biopsych- ways of studying the brain

Question 1

what does fMRI do

Answer 1

fMRI is a brain scanning technique that measures the blood flow in the brain, when a person performs a task.
Neurons that are the most active use the most energy
The energy requires glucose and oxygen
oxygenated hemoglobin has distinct magnetic properties than deoxygenated hemoglobin
this creates a dynamic 3d map of the brain where the blue colour is low activity and the red is high activity

Question 2

does fMRI have good spatial resolution

Answer 2

yes it has a spatial resolution of 1 mm, which precisely identifies the active regions of the brain and patterns overtime when ppt completes a task

Question 3

does fMRi have good temporal resolution

Answer 3

No fMRI has a delay of 1-4 seconds after neurons activate and the blood arrives at the neurons
fast brain processes such as vision can’t be studied

Question 4

limitation of fMRI

Answer 4

the scanning machines are big and expensive and ppt needs to be still, which means fMRI can’t study body movement

Question 5

define the EEG

Answer 5

-EEG scanners measures electrical activity through electrodes attach to the scalp
-information is processed as electrical activity in the form of action —-potential or nerve impulses
-the electrical charges are then graphed over a period of time
- there are four EEG patterns: alpha, beta, theta, delta
amplitude is the intensity/ size of the activity
frequency is the speed and quantity of activity

Question 6

strengths for EEG

Answer 6

-EEG is a non invasive way that helps epilepsy as well as
-experimentally to learn more about sleep (alpha waves- light sleep/ delta waves- deep sleep)
-it allows people to move and is cheaper than fMRI

Question 7

does EEG and ERP scanners have good spatial resolution

Answer 7

no it have can detect superficial (surface) & general areas of the brain

Question 8

does EEG and ERP scanners have good temporal resolution

Answer 8

yes it shows the activity every millisecond, showing the activity in nearly in real time

Question 9

define ERP

Answer 9

event related potentials
electrodes attached to the scalp same as EEG but researcher presents a stimulus many times and looks for the activity related to it (event related), then the average response is graphed

Question 10

what is latency in terms of the ERP

Answer 10

Latency is the TIME INTERVAL between the presentation of the stimulus and the response

Question 11

strength of ERP

Answer 11

ERP allow the researcher to isolate cognitive processes in the brain whereas EEG only looks at general areas

Question 12

define post mortem

Answer 12

in brain dissection the brain is treated with a chemical to make it have a firmer texture, in order to precisely cut into it. This occurs in unusal brains that suffered with trauma or when a person had abnormal behaviours

Question 13

name the 2 examples of post mortem examinations

Answer 13

Broca and Wernicke are both researchers who found lesions in patients brain e.g. patient tan

Question 14

strength of post mortem

Answer 14

allows a detailed examination of neurochemical aspects that other techniques can’t do, but it is invasive
- spatial resolution, can study microscopic structures e.g. neuronal levels