Lesson 9 - Studying the Brain

Question 1

Ways to Study the Brain

Answer 1

Post Mortem Examinations
Functional Magnetic Resonance Imaging (fMRI) Scans
Electroencephalogram (EEG)
Event Related Potentials (ERPs)

Question 2

Post Mortem Examinations

Answer 2

Studying the brain once the person has died
Studies have found link between brain abnormalities and psychiatric disorders
E.g. evidence of reduced glial cells in frontal lobe of patients with depression

Question 3

Post Mortem Examinations Evaluation Points

Answer 3

Detail
Validity
Generalisation

Question 4

Post Mortem Examinations Evaluation
Detail
Positive

Answer 4

Allow for more detailed examination of anatomical and neurochemical aspects of brain which would not be possible with other methods of studying the brain
Enabled researchers to examine deeper regions, such as hippocampus and hypothalamus

Question 5

Post Mortem Examinations Evaluation
Validity
Negative

Answer 5

People die in a variety of circumstances and at varying stages of diseases
Similarly, length of time between death and post-mortem, and drug treatments, can all affect brain
Therefore lack validity

Question 6

Post Mortem Examinations Evaluation
Generalisation
Negative

Answer 6

Studies have small sample
Sample cannot be representative of target population
Findings cannot be extrapolated and generalised to wider population

Question 7

Functional Magnetic Resonance Imaging Scans

Answer 7

Provide indirect measures of neural activity
Uses magnetic fields and radio waves to monitor blood flow in brain
Measures change in energy released by haemoglobin, reflecting activity of brain to give a moving picture of the brain
Activity in regions of interest can be compared during a base line task and during a specific activity

Question 8

fMRI Scans Evaluation Points

Answer 8

Brain Activity
Spatial Resolution
Complexity
Validity

Question 9

fMRI Scans Evaluation
Brain Activity
Positive

Answer 9

Captures brain activity as opposed to post mortem examinations which purely show physiology of brain

Question 10

fMRI Scans Evaluation
Spatial Resolution
Positive

Answer 10

Good spatial resolution

Refers to the smallest feature that a measurement can detect

Question 11

fMRI Scans Evaluation
Complexity
Negative

Answer 11

Interpretations are complex and are affected by poor temporal resolution (resolution of a measurement with respect to time), biased interpretations and by the base line task used

Question 12

fMRI Scans Evaluation
Validity
Negative

Answer 12

fMRI research is expensive leading to reduced sample sizes

Negatively effects validity of research

Question 13

Electroencephalogram (EEGs)

Answer 13

Directly measure general neural activity in brain, usually linked to states like sleep and arousal
Electrodes placed on scalp and detect neural activity below where they are placed
Differing numbers of electrodes used dependent on focus of research
When electrical signals from different electrodes are graphed, the resulting representation is called an EEG pattern
Patients with epilepsy show spokes of electrical activity
Patterns of those with brain injury show slowing electrical activity

Question 14

Electroencephalogram Evaluation Points

Answer 14

Clinical Diagnosis
Cheaper
Spatial Resolution

Question 15

Electroencephalogram Evaluation
Clinical Diagnosis
Positive

Answer 15

Useful in clinical diagnosis

E.g. can record neural activity associated with epilepsy so doctors can confirm person is experiencing a seizure

Question 16

Electroencephalogram Evaluation
Cheap
Positive

Answer 16

Cheaper than an fMRI

Therefore can be more widely used in research

Question 17

Electroencephalogram Evaluation
Spatial Resolution
Negative

Answer 17

EEGs have poor spatial resolution

Question 18

Event Related Potentials (ERPs)

Answer 18

Electrodes placed on scalp and directly measure neural activity in response to a specific stimulus introduced by researched
ERPs are difficult to pick out from other electrical activity being generated within the brain
To establish specific response to a target stimulus, requires many presentations of this stimulus and the responses are then averaged
Any extraneous neural activity that is not related will not occur consistently, whereas activity linked to stimulus will

Question 19

Event Related Potentials Evaluation Points

Answer 19

Measure
Cheap
Temporal Resolution
Spatial Resolution
Neocortex

Question 20

Event Related Potentials Evaluation
Measure
Positive

Answer 20

ERPs can measure the processing of a stimulus even in the absence of a behavioural response
Therefore it is possible to measure covertly the processing of a stimulus

Question 21

Event Related Potentials Evaluation
Cheap
Positive

Answer 21

ERPs are cheaper than an fMRI

Therefore more widely used in research

Question 22

Event Related Potentials Evaluation
Temporal Resolution
Positive

Answer 22

ERPs have good temporal resolution unlike fMRIs

Question 23

Event Related Potentials Evaluation
Spatial Resolution
Negative

Answer 23

ERPs have poor spatial resolution unlike fMRIs

Question 24

Event Related Potentials Evaluation
Neocortex
Negative

Answer 24

Only sufficiently strong voltage changes generated across the scalp are recordable
Important electrical activity occurring deeper in the brain is not recorded
The generation of ERPs tend to be restricted to the neocortex