Main Research Methods

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• A lot of research in cognitive psychology (CP) happens in labs
• Scientific and reliable - has great control over variables 

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• This type of research doesn’t tell us much about the world - it has LOW ECOLOGICAL VALIDITY

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• Take place in a natural situation - MORE ECOLOGICAL VALIDITY 

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• Less control over variables

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• Involve making observations of a naturally occurring situation
• They have HIGH ECOLOGICAL VALIDITY - but they are not massively reliable, as uncontrolled variables can affect the results.

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• Experimenter has little control over the variables & P’s can’t be randomly assigned to conditions.

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• Can now be carried out during a cognitive task. e.g. MRI scans have been used to show the blood flow in different brain areas for different types of memory tasks.

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• Provide support for the cognitive approach
• Use patients’ behaviour to test a theory

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• Hard to make generalisations 
• Individual differences between people mean that one subject may respond in a way that is totally different from someone else.

Case study of HM - Milner et al (1957)

Diagnosis:

• HM was a patient with severe and frequently epilepsy.
• His seizures were based in the hippocampus 
• In 1953, doctors decided to surgically remove part of that brain round this area.

Results:

• Operation reduced his epilepsy, but lead him to memory loss
• He could still form STM's, but was unable to form new LTM’s. E.g. he could read something over and over without realising that he had read it before. 
• Could still talk and show previous skills (procedural memory) 
• From tests, they found HM’s episodic memory (past events) and semantic memory (knowledge e.g. word meanings) was affected more that his procedural memory

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• The results of non-human studies can be applied to human cognitive abilities. E.g. discovering whether chimpanzees can learn language helps psychologists develop theories about how humans learn language

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• There can be many differences between humans and animals that results can be explained wrongly. E.g. you might conclude that chimpanzees can’t learn a spoken language because they lack the cognitive abilities. But its actually more likely to be because they lack physiological attributes, like a voice box. 

KEY STUDY: Study of language within chimps - Gardener & Gardener (1969)

Method: Washoe (a chimpanzee), was raised like a human child and taught American Sign Language (ASL)

Results: By the end of the 22nd month of the project, Washoe had learnt at least 34 signs Conclusion:

• The development in language in the chimp appeared to follow the same patterns as language developed in children (both speaking and ASL)
• Washoe learnt language at similar rates to children of the same age. 
• She didn’t learn Grammar

Evaluation:

• Ethical considerations - Washoe was taken from the wild and deprived of other chimps for companionship 
• External Validity - its not possible to accurately generalise results from the study of a chimp to the study of human children.