Waugh and Norman- serial probe, doesn't support
Peterson and Peterson - trigrams, 18-30 secs
Difficult to test trace decay as if participants are tested after a different time period, they could be rehearsing and thus, strengthening the trace, but if rehersal is prevented by a distractor task, it could be due to Interference from the task, not decay
Trace decay doesn't explain why people rememeber stuff later as if it decays it should never be avaliable
Peterson and Peterson can be used as evidence for the role of decay in stm
Waugh and Norman set out to support trace decay but the results were better explained by interference
Waugh and Norman - supports, serial probe
Adequate when applied to the MSM.
Primary recency supports the theory
But more findings have suggested the memory is more complex than the MSM
Baddeley and hitch - rugby players
Keppel and underwood- trigrams
Ltm - mcgeoch and McDonald
EVAL- most support comes from lab studies and use nonsense syllables. When more meaningful info is used, interference is more hard to demonstrate (Solso)
Situations it deals with are rarely in real life and in the lab learning takes place in a very short amount of time which makes it more likely for interference to occur and so lack ecological validity
Studies have largely involved episodic memory, and although this shows episodic memory may be subject to interference, semantic memory may be more resistant
Lack of consolidation
Yarnell and lynch - American footballers
Patients who've been concussed often suffer retrograde amnesia, which is loss of memory for events prior to the acident. This could be due to the interruption of the consolidation process
Electro-compulsive (ECT) therapy causes memory loss for events prior to therapy and evidence suggests a one hour delay between learning and ect, perfect retention occurs, suggesting the consolidation period is up to one hour.
Godden and Baddeley - divers
Evaluation- retrieval failure explains findings that can't be explained by trace decay and there's alot of evidence supporting it. However some has been criticised, such as many have been carried out under extreme conditions, such as deep sea divers, or where states are very different (mood manipulation) where in real life we don't have to recall things under extreme conditions.
This therefore lacks ecological validity and in less dramatic changes in environment, only slight differencs are produced ( BADDELEY 1995)
Glucksberg and Lloyd - electric shocks
In order to investigate motivated forgetting, participants would have to experience something traumatic and this is unethical. But where mildly traumatic experiences have been investigated, evidence has been found for repression
Support for motivated forgetting is also evident in tests of emotional inhibition, eg, levinger and Clark found participants were particularly poor At remembering words associated To emotion.
However, more recent studies have found it might not be repression but arousal that influences the recall of words. Although emotionally charged words are unlikely to be recalled straight after learning, evidence found that when participants are tested after a delay of seven days or more, the opposite results are found, and the emotional words are better recalled. This can't be explained by repressive forgetting but can by arousa. This theory proposes high arousal inhibits immediate recall but leads to better recall in the long term.
Which is which
Stm - decay/ displacement
STM and ltm - interference/decay
Ltm- lack of consolidation, interference, retrieval failure and motivated forgetting