PRONUNCIABILITY AND REHEARSAL TIME IN SHORT-TERM MEMORY WITH CONTROLLED ACQUISITION

144 undergraduates attempted to memorize visually presented sequences of 3 trigrams that were either easy (E-Pr) or difficult (D-Pr) to pronounce. After being equated for performance at a 0-sec retention interval, Ss received trials composed of presentation of the trigrams, a rehearsal period of 0, 5, or 10 sec., and a retention period of 0, 5, or 10 sec. S was uninstructed regarding the rehearsal period and was engaged in backward counting during the retention period. The average exposure time required to equate performance at a 0-sec retention interval was about 10 times as long for the D-Pr material as for the E-Pr material. At the 0-sec level of rehearsal the retention functions for the E-Pr and D-Pr material began at the same point and then diverged, with performance for the E-Pr material the lower. At the 5- and 10-sec levels of rehearsal the retention curve for the E-Pr material rose above that of the D-Pr material and the divergence disappeared. For both E-Pr and D-Pr material, rehearsal had the effect of flattening the retention functions. (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1969 American Psychological Association.