A 'trigger' of information that allows us to access memory. Such cues may be meaningful or may be indirectly linked by being encoded at the time of learning. Indirect cues may be external or internal.
Tulving reviewed research into retrieval failure and discovered a consistent pattern to the findings. He summarised this pattern in what he called the encoding specificity principle.
This states that a cue has to be both 1) present at the encoding and 2) present at retrieval. If the cues available at both encoding and retrieval are different then there will be some forgetting.
Some cues are encoded at the time of learning in a meaningful way, such cues are used in many mnemonic techniques.
Research on context-dependant forgetting: Godden and Baddeley - procedure
Studied deep-sea divers who work underwater to see if training on land helped or hindered their work underwater. The divers learned list of world either underwater or on land and recall either underwater or on land.
Research on context-dependant forgetting: Godden and Baddeley - findings and conclusions
In two of these conditions the environmental contexts of learning and recall matched, whereas in the other two they didn't. Accurate recall was 40% lower in the non-matched conditions.
They concluded that the external cues available at learning were different from the ones available at recall and this lead to retrieval failure.
Research in state-dependant forgetting: Carter and Cassaday - procedure
Gave antihistamine drugs (for hay fever) to their ppts. The drugs had a mild sedative effect making the ppts slightly drowsy. This creates an internal psychological state different from the 'normal' state of being awake and alert. Ppts had to learn list of words and recall them in one of the conditions:
There's a range of research that supports the retrieval failure explanation.
The studies by Godden and Baddeley and Carter and Cassaday are just two examples because they show that a lack of relevant cues at recall can lead to context-dependent and state-dependent forgetting in everyday life.
Eysenck and Keane argue that retrieval failure is perhaps the main reason for forgetting from LTM.
This evidence shows that retrieval, failure occurs in real-world situations as well as in highly controlled conditions of the lab.
Evaluation: Recall versus recognition (limitation)
Context effects may depend substantially on the type of memory being tested.
Godden and Baddeley replicated their underwater experiment but used a recognition test instead of recall - ppts had to say whether they recognised a word read to them from a list, instead of retrieving it for themselves.
When recognition was tested there was no context-dependent effect, performance was the same in all four conditions.
This suggests that retrieval failure is a limited explanation for forgetting because it only applies when a person has to recall information rather than recognise it.