Biopsychology(ways of studying the brain)

Question 1

Post-mortem examinations -

Answer 1

• Used to understand underlying neurobiology of a particular behaviour
• May study a person who is alive that suggests underlying brain damage
  -When the person dies the researchers can examine the brain and check for abnormalities that may explain the behaviour of which are not found in control individuals.
  -Example is Broca’s research into patient Tan, who displayed speech problems when alive and was found to have problems in speech production in Broca’s area.
• May also be used to undercover structures involved in memory.

Question 2

Functional magnetic resonance - (scanning technique) (fMRI)

Answer 2

• Technique used for measuring the changes in brain activity while they perform a task.
• Measures changes in blood flow to specific regions in the brain.
• If a particular area receives more oxygen that area has become more active.
• Therefore, researchers are allowed to produce maps which show specific that are involved in different neural activity
• For example an individual may do alternate tasks which show them looking at a stimulus then not looking. The resulting fMRI data can be used to identify the brain areas where there is a matched pattern of change.

Question 3

Electroencephalogram - (scanning technique)

Answer 3

• Measures electrical activity in the brain.
• The electrodes are measured by a scalp which is placed on the head
• Electrical signals are graphed over time a period of time to form electrodes
  -Can be used to assess brain disorders like epilepsy, E.G EEG readings of patients with epilepsy show spiked readings of EEG
• 4 basic EEG patterns of alpha, beta, delta and theta waves

Question 4

Event related potentials - (scanning techniques)

Answer 4

• Very small voltage channels in the brain that are triggered by specific events or stimuli.
• ERPs are difficult to pick out from other electrical activities which are being generated within the brain at a given time.
• Any extraneous neural activity not directly related to the stimulus will not occur consistently, whereas activity related to the study will.
• Can be divided into two categories. Waves occurring within the first 100 milliseconds after presentation of stimulus. ERPs generated after the 100 milliseconds reflect the manner in which subject evaluates the stimulus for cognitive. ERPs demonstrate information processing.

Question 5

fMRI - strength

Answer 5

fMRI is non-invasive (no instruments into the body), therefore doesn’t expose the brain to harmful radiation, as is the case with other scanning techniques.

Question 6

fMRI - limitation

Answer 6

As it changes measures in blood flow in the brain it doesn’t measure neural activity, also meaning it is not a truly quantitative measure of mental activity in the brain.

Question 7

EEG - strength

Answer 7

Provides recordings of the brain in real time rather than it just being a still image in the passive brain. Meaning researchers can accurately measure a particular task with the brain associated with it actively.

Question 8

EEG - limitation

Answer 8

EEG can only be detected in superficial regions of the brain, it doesn’t reveal what is happening in deeper regions of the brain for example the hippocampus. Electrodes can be achieved in these areas in non-human to achieve this but is not ethically permissible for it to be done in humans as it is too invasive.

Question 9

ERP - Strength

Answer 9

ERP can measure a response of a stimuli even in the absence of a behavioural response, ERP make it possible to monitor the processing of a particular stimulus without a person actually needing to respond to it.

Question 10

ERP - limitation

Answer 10

As ERPs are so small it makes it hard to pick them out from other electrical activity in the brain. It requires a larger number of trials to collect meaningful data, places limitations of what the readings can actually answer.

Question 11

Post-mortem examination - strength

Answer 11

Allow for a more detailed examination of anatomical and neurochemistry aspects of the brain, which would be hard to solve with non-invasive scans like fMRI. It allows researchers to reach deeper regions of the brain like the hippocampus and hypothalamus.

Question 12

Post-mortem examinations - limitations

Answer 12

As people die in a variety of circumstances and at varying stages of diseases, these factors can affect post-mortem examination of the brain. Similarly the length of time between death and post-mortem and drug treatments are classed as confounding influences when measuring the different cases.