| What is brain plasticity? | - Our brain changes based on the demands we put upon it
- The brain can change functionally (Neural pathways strengthening/weakening) and structurally (Grey matter changing size and shape) |
| What is visual cortex? | - Part of the cerebral cortex, receives and processes visual info. |
| What are neurons | - Nerve cells which carry messages |
| What is grey matter? | - Pinkish part of the brain, main volume of the brain |
| What is the critical period? | - Start of a human or animals life in which their brain is most vulnerable to plasticity |
| What is behavioural blindness? | - Changes in behaviour of the kittens indicating they were blind to certain aspects of their environment |
| What is physical blindness? | - The physical and biological changes that occur when the neurons are no longer functioning properly |
| Visual tracking meaning | - The ability to follow the path of a moving object
- This is normally a smooth and accurate process using the eyes or head
- Cats use this when they are chasing a toy |
| Depth perception meaning | - The ability to judge the position of an object to establish how far away it is
- This ability is very useful and helps us daily e.g. walking down stairs |
| Monocular vision meaning | - Means ‘one eye’ and is when certain cells respond to information from only one of the two eyes |
| Binocular vision | - Refers to both eyes and an action that uses both eyes, such as reading a book |
| What is the Hippocampus (anterior and posterior)? | - In limbic system, controls navigation
- Anterior, at front, controls newly visited locations + navigation
- Posterior,at back, in charge of frequently visited locations + navigation |
| Aim | - Biological + behavioural effects of restricted visual experiences
- Dev. of visual cortex to find out if some of its properties are innate (as suggested by Hubel and Wiesel) or learned |
| What is the research method in Blakemore's and Cooper's study? | - Laboratory experiment |
| What was the experimental design in Blakemore's and Cooper's study? | - Independent measures design |
| What was the IV in Blakemore's and Cooper's study? | - Horizontal or Vertical stripes |
| What was the DV in Blakemore's and Cooper's study? | - Measuring visual and physical blindness |
| Background | - Hubel + Weisel found that neurons in the visual cortex (in cats) respond to light and visual info.
- So the brain of the cat is able to make sense of their surroundings |
| What is the sample in Blakemore's and Cooper's study? | - 2 Kittens (studied from birth until the completion of the research)
- In the critical period of their lives, from 0-3 months |
| What is the procedure in Blakemore's and Cooper's study? | - Kept in dark room from birth
- At 2 weeks, placed in cylinder for 5 hours per day
- After 5 months, critical period was over, experiments stopped
- Taken to well lit room, physical + behavioural blindness was measured
- At 7.5 months the kittens were put to sleep and had their neurological activity examined using an electrode |
| What are the results in Blakemore's and Cooper's study?
Visual findings (what the experimenters could see from the kittens) | - ‘Behavioural blindness’ shown
- Horizontally raised kittens did not see vertical lines/objects VV |
| What are the results in Blakemore's and Cooper's study?
