case 4

Question 1

What is neuroimaging?

Answer 1

Visualizing brain structure and/or brain activity. Brain activity is important because it is helpful to find the link between cognitive function and brain function.

Question 2

To understand how brain processes result in cognitive behaviour, we investigate:

Answer 2

To understand how brain processes result in cognitive behaviour, we investigate:
- Which brain areas are active  location of cognitive process
- When brain areas are active  timing of cognitive process.

Question 3

Explain a bit about the subtraction method with brain activity.

Answer 3

Subtraction method: activity (C) – activity (A) = brain areas involved in S identification. Where is the highest brain activity/ difference.
A  simple Rt ‘’press the button as soon as stimulus appears’’ (S detection + motor execution)
C  Go/ no go ‘’ only respond if stimulus is a pear’’ (S detection + S identification motor execution)
You can do this for where and for when. But with when you look at the peak activity

Question 4

Depending on signal from which brain activity is inferred….. (which temporal resolution.)

Answer 4

depending on signal from which brain activity is inferred
- using neuroelectric signals directly caused by neural activity (high temporal resolution)
- using hemodynamic signals indirectly reflects neural activity inferred from the vascular response. (low temporal resolution)

Question 5

Which methods use neuroelectric signals?

Answer 5

• Using neuroelectric signals
• Electroencephalography (EEG)
• Magnetoencephalography (MEG)
• Electrocorticography (ECoG)
• Intracortical recordings (SEEG/ME)

Question 6

Which methods use hemodynamic signals?

Answer 6

6- Using hemodynamic signals
- Intracranial optical imaging
- Functional near-infrared spectroscopy (NIRS)
- Functional magnetic resonance imaging (fMRI)
- Positron emission tomography (PET)

Question 7

What is spatial resolution and temporal resolution?

Answer 7

It is about the amount of details you can see. Spatial resolution  the level of details on the location (of a process) temporal resolution  level of details on the dynamics (of a process)

Question 8

Which methods are invasive and which methods are non-invasive?

Answer 8

Non- invasive
- NIRS
- FMRI
- EEG
- MEG
Invasive
- PET
- ECoG
- SEEG
- ME

Question 9

There are two different ways to use neuroelectric signals. Please explain one.

Answer 9

pick up the electrical fields in the brain that are generated by neurons if they fire. `(membrane potentials, action potentials large enough create magnetic field) Electrodes measure
fluctuations resulting from electric current flows in (groups of) brain cells.
brain cells

Question 10

Explain a bit about EEG (electroencephalography).

Answer 10

Place electrodes put them on the skull by putting on the cap. Quite similar when you want to monitor the heart. Looking at electrical pulses in the brain.
* non-invasive recording of electrical brain activity via electrodes placed on the scalp
* compare voltage to a reference electrode that is not placed on the scalp

Question 11

What is the difference between EEG and MEG?

Answer 11

Electric field  electroencephalography (EEG) and Magnetic (uses electrons)  magnetoencephalography (MEG) (meg uses magnetometers)

Question 12

Explain a bit about MEG (magnetoencephalography).

Answer 12

non-invasive technique that records the weak magnetic fields produced by electrical currents by using very sensitive magnetometer