Studies of recall and storage in shortterm memory.

Experiments were designed to measure the effects upon short-term
retention of verbal material of certain variables relating to (i) serial
organization and (ii) the activity of recalling.
In Section 1, some effects of sequential redundancy upon shortterm
verbal memory are described. It is shown that retention is positively
related to the similarity in structure of the material to language. A series
of experiments was carried out, using sequences of both word and letter units,
in order to provide information about the stage or stages within a memory
task at which sequential redundancy is directly influential. It has been
suggested that sequential organization has its main influence at the time
of recall. The present results indicate that this is incorrect, and show
that memory is already affected by redundancy in a sequence at a stage prior
to the recall of verbal items.
Section 2 is concerned more directly with effects of the activity
of recalling verbal material. An experiment is described which shows that
accuracy of reproduction may be related to order of recall, the first items
to be recalled in a short-term memory task being more accurately reproduced,
on the whole, than those recalled later. Consolidation in the storage of
items is found to be related to the order of presentation. Some experiments
are described which aimed to explain these results, and it is concluded that
both rehearsal and storage time contribute to consolidation in short-term
memory. The result of a further experiment confirms the observation that
verbal items B.re sometimes most accurately reproduced when recalled in an
order different from that in which they were presented.