HM had his hippocampus taken out to stop his seizures (that started due to a head injury when he was seven years old), hence creating a unique group with a pre-existing condition.
Purpose
Study the effects of hippocampus loss, hence the role of the hippocampus on memory formation.
Method triangulation
Using multiple methods during the study.
Methods used
IQ testing (psychometric testing), direct observation, interviews (HM and family members), cognitive tests, MRI scans
Longitudinal
The study lasted for 50 years.
Results
Unable to make new episodic nor semantic knowledge but procedural memories, cognitive mapping and working memories (conversations) were still intact.
Results
Unable to make long term memory from short term memory (role of acetylcholine in the hippocampus - involved with memory formation).
Ethics
Not much prior data, not a lot of confidentiality, consent was blurred (they had to ask for it every day since he did not remember), unique and irreplicable case.
