case studies

• features of case studies-

  • a lot of information is collected about the case and this is likely to involve a variety of techniques such as interviews or observations
  • usually focused on one person
  • indeph data
• Case study of HM

  • a key piece of research that established that memory is linked to the hippocampus and composed of different functions
  • he suffered from epilepsy caused by a head injury when he was seven years old
  • as he grew up his seizures got worse and surgery was his only hope
• what made HM experience significant?

  Brain surgeon William Scoville proposed to remove Henry's temporal lobe ( performing bilateral medial temporal lobe resection) which included parts of the hippocampus and amygdala.

  When Henry recovered from surgery he suffered severe amnesia- he could remember his childhood however he struggled to remember the years leading up to surgery having major gaps in his memory BUT more importantly had severe anterograde amnesia meaning he could not form new memories
• The HM aim and procedure- Milner

  • aimed to investigate the extent and nature of HM's memory deficits and how they relate to his brain damage whilst also the function of brain structures like hippocampus
  • Milners early test involved recall tasks testing HMs childhood, also tested his cognitive faculties like general knowledge and IQ. Milner used maze tasks when testing Henry by testing him over and over to see if he would remember the route.
  • Milner also used a star where Hm could only see the reflection of the star and his hand in a memory being asked to re attempt the task several times
• Hm results and conclusions- Milner

  • Hm forgot all new experiences after 30 seconds
  • Henry loved to describe clear memories of his childhood over and over though he lacked a context for them and the face he saw in the mirror surprised him
  • over 252 attempt's Hm never showed any improvement in the maze task
  • However he did show.improvement in the star tracing task making fewer mistakes on attempts by Day 3 he was making fewer than 5 mistakes each time
  • Milners data shows a clear difference between ST and LT memory suggesting that the hippocampus plays a vital role short term memories into LT
• Case study of HM- reliability

  All of memory tests and puzzles show consistent results with HM as many researchers replicated these on HM however the case sudy itself os hard to replicate now that HM is dead there may never be a patient like him
• Case study of HM-Application

  Has been HUGE- before HM psycholigsts thought that memory was a single function and took place all across the brain and is now clear that there are different functions in different parts

  • led to development of multi store memory as the understanding of there being STM and LTM
• Case study of HM- ethics

  As he had no memory he was not in a position to provide informed consent for any of the tests carried out on him and he never consented to his brain being preserved nor were any of his closest relatives approached
• strengths of case studies:

  • rich meaningful data
  • high ecological validity
  • lead to new insights within psychology
• weaknesses of case studies:

  • cannot replicate- not reliable
  • difficult to generalise as the data us ideographic
  • researcher bias which reduces scientifically credibility
• Case study of KF- Shallice and Warrington 1974

  KF was a 28 year old man who had experienced a motorcycle accident at the age of 17. He had a parieto-occipital fracture and was unconscious for 10 weeks. He was unable to repeat number due to his defective STM although he could recall items if he read them than than them being spoken aloud to him.