive nature (does not require injection of a radioisotope or other pharmacologic agent), relatively low cost, and good spatial resolution.
What is a disadvantage of using fMRI technique?
fMRI is expensive compared to other techniques and can only capture a clear image if the person stays still. Poor temporal resolution because of a 5-second lag between initial neural activity and image. May not truly represent moment-to-moment brain activity.
Which of the following is a disadvantage of using functional MRI fMRI to study brain dynamics?
One of the drawbacks of this technique is the limited spatial resolution of fMRI. Blood oxygen levels are very regional compared to multi-unit activity (MUA); and as a consequence, image signal is very low compared to statistical noise.
What are the pros and cons of fMRI scans?
It is non-invasive and does not involve radiation. It produces excellent high-resolution images….There are certain disadvantages of fMRI which include,
- It is expensive compared to other scans.
- The patient has to stay still to capture clear images.
- Patient’s movements can affect the quality of images.
How accurate is fMRI?
Results: fMRI showed a maximum mapping accuracy at 5 mm for both motor and language mapping. MEG showed a maximum mapping accuracy at 40 mm for motor and 15 mm for language mapping.
Why are fMRI scans good?
This means that brain activity can be picked up by the MRI scanner because of tiny chemical changes in the blood. This particular type of scan can be extremely useful when planning brain surgery as the areas of the brain used for important functions such as language, memory and movement can be identified beforehand.
Which of the following is a limitation of the fMRI quizlet?
One limitation of fMRI is that, because it measures changes in blood flow in the brain, it is not a direct measure of neural activity in particular brain areas. – This means that it is not a truly quantitative measure of mental activity in these brain areas.
How reliable is fMRI?
Although reliability and validity reports for fMRI are generally quite favorable, significant variability was found across studies with respect to methodology, preventing in some cases either the assessment of the reliability of individual datasets, or cross-study comparisons.
What are the limitations of MRI?
Disadvantages of MRI
- Claustrophobia and sometimes difficulty fitting within the MRI scanner because it is a small, enclosed space.
- The effects of the magnetic field on metal devices implanted in the body.
- Reactions to the contrast agent.
Can fMRI detect lies?
Using this approach, they reported high accuracy in distinguishing a lie from the truth. Whether applied to single events (i.e., a single button-press response) or to all the data from a single subject, the sensitivity for detection of lying was around 90 percent, and the specificity was around 86 percent.
Is fMRI harmful?
An fMRI is safe, painless, and noninvasive. There are no known health risks associated with the procedure, as long as the patient has no metal or electronic implants (because the MRI machine has a very powerful magnet).
Which of the following is a limitation of the fMRI?
Yet fMRI also has its disadvantages. First, it’s expensive. Second, it can only capture a clear image if the person being scanned stays completely still. And third, researchers still don’t completely understand how it works.
Which of the following is a major advantage of the fMRI quizlet?
The major advantage of fMRI over PET is that: fMRI allows for the measurement of brain activity on a much shorter time scale.
What is the strengths of an MRI scan?
MRI provides better soft tissue contrast than CT and can differentiate better between fat, water, muscle, and other soft tissue than CT (CT is usually better at imaging bones). These images provide information to physicians and can be useful in diagnosing a wide variety of diseases and conditions.
What are the two major disadvantages of MRI scans?
Drawbacks of MRI scans include their much higher cost, and patient discomfort with the procedure. The MRI scanner subjects the patient to such powerful electromagnets that the scan room must be shielded.
How does fMRI detect deception?
An fMRI machine tracks blood flow to activated brain areas. The assumption in lie detection is that the brain must exert extra effort when telling a lie and that the regions that do more work get more blood.