long term memory (ltm)

summaris Bahrick et al. (1975):

• US graduates shown classmate photos years after graduation

• 90% accuracy for remembering names and faces 34 years after graduation

• declined after 48 yeras (particularly for faces)

how can LTM be divided?

LTM → explicit + implicit LTM:

• explicit LTM → episodic + semantic LTM

• implicit LTM → procedural LTM

what is explicit LTM?

LTM that is declarative and conscious

what is implicit LTM?

LTM that is non declarative and unconscious

what is episodic LTM?

LTM involving timestamped and detailed episodes from one’s own life

what is semantic LTM?

LTM of facts/general knowledge

what is procedural LTM?

LTM concerning how to do things (require practice but automatic once learned)

describe the clinical case study of Clive Wearing:

• contracted a virus of the brain, damaging his LTM but not affecting his STM

• e.g. remembered how to play the piano: procedural, but not that he could: episodic

how is the clinical case study of Clive Wearing evidence against the MSM/evidence for LTM?

• retained procedural memory (how to play the piano) but not episodic (that he could play the piano)

• suggests MSM is wrong to suggest LTM is a single store

how is the clinical case study of Clive Wearing evidence to support the MSM?

• LTM damaged, but not STM

• reinforced the idea that STM and LTM are different stores

describe the clinical case study of HM:

• HM suffered from epilepsy and so had surgery to remove his hippocampus

• after surgery: STM remained same, LTM memory retained from before surgery, but could not make any more LT memories

how is the clinical case study of HM evidence to support the MSM?

• HM could not make any more LT memories, suggesting the link between STM and LTM had been broken

• demonstrated that memories have to pass through STM to get to the LTM

how is the clinical case study of HM evidence against the MSM/evidence for LTM?

• HM retained procedural memory of skills he had learned but had no episodic memory of learning the skills

• suggests MSM is wrong to suggest LTM is a single store

name and explain one limitation of LTM:

conflicting research linking types of LTM to areas of brain → challenges neurophysical evidence:

• Buckner and Petersen (1996): LHS of prefrontal cortex: semantic memory, RHS of prefrontal cortex: episodic memory

• Tulving et al. (1994): LHS of prefrontal cortex: encoding of episodic memory, RHS of prefrontal cortex: episodic retrieval