Biological area: Blakemore and Cooper Flashcards
What is the name of the research which inspired Blakemore and Cooper to conduct their experiment?
Hirsch and Spinelli
What did Hirsch and Spinelli find?
That cats neurons developed according to which orientation that had been exposed to (either vertical or horizontal
Define neuroplasticity
The ability of the brain to change shape/structure (e.g. form new neural connections in response to changes in the environment
What was the first aim of Blakemore and Cooper’s study?
To compare the behavioural consequences of raising kittens seeing only horizontal or vertical stripes
What was the second aim of Blakemore and Cooper’s study?
To investigate the neurophysiological effect in kittens’ visual cortex
What was the research method used in Blakemore and Cooper’s study?
Lab experiment
Why can Blakemore and Cooper’s study be considered a lab experiment?
Because clear controls were used with two cats each experiencing a different environment
What was the experimental design used in Blakemore and Cooper’s study?
Independent groups
Describe the sample used
2 kittens from birth until they were one year old
What was the environment for the first two weeks of the cats’ lives?
They were housed in a completely dark room
From how old were the kittens exposed to the vertical/horizontal cylinder environment?
From 2 weeks old
How long did the kittens spend in the cylinder a day?
5 hours a day
Describe the cylinder (height and diameter)
46 cm diameter, 2 m high
What was the purpose of the glass platform within the cylinder?
For the kitten to stand on
What did the cat have to wear to restrict its vision so that it could only see the stripes?
A black collar
To what angle did the black collar restrict the kittens view to?
130 degrees
At what age did the daily exposure to the vertically/horizontally orientated environment end?
5 months old
What was the IV in this study?
Horizontal or vertical orientation
What type of deficit did the kittens had when first exposed to the well lit room?
Visual
What type of response did they not show despite having normal pupillary reflexes? (initial reactions)
Startle response
How did the kittens navigate around the room for the majority of the time? (initial reactions)
Via touch
When did kittens display a fear response? (initial reactions)
Only when they felt they had reached the end of a table or ledge
What would the kittens not do which showed a lack of visual placing? (initial reactions)
They would not put feet forward to meet the edge of a table/ledge
After how many hours did most of the deficits disappear?
10 hours
What things did the kitten begin to display after 10 hours?
Startle reflex, visual placing and would jump easily from chair to the floor
Describe the kittens visual tracking of moving objects after 10 hours exposure to the well lit room?
Clumsy/jerky
What would the kittens often reach for after 10 hours of exposure to the well lit room?
For moving objects beyond their grasp
What did the kittens often do when they explored the room?
Bump into things
What was presented to the kittens to test their startle reflex?
A perspex sheet with thick black and white stripes on it
What were the results from the startle reflex test with the perspex sheet?
When it was presented in the ‘right’ direction the cats would show a startle reflex and when it was presented in the ‘wrong’ direction the cats would show no reaction
Describe the other test used to test the differences in behaviour from the two cats?
A rod was shaken in front of the cat (a game in which normal cats would chase the rod) in both directions to see how each cat would interact with the rod
What were the results from the test involving the rod?
When the rod was presented vertically to the vertically orientated cat, the cat would respond to the rod and would ignore it when it was presented horizontally (vice versa with the horizontally orientated cat)
At what age were the cats anaesthetised with nitrous oxide?
7.5 months
What happened to the cats after they were anaesthetised?
They were paralysed with succinylcholine and their eyes were opened
After the cats’ eyes were opened what did the experimenters insert into the primary visual cortex?
Electrodes
What was the purpose of inserting electrodes into the primary visual cortex?
To take electrical readings from individual neurons
What was the purpose of the visual neuron activity?
To show optimal orientation for each neuron when shown bright slits or edges of light
How many neurons had recordings taken from in total?
125
How many neurons were recorded from the horizontally reared cat?
52
How many neurons were recorded from the vertically reared cat?
72
Describe how the neurons in a normal cat’s visual cortex would be
They would be balance ‘around the clock’
In what direction did the horizontally reared cat have no neurons?
In a vertical direction
In what direction did the vertically reared cat have no neurons?
In a horizontal direction
What did the differences between the cats suggest about neurons? (conclusion)
That they can change their preferred orientation according to the stimulation that they receive, matching the ability of the brain to respond to the features in its visual input
In what 2 ways can Blakemore and Cooper be defended in terms of ethics?
They only used 2 cats, a minimum
Their work was also approved by the home office
In what ways can Blakemore and Cooper be criticised in terms of ethics?
Although they state ‘the cats did not seem upset..’ we cannot know this for sure
Was the procedure standardised and replicable (internally reliable)?
Yes, well controlled, although ethical guidelines make replication unlikely
Was the sample large enough to suggest a consistent effect (externally reliable)?
No, but it is unlikely that the cats were abnormal
Was it an accurate test of brain plasticity (construct validity)?
Yes because each cat’s neurons responded in the way predicted
How could this study be said to have concurrent validity?
Both the behavioural and neurophysiological results matched
Did the experiment resemble a real life situation?
No, keeping the cats in a dark room
Can the sample be generalised from (population validity)?
Not to humans
Why is it not appropriate to discuss ethnocentrism in relation to this study?
Because the participants were cats
In what way can this study be argued to support the nurture debate?
The environment the cats were in changed the visual neurons of their cortex
In what way can this study be argued to support psychology as a science?
Clear controls/objective measures and could be proved wrong
