Research on duration - Duration of LTM

• Who conducted this research and when?

  Bahrick et al (1975)
• Procedure-

  - Studied 392 american participants aged between 17 and 74.

  - High school yearbooks were obtained from the participants or directly from some schools.

  - Recall was tested in various ways including: 1. photo-recognition test consisting of 50 photos, some from the participants high school yearbook. 2. free recall test- 2

  where participants recalled all the names of their graduating class
• Findings-

  Participants tested within 15 years of graduation were about 90% accurate in photo recognition. After 48 years, recall declined to about 70% for photo recognition. Free recall was less accurate than recognition - about 60% after 15 years, dropping to 30% after 48 years.
• Conclusion-

  This shows that LTM may last up to a lifetime for some material.