Physiological findings (the neurological changes) | - Physical blindness occurred
- Certain cells were not firing
- Vertical kittens had problems with their horizontal plane recognition cells firing + vice versa
- Horizontal kittens had no neurons in the vertical orientation + vice versa |
| +In a normal cat how is the pattern of visual neurons? | - In a normal cat the pattern of visual neurons would be balanced, so they would have a balance of horizontal and vertical neurons. |
| Materials | - Kittens, vertical + horizontal condition, cylinders, lid |
| Controls | - Size + shape of the visual apparatus, black collar, the time spent, the age |
| What are the conclusions in Blakemore's and Cooper's study? | - Early visual experiences of kittens can change their brains
- Their visual cortex may adjust itself during maturation to the nature of its visual experience
- Brain dev determined by demands put upon it, than genetics
- Environment can determine perception at both a behavioural and physiological level – at least in cats |
| Strengths and weaknesses of the research method | - Strengths: High control, lab, generalizable to other kittens, can see cause and effect
- Weaknesses: One breed of kittens tested, only 2 tested |
| Data collected | - Quantitative, no. of neurons that responded in a particular orientation
- 75% of cells were binocular
- Qualitative, describing kittens reactions such as no startle response etc. |
| Strengths and weaknesses of the data collected | - Strengths: Both types of data collected. scientific quantitative. qualitative data were from observations
- Weaknesses: Not detailed quantitative data collected, not a lot of data for the length of time of the study |
| How is Blakemore's and Cooper's study ethical? | - The kittens were treated with the respect and responsibility laid out by the BPS for animal research |
| How is Blakemore's and Cooper's study unethical? | - Long lasting clumsiness - physical harm
- Emotionally distressing- psychological harm |
| Ecological validity | - Real kittens, generalisable, representative
- Lab lots of control collars on them limiting 130 degrees vision, real life kitten wouldn't have these restrictions
- Behaviour may be different in real life |
| How is Blakemore's and Cooper's study high in validity? | - High internal validity, controlled, confident that the findings were caused by the restricted visual environment
- Concurrent validity, measured both behavioural + physical behaviours of kittens
- Both measures concurred with one another as both behavioural and physical blindness was shown
- Both support the claim that the development of kittens brains has been influenced by the environment |
| How is Blakemore's and Cooper's study low in validity? | - Low population validity, 2 kittens is not applicable to how other kittens might respond
- Can't be applied to human brain plasticity |
| How is Blakemore's and Cooper's study high in reliability? | - Standardised, can be replicated, high internal reliability
- Quantitative data allows for consistency to be checked, so high external reliability to some extent |
| How is Blakemore's and Cooper's study low in reliability? | - Doesn't state explicitly the sample size, just the 2 conditions
- Ideal to see results of more kittens from each environment so we can be certain we didn’t get fluke results
- Low external reliability |
| What is a strength of the sample in Blakemore's and Cooper's study? | - However, the brains of cats have similar structures to human brain
- So some representation of brain plasticity in humans |
| What is a weakness of the sample in Blakemore's and Cooper's study? | - Results from just 2 cats, lack generalisability to other animals
- So hard to make claims about the envir. and how it impacts on brain development, especially in humans
- Low population validity/ generalisability to humans |
| How does Blakemore's and Cooper's study illustrate the interactionist debate? | - Shows both nature and nurture, therefore, is highly interactionist
- Useful as it expands our understanding of how innate factors interact with learnt behaviour to form what we do |
| How does Blakemore's and Cooper's study illustrate the nature debate? | - Nature provided the kitten with neurons with a preferred orientation
- They were also born with a fully formed visual cortex so this was innate |
| How does Blakemore's and Cooper's study illustrate the nurture debate? | - Restricted + manipulated envir. had a significant impact in terms of how the visual cortex developed
- e.g. the opposite neurons to the environment were not firing, so the kittens visual neurons adapted to their environment- learnt |
| How is Blakemore's and Cooper's study useful? | - Helps us understand functional brain plasticity + impact of enviro. on brain dev.
- Could lead us to develop practical applications on how best to train the brain to correct many behaviours |
| How does Blakemore's and Cooper's study lack usefulness? | - But what can we really learn from animals about the plasticity of the human brain? - limited sample - or even animal brains?
- Environment so unrealistic, cannot be applied to other particular environments of animals or humans |
| How is Blakemore's and Cooper's study scientific? | - Scientific equipment (electrode) measures neurophysiology, objective
- Controls, establish cause + effect between a specific change in environ. + whether that impacts upon behavioural + physical blindness
- Standardised, replicable |
| How is Blakemore's and Cooper's study unscientific? | - Qualitative data in lab
- When measuring behavioural blindness may have been misinterpreted so may have been subjective |
| Links to perspective and areas | - Biological area, investigating effect of the enviro. on brain dev. of cats
- Showed plasticity of the kittens brains as neurologically primed to prefer either horizontal or vertical orientation |
| How does Blakemore and Cooper link to the key theme | - Brain plasticity
- Brain dev. of cats brains of cats
- Visual neurons will change their preferred orientation to the visual experience presented |
