Core study 19- Blakemore & Cooper (B) Flashcards
Impact of early visual experience
Background
What does monocular mean?
Something appears in just one eye
Background
What does binocular mean?
Something appears in both eyes
Background
What did Hubel and Wiesel find about a cats’ neurons in the visual cortex?
Which side of the Nature v Nurture debate do they support?
- One type of neuron responds to orientation- whether objects are horizontal or vertical
Nature (innate)
Background
What did Hirsch and Spinelli find about the normal cortical (eye cell) in cats?
Which side of the Nature v Nurture deabte does this support?
- If one eye saw horizontal lines and the other saw vertical lines, it’s organisation would change
- Cells became exclusively horizontal/ vertical depending on what they’d seen
Nurture
Aim
What did B+C want to investigate in terms of the development of the primary visual cortex?
(To investigate the development of the primary visual cortex) and to find if it’s properties such as orientation selectivity are innate or learned
Method
What kind of experiment was this?
How do you know?
Lab experiment
Controls, biological area= controls and regions of brain
Method
What experimental design was used for the study?
Independent measures design- each cat did just one condition
Method
What was the IV?
Whether kittens were reared in a horizontal or vertical environment
Method
What was the DV?
Their visuomotor behaviour (sight and movement)- whether horizontally raised kittens could detect vertically alligned objects and vice versa
Sample
What was the sample of the study?
Sampling technique?
2 laboratory kittens raised in darkness until 2 weeks old- one in horizomntal environment, other in vertical environment
Opportunity sampling
Procedure
Where were the kittens placed after they reached 2 weeks old?
Placed in tall cylinder for about 5 hours a day with vertical or horizontal lines
Procedure
What did the kittens wear around their necks to restrict vision?
A wide black collar with a width of around 130 degrees
Procedure
Where were kittens placed after they got to 5 months old?
Placed in well lit, furnished room, and were observed on their visuomotor behaviour for several hours a week
Procedure
What happened to the kittens at 7.5 months old?
They were both anaesthetised so that their brain structures could be examined (neurophysiology)
Results
What happened to the kittens regardless of the environment they were in, in terms of visuomotor behaviours?
They were visually impaired and showed no startle repsonse when an object was thrust towards them
Results
How did the kittens display bavioural blindness?
- Kitten in horizontal condition couldn’t see vertical objects
- Kitten in vertical condition couldn’t see horizontal objects
Results
How long did it take for some (minimal) vision control to return to the kittens?
After around 10 hours
Results
What percentage of cells were binocular?
75% - in most ways, kittens’ visual cortex was like the average kittens’
Conclusions
What was concluded about visual experiences in the early life of kittens?
They can modify their brains (plasticity)
Conclusions
Is brain development determined by environment or genetics based on the results from this study?
Determined by environment rather than genetics
Conclusions
Can the research be applied to humans?
It is questionable
GREEDUM
How can generalisability be argued as a weakness?
2 young kittens kept in darkness for two weeks- does not reflect intended target population
GREEDUM
How can reliability be argued as a strength?
Used standardised procedure, kept kittens in environments for equal amounts of time at same age
GREEDUM
How can ethics be argued as a weakness?
Both cats euthanised at 7.5 months, kept in darkness- not protected from harm
GREEDUM
How can data be argued as a strength?
Kittens found visually impaired, no visual placing or startle response- qualitative data
