Serial position effects in 2-alternative forced choice recognition: Functional equivalence across visual and auditory modalities.

Abstract

Two experiments examined Ward, Avons and Melling’s (2005) proposition that the serial position function is task, rather than modality, dependent. Specifically, they proposed that for backward testing the 2-alternative forced choice (2AFC) recognition paradigm is characterised by single-item recency irrespective of the modality of the stimulus presentation. In Experiment 1 the same nonwords sequences, presented both visually or auditorially, produced qualitatively equivalent serial position functions with 2AFC testing. Forward testing produced a flat serial position function, whilst backward testing produced two-item recency in the absence of primacy. In order to rule out the possibility that the serial position functions for visual stimuli were the product of sub-vocal rehearsal, Experiment 2 employed articulatory suppression during the presentation phase. Serial position function equivalence was again observed together with a modest impairment in overall recognition rates. Taken together, these data are consistent with the Ward et al. proposition and further support the existence of a visual memory that can facilitate storage of visual-verbal material e.g. Logie, Della Sella, Wynn, and Baddeley (2000). However, the observation of two-item recency contradicts the original Duplex account of single-item recency traditionally observed for backwards recognition testing of visual stimuli (Phillips and Christie, 1977).