Functional characteristics of the inner voice and the inner ear: Single or double agency?

Abstract

Double agency theories of short-term memory posit the functional independence of a phonological store (inner ear) and articulatory process (inner voice). A series of 5 experiments challenges this view. Articulatory suppression during retention of 9-item lists gives rise to a changing-state effect similar to that shown for irrelevant speech. Also, vocalized suppression is more disruptive than silently mouthed suppression, but this difference arises from vocalization itself rather than from any auditory feedback to which it gives rise. Class similarity between the to-be-remembered items and the articulatory material is not a critical determinant, but the effect occurs only with tests of serial order. For mouthed suppression, the irrelevant speech effect is only attenuated with changing-state suppression. Also, the presence of changing-state irrelevant speech abolishes the changing-state effect of articulatory suppression. Functional equivalence of codes from auditory, visual, and articulatory sources is claimed.

What limits working memory capacity?

“…This prediction is borne out by the heterogeneity benefit (B6; Conlin et al, 2005;Conlin & Gathercole, 2006;Li, 1999;Turner & Engle, 1989; but see Macken & Jones, 1995).…”

“…For instance, memory for lists of digits is impaired more by concurrent processing of numbers than of words, whereas memory for lists of words is disrupted more by concurrent processing of words than of numbers (Conlin, Gathercole, & Adams, 2005;Li, 1999;Turner & Engle, 1989; for a partial exception to this pattern see Macken & Jones, 1995). Similarly, recall of lists of words is disrupted more by processing of other words than by processing of nonwords, whereas recall of lists of nonwords is disrupted more by processing other nonwords than by processing of words (Conlin & Gathercole, 2006).…”

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

“…Whatever these systems are doing when access to the loop is denied, the general patterns seen in the relevant ISR data, as reflected in serial position curves indicating characteristic primacy and recency advantages, are rather similar to those that result from loop access. 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).…”

Articulatory suppression and the irrelevantspeech effect in short-term memory: Does the locus of suppression matter?

“…The deleterious effect of suppression usually is greater than that of IS (e.g., Salamé & Baddeley, 1982) and is greater when participants pronounce multiple irrelevant items (changing-state suppression), as opposed to repeatedly articulating a single irrelevant item (steady-state suppression; e.g., Macken & Jones, 1995).…”

“…Macken and Jones (1995) required suppression only during a postinput retention interval or "rehearsal phase," in which participants articulated silently. In contrast, Hanley (1997) and Baddeley (1982, 1987) required suppression during the input phase of each trial, in which the irrelevant articulation was vocalized.…”