Long Term Memory

• Capacity of LTM is potentially unlimited
• Duration of LTM is potentially unlimited
• Encoding of LTM is semantic
• Semantic encoding is anything to do with meanings and concepts
• The LTM is made up of Explicit (declarative) memories and Implicit (unconsious) memories
• The Explicit memory is split into Episodic and Semantic memories
• The Implicit memory is split into Procedural memory and Emotional Conditioning
• Procedural Memory is responsible for knowing how to do things e.g motor skills
• Episodic memory is responsible for storing information about events that we have experienced
• Semantic memory is responsible for storing knowledge and concepts
• Bahrick investigated the duration of LTM using 392 high school graduates aged 17-74
• Bahrick split participants into 2 groups: Group 1 (recognition) were given a list of names and asked to select the name that matched a photograph, Group 2 (free recall) were asked to name the person in each photograph
• Results of Group 1: 90% at 15 years, 70% at 48 years
• Results of Group 2: 60% at 15 years, 30% at 48 years
• Bahrick concluded that the duration of LTM is potentially unlimited, and is more accurate when tested by recognition than by free recall
• Bahrick's study has higher external validity than similar studies using meaningless pictures, however did not control confounding variables e.g some people keeping in touch
• Baddeley concluded that encoding is semantic for LTM as the recall after 20 minutes for semantically similar words was 30% less accurate than for acoustically similar words