Long term memory

• What is the capacity of LTM?

  unlimited
• evidence for capacity of LTM:

  Anokhin 1973: he concluded that no human yet exists who can use all of the potential of their brain, the capacity of LTM is limitless.
• What is the duration of LTM?

  unlimited
• Evidence for the duration of LTM

  Bahrick et al (1975): asked 392 ppts to recall names from class mates in high school from 50 photos.
• (duration) 15 years after graduation what percentage was free recall?

  60%
• (duration) 48 years after graduation what was the free recall?

  30%
• (duration) after 15 years what was the percentage of recognition?

  90%
• (duration) What was the percentage of recognition after 48 years?

  70%
• What did Bahrick et al conclude in their duration study?

  LTM can have a potentially unlimited duration, some memories need assistance to be retrieved.
• What is a strength of STM+LTM?

  High control over variables —> controlled environment —> can be retested increases internal validity.
• What is a weakness of STM+LTM?

  High in demand characteristics —> artificial environments —> ppts guess aims of research —> lowering internal validity.