ways of investigating the brain

Question 1

define post mortem

Answer 1

• examination of the brain after death
• the damage seen on the brain can be associated with brain impairments from when they were alive

Question 2

advantages of post mortem

Answer 2

• does not cause stress as a procedure after death
• has provided findings for Broca and Wernicke to identify language centers of the brain

Question 3

disadvantages of post mortem

Answer 3

• cause and effect?
  legions in the brain might not necessarily have caused the change in the brain function observed during the patient life

Question 4

how are fMRI’s carried out?

Answer 4

• measures increased blood flow to brain sites when individuals are asked to perform cognitive/physical tasks
• increased blood flow = increased demand for oxygen in that area
• generated 3D images that can be used to locate the mental activites in the brain

Question 5

advantages of FMRI’s

Answer 5

• moving picture of brain activity = processes unfold in the
  brain
• non-invasive = does not expose the brain to potentially harmful radiation like PET scans do.
• Creates a very clear/high-resolution image of the brain

Question 6

disadvantages of FMRI’s

Answer 6

• Very expensive
• The person must stay very still
• may overlook the interconnectivity of brain sites= it fails to account for the importance of brain sites
  connecting/communicating with each other
• Consciousness and personality haven’t been found to be localized to any one part of the brain

Question 7

what are Electroencephalograms (EEGs)

Answer 7

• measures the electrical activity of neurons in the brain
• done using electrodes attached to the scalp, and measures how electrical activity in the brain varies over time/in different states (e.g. waking vs. asleep).

Question 8

advantages of EEGs

Answer 8

• Records brain activity over time = monitor changes as a person switches from task to task or one state to another (e.g. falling asleep)
• EEGs have medical applications in diagnosing disorders such as epilepsy and Alzheimer’s

Question 9

disadvantages of EEGs

Answer 9

• EEGs only monitor electrical activity in the outer layers of the brain = cannot reveal
  electrical activity in deeper brain sites

★ Not highly accurate – therefore cannot distinguish differences in activity between 2 closely adjacent areas.

Question 10

what are event related potential ERPs

Answer 10

• ERP’s is the measured brain response that is the direct result of a specific sensory, cognitive, motor event
• recorded using an EEG

Question 11

advantages of ERPs

Answer 11

• provide a continuous measure of neural activity in response to a stimulus = changes to the stimulus can be directly recorded: e.g. if a blue-colored slide turned green.
• only takes milliseconds to take a reading, compared to several seconds for the fMRI.

Question 12

disadvantages of ERP’s

Answer 12

• only monitoring electrical activity in the outer layers of the brain = cannot reveal electrical activity in deeper brain sites.