Class 5 - Research methods

Question 1

What is subtraction?

Answer 1

Damaged to a localized centre degrades a specific function. Only establishes necessary, not sufficient.

Question 2

What is disconnection and what are its assumptions?

Answer 2

Damage to a part of a network will impair the function. Assumes independent functions and unidirectional information flow. Assumes modularity.

Question 3

What is the multiple deficit brain model? What is a problem of it?

Answer 3

Acknowledges multiple lesions - especially both subtraction and disconnection. Ad hoc addition of boxes and arrows

Question 4

Explain alexia without agraphia using a multiple deficit model

Answer 4

Lesions in posterior corpus callosum and left primary visual cortex. Sight from right primary visual cortex cannot go to left angular gyrus for reading

Question 5

What is imbalance?

Answer 5

Lesions can lead to negative and positive symptoms that are imbalanced (ADHD)

Question 6

What are two results of atypical plasticity?

Answer 6

Phantom sensations and synthesia

Question 7

What is the difference between necessity and sufficiency?

Answer 7

Necessity = if taken away, the function will not work (air is necessary for human life)
Sufficiency = everything that causes the function (water, air, food is sufficient for human life)

Question 8

What are the problems with studies of brain lesions?

Answer 8

Neuropsychological tests are not “pure” indicators of function
Tends to assume static brain/behavior relationships
Lesions in one place may affect distant areas

Question 9

What is an additional issue of studies of atypical behavior?

Answer 9

The results are very specific to that particular individual. Is it generalizable?

Question 10

Pros and cons of examining postmortem brain tissue?

Answer 10

Pros: very detailed analysis of brain tissue
Cons: need to wait for person to die, selection bias

Question 11

What is the main advantage and disadvantage to brain imaging?

Answer 11

Advantage: allows in vivo studying of brain activity
Disadvantage: indirect measure of brain function

Question 12

What are the differences between event related and block design?

Answer 12

Block design = timed alternations between stimuli

Event related = random presentation of stimuli

Question 13

What two things are EEGs best at doing?

Answer 13

Sleep studies and epilepsy seizure localization

Question 14

What are the problems with animal models?

Answer 14

1. Animal brains are different from human brains
2. Developmental timing is different
3. Species typical behavior is different