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1

why do neurons differ in length and size?

connect to different brain regions > further apart require longer neurons

2

receive messages from other cells =

dendrites

3

electrical activity can be detected on the scalp using an _____

EEG

4

what is the function of fMRI?

how the brain is responding and where activity is generated in specific brain regions

5

why do we need to have an anatomical scan for each ppt?

everyone has a different brain structure

6

Oxygen is delivered to neurons in ________ in _______ RBCs

haemoglobin, capillary

7

why do neurons need oxygen?

because they lose energy when they fire electrical signals > this needs to be replenished

8

why would a resting neuron show reduced blood flow?

doesn't need as much O2 as not firing

9

what does fMRI record?

blood flow towards activated areas of the brain

10

Hb is ________ when oxygenated and _______ when deoxygenated

diamagnetic, paramagnetic

11

does diamagnetic Hb or paramagnetic Hb have a stronger magnetic field?

diamagnetic > as is oxygenated!

12

what is the fMRI response to oxygen called?

the BOLD response

13

what does BOLD stand for?

Blood Oxygen Level Response

14

there is an initial ____ in haemodynamic blood flow followed by an _____ that overcompensates for the amount of oxygen used

dip, increase

15

when does the increase in oxygen to Hb start happening?

approx 4 seconds (quite slow)

16

what is the con associated with fMRI?

the delay between when we respond to a stimulus and when we can measure a response (low temporal resolution)

17

why is there a delay in measuring a response?

because we have to wait for the blood supply to be redirected to that area

18

what shows how magnetic the Hb is?

the MR signal

19

when does the MR signal peak in the BOLD response?

between 4 and 8s

20

too much O2 in the area once it is oxygenated (peak) then dissipates out and brings it back to normal levels =

primary response

21

what happens after the primary response?

a negative overshoot where area becomes slightly deoxygenated

22

what are the 3 planes that the brain can be viewed?

coronal (front), saggiato (side) and axial (down)

23

why might we combine EEG and fMRI?

they have complementary pros and cons which allows us to deepen our knowledge

24

which method has low temporal resolution but high spatial resolution?

fMRI

25

which method has low spatial resolution but high temporal resolution?

EEG

26

give an example of where EEG and fMRI are combined

early visual processing

27

how we process visual stimuli and the immediate response =

early visual processing

28

what stimulus do we often use for EEG studies testing visual processing?

changing checkerboard

29

a robust response to a stimulus that shows a consistent change that happens repeatedly and shows a pattern =

ERP

30

how is 1 ERP trace in response to a stimulus produced?

average the traces across multiple trials