Speech Science Chapter 13

T/F  Computerized Tomography (CT) is an x-ray technique that is sensitive to the density of tissues.

When looking at a CT image, the lighter the image, the ________ (more or less) dense the tissue is.

T/F  CT scans give three-dimensional images of cross sections of selected thicknesses of cortical and subcortical regions of the brain.

Name 2 advantages of CT scanning.

List 4 things CT scans can diagnose.

T/F  CT scans are not able to detect calcification and hemorrhages.

This type of brain imaging takes advantage of the cellular basis of human tissue.

What percentage of the brain tissue is composed of water?

MRIs look at __________ atoms to gather data.

The differences in __________ and __________ content of different brain tissues produce the contrasts seen on an MRI.

T/F  MRI uses radiation.

MRI can differentiate between different tissue types. List 3.

T/F MRI takes less time to perform than a CT scan.

Not everybody can undergo an MRI. What are some limitations that would prevent a person from having an MRI?

T/F  fMRI and MRI are based on the same magnetic properties of hydrogen.

fMRI can look at characteristics of ____________ within the brain.

Increase in blood flow to a specific area is known as the ____________________ and it is this response that is measured in an fMRI.

T/F  The fMRI is an indirect measure of brain function because it measures blood flow, not neuronal function.

Name a major advantage of fMRI.

T/F  An MRI and a fMRI scans can be obtained at the same time allowing structural and functional information to be gathered simultaneously.

Name some disadvantages of fMRI.

This type of test is based on identifying the distribution of an injected or inhaled radioactive substance and a chemical (such as glucose) in a patient's brain.

What is the radioactive substance used in a PET scan called?

List 4 commonly used tracers in PET scans.

In a PET scan, areas of the brain that are more active absorb _____ (more or less) of the tracer and areas that are less active absorb _____ (more or less) of the tracer.

In index of regional cerebral blood flow (rCBF) is produced with which of the following scans?
A) MRI
B) fMRI
C) CT
D) PET

T/F  PET scans are useful in determining tissue abnormalities like tumors, and can assess whether they are benign or malignant.

How quickly can a PET scan scan the entire brain?

List some of the disadvantages of PET scans.

SPECT (single photon emission computerized tomography) is similar to which other test?

The major disadvantage of SPECT over PET is that it uses __________________ because the isotopes have longer half-lives.

_______ is a technique used to record electrical potentials generated by the brain.

Current EEG techniques use computers to obtain and analyze data to allow for accurate quantification of information. What are these techniques known as?

This type of EEG is used to measure brain electrical activity in response to some kind of stimulus or task and are measured in terms of their latency and polarity.

qEEGs record brain activity by placing electrodes on what part of the body?

Which neurological disease results from a lack of dopamine in the substantia nigra of the basal nuclei?

What are the 3 major characteristics of PD?

Which brain imaging technique is useful in determining PD?

Which disease is progressive, affecting both the upper and lower motor neurons?

Which 2 tests are good for monitoring patients with MS?

Which disease is a progressive disease and has dementia as its hallmark?

Which type of scan is good for identifying people who are at risk for AD?