Blakemore and Cooper Flashcards
What was the key theme?
brain plasticity
define brain plasticity
brain adapts and changes according to what you do in your life
who were they inspired by
Hits h and Spinelli
Describe Hirsch and Spinellis study
-Interested in neurons in the visual cortex of the brain
-Found they could change the way the neurons in the visual cortex aligned themselves by controlling what kittens could see as they grew up
-Kittens were raised could only see vertical stripes in one eye and horizontal stripes in the other eye.
-Where then released into an everyday environment, the researchers found that they had visual impairments
describe visual cortex
the part of the brain that receives and processes sensory nerve impulses from the eyes
describe startle responses
The ‘backing off’ reaction of a cat when an object is moved quickly towards their face
describe visual placing
When a cat puts its feet out to meet the edge of a surface
What was the main aim
To investigate how being raised in a visually restrictive environment would affect the visual brain development of cats
What were the 2 smaller aims
-Compare the behavioural consequences of raising kittens seeing only horizontal or vertical stripes.
-Investigate the neurophysiological effect on neurons in kittens’ visual cortex (brain plasticity)
sample
2 kittens from birth until approximately 1 year of age.
What was the environment for the first 2 weeks of the kittens lives?
complete darkness 24 hours a day
What was the environment from two weeks until 5 months?
Put in striped cylinder for 5 hours a day
Wore black collar to hide body
One had vertical and other had horizontal stripes
What happened to the kittens at 5 months old?
Taken to well lit room with furniture
What was the IV
orientation of the stripes within the cylinder (either horizontal or vertical)
What was the experimental design
independent measures
What visual deficits did the kittens show at first? (behavioural findings)
-navigated by touch
-clumsy
-normal pupillary reflexes
-no startle response
-no visual placing
What deficits did they recover from after 10 hours of the well lit room?
visual placing
startle response
What deficits remained after 10 hours in the well lit room?
clumsy in following moving objects
bumped into objcets
How did the horizontal and vertically raised cats differ?
We’re virtually blind to the opposite orientation to their upbringing
Shook rod in front of cat
What was the procedure for the neurophysiological test
the cats (7.5 months) were anaesthetised and paralysed.
eyes were opened and took electrical readings from individual neurons. activity was recorded.
Describe the neurophysiological findings
Visual neurons within the visual cortex had aligned themselves to match the environment the kitten was brought up in. There were little to no neurons aligned to the opposite direction
-had no need for neurons in the other direction and therefore these were moved elsewhere.
What type of data was collected for behavioural findings
qualitative descriptions
What type of data was collected for neurophysiological findings
quantitative (based on alignment of neurons)
conclusions
difference suggests neurons can change their preferred orientation according to the stimulation they receive, matching the ability of the brain to respond to the features in its visual input.
How can ethics be defended
Was no alternative replacement to animals within this research
They reduced the impact to the minimum amount of cats (2)
They refined the procedure by only having the cat in the cylinder for 5 hours a day
How can the study be criticised in relation to ethics
There is not many practical applications of the research and therefore perhaps was not worth harming the kittens for
discuss ethnocentrism
There is not many practical applications of the research and therefore perhaps was not worth harming the kittens for
internal reliability
The procedure was highly standardised and replicable due to the high level of controls
external reliability
Only 2 kittens were used in this study but perhaps this doesn’t matter as we are investigating biological concepts
internal validity
good test of brain plasticity as the only difference in the procedure for the kittens was the direction of the stripes.
population validity
possible problem with generalising beyond the species of kittens
concurrent validity
cats showed some deficits in 2 separate tests to check perception of other orientation
ecological validity
Not a realistic scenario as the environment was so visually restricted. This doesn’t happen in real life.
How does the study link to nature/nurture debate
Nurture as brains can change in response to the visual environment
how does study link to psychology as a science debate
study is replicable, objective and falsifiable
how does the study relate to individual/situational debate
behaviour dependant on situation of cylinder orientation
how does study relate to usefulness debate
study isn’t useful
