copding, capcity and duration (Bahrick’s et al 1975)

Aim

To find the duration of LTM

Procedure

392 Americans aged between 17 and 74 took part in 2 tests. One was recognition (50 faces in a yearbook) and the other was a free recall test (list names of graduating class)

Findings

Recognition: 90% accurate after 15 years, 70% after 48 years.

Free recall: 60% accurate after 15 years, 30% after 48 years

Strengths of Bahrick et al recall study

Meaningful memories were studied- high external validity (Lab studies with meaningless pictures have a lower recall rate-Shepard)

Weaknesses of Bahrick ET al (1975) LTM study

Lack of control- participants may have stayed in touch with high school students, therefore they may be extraneous variables= low reliability