Research On Capacity Stm Capacity Jacobs (1887)

Front 1

AIM

Back 1

To investigate the immediate span/ capacity of STM.

Front 2

METHOD

Back 2

Using the 'serial digit span technique' he developed.

Participants presented sequence of letters or digits, required to repeat back in same order as presented.

Presented participants with either sequence of letters or digits at regular intervals (every 1/2 second) asked to recall in same order.

Front 3

FINDINGS

Back 3

Participants recalled more digits than letters.

Average span for digits was 9.3 items and was 7.3 for letters.

Recall span also increased with age; 8 YEAR OLDS recalled an average of 6.6 digits and 19 YEAR OLDS recalled an average of 8.6 digits.

Front 4

CONCLUSIONS

Back 4

STM has limited capacity of between 5 & 9 items depending on age. Jacobs claimed the increase in STM span/ capacity due to increase brain capacity & individual ability to develop strategies to improve their memory such as chunking.

Front 5

EVALUATION OF JACOBS (1887)

Strength

Back 5

Study is lab experiment therefore establishes cause and effect.

Had high control over extraneous variables be confident that IV (the number of digits or letter) affected the DV (amount participants could recall)

Strength because results are reliable. Strongly supports idea that STM has limited capacity.

Front 6

EVALUATION OF JACOBS (1887)

LIMITATION

Back 6

However.. study was conducted a long time ago and thus lacks validity. Early research often lacked adequate control. EG. some participants may have been distracted while being tested so they didn't perform as they might.

This is a limitation cause results might of not been valid cause there were confounding variables that were not controlled.