Lab 1

Question 1

Why is sampling rate important?

Answer 1

• high rate = represents actual event, smooth line
• low rate is not representative

Question 2

What does compressing our data allow us to do?

Answer 2

allows us see patterns
- e.g. HR change with breathing pattern

Question 3

What difference between eyes closed and open could be measured with EEG?

Answer 3

alpha waves

Question 4

What is an alpha wave? What range of wavelengths?

Answer 4

an electrical waveform visible on EEG between 8-12 Hz when an individual has their eyes closed

Question 5

Why isn’t the alpha waveform present when eyes open?

Answer 5

eyes open = more noise/signals coming in to occipital lobe= depolarisation and repolarisation cancel out alpha waves

Question 6

Define P100.

Answer 6

time it take for light hitting retina to get to visual cortex

Question 7

Define latency.

Answer 7

latency = time between stimuli and response

Question 8

Why can’t EEG be solely used to determine brain death?

Answer 8

EEG = summed electrical field potential of large numbers of neurons, superficial as electrodes on skin
- deep brain activity for homeostasis isn’t picked up on EEG
- EEG may also appear silent because of temporary influences of drugs etc but doesn’t mean that brain activity won’t resume