Word-frequency and phonological-neighborhood effects on verbal short-term memory.

Immediate memory span and maximal articulation rate were assessed for word sets differing in frequency, word-neighborhood size, and average word-neighborhood frequency. Memory span was greater for high- than low-frequency words, greater for words from large than small phonological neighborhoods, and greater for words from high- than low-frequency phonological neighborhoods. Maximal articulation rate was also facilitated by word frequency, phonological-neighborhood size, and neighborhood frequency. In a final study all 3 lexical variables were found to influence the recall outcome for individual words. These effects of phonological-word neighborhood on memory performance suggest that phonological information in long-term memory plays an active role in recall in short-term-memory tasks, and they present a challenge to current theories of short-term memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Word-frequency effects on short-term memory tasks: evidence for a redintegration process in immediate serial recall

Four experiments investigated the mechanisms responsible for the advantage enjoyed by high-frequency words in short-term memory tasks. Experiment 1 demonstrated effects of word frequency on memory span that were independent of differences in speech rate. Experiments 2 and 3 showed that word frequency has an increasing effect on serial recall across serial positions, but Experiment 4 showed that this effect was abolished for backward recall. A model that includes a redintegration process that operates to "clean up" decayed short-term memory traces is proposed, and the multinomial processing tree model described by R. Schweickert (1993) is used to provide a quantitative fit to data from Experiments 2, 3, and 4.     

Sublexical or lexical effects on serial recall of nonwords?

S. E. Gathercole, C. R. Frankish, S. J. Pickering, and S. Peaker (1999) reported 2 experiments in which they manipulated phonotactic properties of nonword stimuli and observed the effects on serial recall. Their results show superior recall for items consisting of more frequent phoneme pairs (biphone frequency). Biphone frequency was counted as the number of 3 phoneme words in which the phoneme pair occurs. In the first experiment of the current article, the authors made the same manipulation while controlling for the number of lexical neighbors and found no effect of biphone frequency. In the second experiment, the authors manipulated neighborhood size while controlling biphone frequency and found a significant effect of neighborhood size. The authors argued that serial recall of nonwords is influenced by lexical rather than sublexical knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)