Estimating the Capacity of Phonological Short-term Memory

Abstract

Two methods of assessing the capacity of phonological short-term memory that minimize support from long-term memory were compared in a sample of 7- and 8-year-old children. The children were tested on immediate serial recall of words and nonwords, and on the serial recognition of sequences composed of words and nonwords. Serial recognition scores were found to be highly related to children's accuracy of recall of nonwords composed of low-probability phonotactic combinations, but were independent of the long-term memory contributions to recall estimated in the serial recall experiment. Children with high vocabulary knowledge performed significantly better than low vocabulary children on both the recall and recognition measures. It is argued that the convergence of the two techniques lends substantial validity to their use as assessments of phonological storage capacity relatively free of long-term memory influence, and that the crucial difference between children varying in vocabulary knowledge lies in this storage capacity rather than the differential availability and use of long-term knowledge. Deux methodes permettant d'evaluer la capacite de la memoire a court terme phonologique en minimisant la contribution de la memoire a long terme (MLT) ont ete comparees chez des enfants de 7 et 8 ans. Une tache de rappel seriel ainsi qu'une tache de reconnaissance serielle de mots et de non-mots ont ete utilisees. Les resultats montrent que les scores de reconnaissance serielle sont fortement relies a la capacite de rappeler des non-mots, mais qu'ils sont independants des contributions de la MLT. La performance des enfants ayant une bon vocabulaire etait plus elevee aux mesures de rappel et de reconnaissance. Il est propose que la convergence des deux techniques donne une validite substantielle a leur utilisation afin d'evaluer la capacite d'emmagasinage phonologique exempte des influences de la MLT. De plus, les resultats suggerent que les differences observees dans la connaissance du vocabulaire chez les enfants resident dans la capacite d'emmagasinage plutot que dans une difference au niveau de la disponibilite et de l'utilisation des connaissances en memoire a long terme.