The influence of enactment on short-term recognition

In three experiments subjects worked on a short-term memory recognition task (Sternberg Paradigm) with verbs. In Experiment 1 nouns were used in addition. Half of the verbs were encoded by a verbal learning task (VT), and the other half by a subject-performed task (SPT). With SPTs, subjects were required to perform the actions denoted by the verbs during study. With SPT, in Experiment 1 each verb of the memory set was performed and in Experiments 2 and 3 only a single verb of each list was performed, making this item unique. All encoding conditions showed set-size effects which did not interact with the type of encoding. Even response times on the single performed item of the set showed set-size effects, comparable in size to the other conditions. SPT did not change the slope of the reaction-time function over set size, but when the whole list had been performed subjects reacted more slowly in the SPT condition than in the VT condition, whereas when a single item was performed this item was recognised faster than the non-performed items. We conclude (a) that SPT does not influence memory entries in verbal short-term memory, (b) that the set-size effect has its origin in the access to the memory entry of the target based on the surface information of the words, and (c) that the effect of having performed the item is effective after this access to memory.