The use of technology in investigating cognitive processes (8/22)

Introduction

Conclusion

Tierney et al. (2001)

Maguire et al. (2000)

  • fMRI
  • MRI
  • PET
  • EEG

5 types of brain-imaging technology used to study active brain

  • CAT

CLA = mental processes can + should be studied scientifically

each scanner has its own strengths + limitations + appropriate to various situations

cognitive processes discusses: memory + language

B.I technology = MRI + PET

  • MRI scans used to to compare taxi drivers' hippocampi with already existing images of healthy 'normal' males

Results: taxi drivers' left + right hippocampi were larger in vol. than 'normal' ppl

Method: based on knowledge that taxi drivers do 2 year course to learn map of london

  • other parts of taxi drivers' hippocampi were smaller

Aim: compare ippocampi strutture in brain sof taxi drivers + 'normal' ppl

Conclusion: redistribution of grey matter

example of MRI scans investigating cog. process of memory

neurons were stronger in areas of brain used most

(spatial memory skills required to remember roads)

MRI enabled Maguire et al. to observe structures in brain

found connection between hippocampi (bio factor) + memory skills (cog. process)

  • result of encephalitis suffered aged 6 weeks

Method: MA = man pp with norm. speech functions in a norm. speech study

  • lesion discovered in left lobe of his brain

Aim:evaluate bilingual language compensation followed brain damage in childhood

  • used sign language from young age (parents= deaf)

produces image, red = most active, blue = least

  • the brain damage should have prevented him from speaking

PET = glucose-tracer injected > more gl. is absorbed where brain is most active

  • was lesion due to being able to speak despite brain damage?
  • compared MA to 12 control pp's fluent in sign language
  • PET scans used while pp's produced narrative speeches / signs

example of PET scans investigating cog. process of language

MRI = magnetic fields + radio waves produces 3D image of brain

Results: MA's right hemisphere was more active than control pp's

Conclusion: language developed in right hemisphere rather than left (adaptation that followed brain damage)

PET scan used to observe active brain areas (bio factor) while MA produced language (cog. process)

all contribute to investigating relationship between cog. processes + behaviour

diff. brain scans are used depending on individual, cause of problem + cog. process being studied

each type has own advantages / disadvantages depending on nature of the study

brain imaging technologies = v. useful for investigating cog. processes