Disruption of Verbal Stm by Irrelevant Speech, Articulatory Suppression, and Manual Tapping: Do they have a Common Source?

Abstract

Under appropriate conditions, immediate serial verbal recall is impaired by irrelevant speech, articulatory suppression, and syncopated tapping. Interpretation of these variables in terms of the phonological loop component of working memory assumes separate phonological storage and articulatory rehearsal processes. In contrast, the Object-Oriented Episodic Record (O-OER) of Jones and the feature theory of Neath interpret these and other phenomena in terms of a unitary multimodal system. Three experiments investigate these disrupting tasks, with each experiment emphasizing one parameter. In each case, recall of phonologically similar and dissimilar letter sequences is compared as a marker of the presence or absence of phonological coding. In Experiment 1, subjects heard or articulated a single item, or tapped a single key at equal intervals. Only articulatory suppression impaired performance; it also abolished the effects of phonological similarity. Experiment 2 was identical, except that items were heard, or generated in a syncopated rhythm. Both suppression and tapping impaired performance to an equivalent extent and obliterated the effect of phonological similarity. Syncopated irrelevant speech caused a modest but significant impairment in performance. Experiment 3 was identical to Experiment 1, except that six tokens were used. Irrelevant speech and tapping had a clear impact on recall, but neither removed the phonological similarity effect. Again articulatory suppression had a major impact on performance and removed the effect of phonological similarity. We conclude that the pattern of results readily fits the phonological loop hypothesis, provided one accepts Saitos proposal that generating syncopated sequences uses common processes with speech production. It is not clear how the results can be explained by either the O-OER or the feature hypothesis.

Phonological similarity in working memory span tasks

“…Consistent with this, the phonological similarity effect is not observed when phonological encoding and rehearsal is prevented via articulatory suppression (Larsen & Baddeley, 2003).…”

Is there brief temporal buffering of successive visual inputs?

“…The procedure for Experiment 6 was the same as that described for the main task of Experiment 3 with the exception that participants were required to rehearse aloud "bla-bla", during presentation of the stimuli (Larsen & Baddeley, 2003). They typically completed 7 to 9 clearly enunciated repeats of "bla-bla".…”

Repetition learning in the immediate serial recall of visual and auditory materials.

“…This has led some people, most notably Jones and colleagues in the context of their O-OER (Object-Oriented Episodic Record) model, to propose a unitary, amodal, ordered store which is involved in a functionally equivalent fashion in the retention of auditory, visual and spatial sequences (Jones, Farrand, Stuart & Morris, 1995;Macken & Jones, 1995). It is difficult, however, to reconcile this position either with the patterns of Hebb repetition learning 7 interaction seen in the data (see Larsen and Baddeley, 2003, and the accompanying discussion, for much more on this issue) or with the dissociations seen in the neuropsychological literature (Basso, Spinnler, Vallar, & Zanobio, 1982;Hanley, Young, & Pearson, 1991;de Renzi & Nichelli, 1975;Trojano & Grossi, 1995;Warrington & Shallice, 1969).…”