Articulatory and Phonological Determinants of Word Length Effects in Span Tasks

Abstract

Several previous studies have shown that memory span is greater for short words than for long words. This effect is claimed to occur even when the short and long words are matched for the number of syllables and phonemes and so to provide evidence for subvocal articulation as being one mechanism that underlies memory span (Baddeley, Thomson, & Buchanan, 1975). The three experiments reported in this paper further investigate the articulatory determinants of word length effects on span tasks. Experiment 1 replicated Baddeley et al.'s finding of an effect of word length on auditory and visual span when the stimuli consist of words that differ in terms of the number of syllables. Experiments 2 and 3 showed that the effects of word length are eliminated when the words in the span task are matched for the number of syllables and phonemes but differ with respect to the duration and/or complexity of their articulatory gestures. These results indicate that it is the phonological structure of a word and not features of its actual articulation that determines the magnitude of the word length effect in span tasks.

Theoretical Implications of Articulatory Duration, Phonological Similarity, and Phonological Complexity in Verbal Working Memory.

“…Given that the onset latency of an utterance may manifest speech-planning times (Rosenbaum, Gordon, Stillings, & Feinstein, 1987;cf. Sternberg et al, 1978), these results are inconsistent with Caplan et al's (1992) hypothesis and assumptions. cases in which articulatory duration and phonological complexity were confounded, and they dismissed the few cases in which these confounds did not occur (e.g., Experiment IV of Baddeley et al, 1975).…”

“…To support their hypothesis and assumptions, Caplan et al (1992) performed three experiments with various sets of words. Each experiment involved versions of the immediate serial recall task in which stimuli were presented either auditorily or visually, and responses were made with a "picture-pointing" procedure.…”

“…To support their claims, Baddeley and Andrade (1994) measured the articulatory durations for the words of the two sets in Caplan et al's (1992) Experiment 2. 4 These additional measurements were obtained by having participants rapidly repeat pairs of words 10 times, either overtly or covertly.…”

“…Caplan and Waters (1994). Caplan and Waters (1994) responded to Baddeley and Andrade's (1994) criticisms by repeating Experiments 2 and 3 from Caplan et al (1992). In this replication, 4 Only Caplan et al's (1992) Experiment 2 was addressed because the results of their Experiment 1 were not controversial, and the results of their Experiment 3 were not replicated subsequently by Caplan and Waters (1994).…”

“…Dashes indicate that corresponding statistics regarding the concreteness of these words were not reported. a Caplan et al (1992) reported the means and standard deviations for the written frequency of Word Sets 1-4.…”