Supplementary Info for Bode

Question 1

What is the TR in MRI and how long is a TR

Answer 1

TR = time to repeat = time to take to measure/scan the brain once, which depends on the thickness of the slice

usually 1-3 secs

Question 2

What is an alpha rhythm

Answer 2

8-13 Hz of signals that are generated by humans when we close our eyes

Question 3

What is the intra-cranial EEG and why isn’t it used by researchers today

Answer 3

expensive
hard to use
possible breach of ethical considerations

Question 4

How much do the EEG signals have to be amplified to be measured and how strong are the raw signals

Answer 4

1,000 - 100,000
10-100

Question 5

What is the sample frequency range of EEG

Answer 5

256-1024 Hz

Question 6

What are the components that are removed by ICA

Answer 6

EOG
EMG
ECG

Question 7

What is ERP and where and when

Answer 7

A negative potential shift of up to 10 mV in the central electrodes after 80-100 ms of the erroneous response

Question 8

Explain T1 and T2 weighted images

Answer 8

T1 images
components with the faster relaxation rate = stronger signals = white
therefore
white matter (fat) > grey matter > CSF

T2 images
components with the faster decay rate = weaker signal = grey
therefore
white matter (fat) < grey matter < CSF

Question 9

Phase encoding gradient affects the __ axis and the frequency encoding gradient affects the __ axis

Answer 9

y axis, x axis

Question 10

what is the minimum size unit that is required for the signals of the EEG to be measured

Answer 10

At least 10,000 neurones aligned to the scalp