Short-term Memory - Psychology
...The Recency Effect A familiar example of the recency effect is the observation that a pop group is only as good as their last hit song. People remember things better if they have happened most recently. In relation to STM, the recency effect can be measured using free recall. This is where participants are shown a list of words or syllables, and asked to recall them in any order immediately after the list was presented. The recency effect is demonstrated by the fact that the last few items in the list are usually much better remembered than the items from the middle of the list. Glanzer and Cunitz (1966) found that counting backwards for only 10 seconds between the end of the list presentation and the start of the recall virtually eliminated the recency effect, but otherwise had no effect on recall. In other words, people could remember a similar number of words from earlier in the list but not the few at the end. This can be explained by the fact that the two or three words at the end list where in a fragile state (not well encoded) and therefor easily wiped out by the task of counting backwards (called an interference task because it interferes witht the process of creating a memory). In contrast, the other list items were in the long-term store, so were unaffected by the interference task. In Glanzer and Cunitz’s experiment the participants recalled the first few items much better than those in the middle of the list. This is known as the primary effect. Why is there a primary effect? The words at the start of the list are rehearsed more than those from the middle. This is shown by Rundus and Atkinson (1970), who asked their participants to rehearse out loud the words they wanted to during list presentation. The recency effect suggests that the capacity of about seven items. Why do these two techniques produce different results? One reason relates to different patterns of rehearsal. Participants carrying out the span task rehearse as many times as possible, where as those asked to learn a list for free recall rehearse only a few items at a time. The recency effect and span measures both indicate that the capacity of STM is strictly limited. In contrast, no effective limits on he capacity of LTM have been discovered. Duration in STM How long does STM last? this was demonstrated in an experim...