A central capacity limit to the simultaneous storage of visual and auditory arrays in working memory.
If working memory is limited by central capacity (e.g., the focus of attention; N. Cowan, 2001), then storage limits for information in a single modality should apply also to the simultaneous storage of information from different modalities. The authors investigated this by combining a visual-array comparison task with a novel auditory-array comparison task in 5 experiments. Participants were to remember only the visual, only the auditory (unimodal memory conditions), or both arrays (bimodal memory conditions). