Memory revision - Paper 1

SHORT TERM MEMORY

ENCODING - Mainly acoustic, Baddeley (four word lists)

CAPACITY - 7+-2 (Miller) - Jacobs (serial digit span or numbers and letter)

DURATION - 18-20 seconds Petersom&Peterson (trigrams of consonants)

RESEARCH FOR SHORT AND LONG TERM MEMORY

Glanzer and Cunitz: Showed when participants are presesnted with a list of words they tend to remember the first few and the last few rather than those in this middle - this is the serial position effect

This supports the existence of seperate short and long term memory stores. Effect = Primacy and Receny. First words shown were put into long term because participants had time to rehearse them - Primacy. Words from the end were still being stored in the short term memory so they were able to recall them - Recency.

Patient KF's Long term memory was unaffected but was only able to recall recent Short term memory items.

BADDELEY 1966 - Baddeley conducted a lab experiement in which participants were shown 4 lists of words. Semantically similar/ dissimilar and acoustically similar/ dissimilar. To test short term memory the list rememberd had to be recalled immediatley. To test long term memory words were recalled after an interval period of 20 minutes.

After immediate recall they tended to do worse with acoustically similar words which suggests that short term memory codes acoustically. After a timed interval of 20 minutes recall was worse with semantically similar words which suggests that Long term memory codes semantically.

One disadvantage of this study is that it has low ecological validity because people don't recall word lists in everyday life so we cannot generalise the findings to the wider population

Another disadvantage is that it uses artifical stimuli which lack meaning so we should be cautious when generalising the findings to different types of memory tasks, so this study has limited application.

One last disadvantage is that it fails to understand why songs can be encoded in the Long term memory acoustically without any consideration of meaning.

JACOBS - Jacobs conducted a lab experiement in which a sequence of digits that participants were shown had to be recalled in the correct order. The number of digits was increased until participants could no longer remember. Recall was immediate and on average participants could remember 9.3 numbers but only 7.3 letters.

He concluded that STM has a capacity between 5 and 9 (7+-2)

One disadvantage of this study is that it lacks validity because it was conducted a long time ago and may have lacked adequate control - For example participants may have become distracted and therefore under performed. So confounding variables may affect the validity of this study.

One strength is that findings have been usefully applied to improving memory and amounts people can store via chunking.

PETERSON&PETERSON - Conducted a lab experiment on 24 psychology students. Participants had to recall trigrams of consonants and then person an interference task to prevent rehearsal by counting backwards from different interval times of…