Methods for investigating brain function

Question 1

What does EEG stand for?

Answer 1

Electroencephalograph

Question 2

What does CT stand for?

Answer 2

computed tomography

Question 3

What does CAT stand for?

Answer 3

computerised axial tomography

Question 4

What does MRI stand for?

Answer 4

magnetic resonance imaging

Question 5

What does fMRI stand for?

Answer 5

functional magnetic resonance imaging

Question 6

What does PET stand for?

Answer 6

positron emission tomography

Question 7

Measurement type of EEG

Answer 7

External recording

Does not use imaging techniques

Question 8

Measurement type of CT or CAT

Answer 8

Static imaging, i.e. producing still pictures

Question 9

Measurement type of MRI

Answer 9

Static imaging, i.e. producing still pictures

Question 10

Measurement type of fMRI?

Answer 10

Dynamic imaging

Produces colour images of brain structure, activity and function

Question 11

What type of image is PET scan?

Answer 11

Dynamic imaging

Produces colour images of brain structure, activity and function

Question 12

Method for EEG

Answer 12

Electrodes on scalp detect & amplify electrical activity in brain
Recorded as series of peaks and troughs on chart

Question 13

Method for CT/CAT

Answer 13

X-Ray scans brain at different angles

Info sent to computer, leading to cross-sectional pictures of ‘slices’ through brain

Question 14

Method for MRI

Answer 14

Uses strong magnetic field, radiofrequency pulses, computers to produce 3D images from which 2D slices can be displayed

Question 15

Method for fMRI

Answer 15

Most recent form of MRI. Measures brain activity based on neuron’s oxygen consumption
Increased oxygen = increased activity, shown in colour variations

Question 16

Method for PET

Answer 16

Scans provide images of brain by tracking glucose solution containing short lived radioactive tracker
Based on glucose consumption in brain, indicated by colour variations

Question 17

Use of CT/CAT

Answer 17

Aid in detection of tumours, strokes, other injuries
Can help finding out reasons in things like changed behaviour and personality
Can detect areas of brain that may have shrunk (atrophied) due to e.g. Alzheimer’s disease

Question 18

Limitation/s of CT/CAT

Answer 18

Images only show brain structure

Images of inferior quality to those from MRI

Question 19

Use/s of EEG

Answer 19

Investigates activity in whole brain
Has been used to study different states of consciousness e.g. awake, sleeping, dreaming
Different patterns can also indicate epilepsy tumours

Question 20

Limitation/s of EEG

Answer 20

Doesn’t produce images and cannot detect info from deep in brain
Not good at pinpointing area of brain that is source of brainwave activity

Question 21

Use/s of MRI

Answer 21

Used in detection of tumours and other abnormalities

Question 22

Limitation/s of MRI

Answer 22

Cannot be used if patient’s body contains magnetic objects (e.g. pacemakers)

Question 23

Use/s of fMRI

Answer 23

Enables observation and measurement of changes in brain during activity
Scans can be made rapidly
Good spatial resolution and are non-invasive, do not expose patient to radioactive tracers
Less expensive than PET

Question 24

Use/s of PET

Answer 24

Used in research to show specific brain areas activated during activities such as reading, speaking, thinking
Does not provide image of health level of brain, but problems (e.g. epilepsy, blood clots, can be identified by comparing to brains of healthy people)

Question 25

Limitation/s of PET

Answer 25

Not as detailed as those from fMRI

More expensive than fMRI