College 4 Reseach methods

Question 1

Near infrared spectroscopy NIRS

Answer 1

Metabolic

• non invasive
• gathers light transmittedthrough cortical tissue to image blood-oxygen consumtpion
• measure the same as fMRI
• relies on tight coupling between changes in cerebral activity and blood-oxygenation
• can be used in infants, robust against movements
• not able to study deep structures

Question 2

fMRI

Answer 2

Metabolic
When the brain is active, it needs oxygen, oxygen is brought by blood from the lungs. After neural activity, overflow of oxygen rich blood, which alters magnetic properties
-High SPATIAL resolution
- low temporal resolution
- expensive
- very sensitive to movement
- BOLD: Blood Oxygens Leven Dependant

Question 3

Metabolisme

Answer 3

Chemical proces
necessary for the maintenance of life
Oxygen and glucose consumption

Question 4

Positron Emission Tomography PET

Answer 4

Metabolic
Scans are averaged
- detects changes in blood flow by measuring change in oxygen levels
Radioactive molecules injected into bloodstream
Allows mapping of a wide range of brain changes and conditions

Can detect dementia
can study cognitive function
Occipital region, when someone is looking at something, this region has increased blood flow

-very expensive

Question 5

Drug manipulation

Answer 5

Manipulated neurotransmitters and brain function

Influence activity of neurons in specific regions

Question 6

Event related potentials ERP’s

Answer 6

Electrical activity
Waves related in time to specific sensory event
Stimuli is presented repeatedly
The scans are AVERAGED
Can see: auditory discrimination and mismatch negativity
Gives precise information about wheter and how process developst over time
Is also possible to do with a passive task
Non invasive, low cost

Question 7

Magnetoencephalography MEG

Answer 7

Electrical activity
Neural activity, electrical field, magnetic field
Measuered naturally generated field
Detectors placed on the outside of the skull
Has a high SPATIAL resolution
High cost

Question 8

Electroencephalography EEG

Answer 8

Electrical activity
Electrodes are placed on the scalp with the use of an EEG cap
EEG changes as behavior changes
Rhythmical array of patterns
Neuroactivity
lower and less frequent waves is sleep/coma
high frequency and higher amplitude is awake

Question 9

Transcranial Magnetic Stimulation TMS

Answer 9

Magnetic coil (spoel) is places on the skull –> stimulates underlying brain region
Disrupts neural function
Induces behavior or disrupts ongoing behavior
Advantages:
can temporaly stop activity in the brain, information about time and location, safe and non invasive, can be used on healthy individuals
Disadvantages:
only short effect, only on cortex areas, can not reach deep structures

Question 10

Megnetic Resonance imaging MRI

Answer 10

Brain region 
Gives a static 3D brain image
Has a strong magnetic field
Can see the difference between white and grey matter
High SPATIAL resolution

Question 11

Computarised Tomography CT

Answer 11

Brain region information
Is an x-ray through the brain at different angles to give many different images –> images are combined to get one 3D image
Difference between grey and white matter NOT visible
Lesions are visible