Diffusion MRI

Question 1

The ability of molecules to move across available space is known as:

Answer 1

Diffusion

Question 2

Mean diffusivity refers to:

Answer 2

The overall diffusion

Question 3

A brain imaging technique responsible for “tracing” the location & direction of white matter is:

Answer 3

Tractography

Question 4

What allows for distinction between healthy & unhealthy white brain matter in older individuals?

Answer 4

White matter integrity

Question 5

The dense, white matter that connects both hemispheres of the brain is called the _____ _____:

Answer 5

Corpus callosum

Question 6

_____ are the “communicators” of the brain

Answer 6

Neurons

Question 7

Neurons are made up of which 4 properties?

Answer 7

Axons, axon terminals, cell bodies & dendrites

Question 8

Magnetic resonance imaging (MRI) helps identify ____ ____ in the brain:

Answer 8

Neural activity

Question 9

Diffusion MRI’s can measure axon size & density & individual fibres. True or false?

Answer 9

False - they are unable to measure any of those

Question 10

Diffusion MRI can be beneficial for providing information about axonal directions in white matter, microstructure (in voxels) & white matter integrity. True or false?

Answer 10

True

Question 11

Yang et al. (2017) investigated what in subjects with & without trigeminal neuralgia?

Answer 11

White matter integrity

Question 12

One limitation of using diffusion MRI is that they are sensitive to:

Answer 12

Fast imaging artefacts

Question 13

It is difficult for diffusion MRI to deal with crossing/”kissing” fibres, and more restricted by scanner hardware. True or false?

Answer 13

True

Question 14

Which 2 techniques are complimentary to diffusion MRI?

Answer 14

Tracer studies, histology

Question 15

In which neuroimaging technique is dye injected into neurons to allow for finer details to be seen?

Answer 15

Tracer studies

Question 16

____ refers to the relationship between two variables:

Answer 16

Correlation

Question 17

____ refers to one variable causing changes in another:

Answer 17

Causation

Question 18

One difference between structural & diffusion MRI is that structural MRI has a resolution of ____ mm, whereas diffusion MRI has a resolution of ____mm:

Answer 18

1; 1-3

Question 19

Structural MRI is able to segregate _____ matter, ____ matter and ______ ____:

Answer 19

white; grey; cerebrospinal fluid

Question 20

Structural MRI takes longer to acquire images than diffusion MRI. True or false?

Answer 20

True

Question 21

Name the key properties of diffusion MRI:

Answer 21

Distorted images, several images able to be taken at once, lower resolution

Question 22

Diffusion MRI takes less time, but produces more distorted images. True or false?

Answer 22

True

Question 23

There is no principle diffusion direction in _____ matter, thus diffusion MRI is mostly used when looking at ____ matter:

Answer 23

Grey; white

Question 24

Diffusion MRI can provide a _____, ______ and _____ view of the corpus callosum:

Answer 24

Dorsal; sagittal; coronal

Question 25

True or false: the ability of molecules to diffuse is constrained by boundaries and depends on the direction upon which they are travelling:

Answer 25

True

Question 26

Water is best at diffusing ____ axons, but not _____:

Answer 26

Along; sideways

Question 27

Diffusion MRI can be used to study various brain disorders, by generating contrast in the movement (diffusion) of water in _____ matter and telling us which direction the _____ are going:

Answer 27

White; axons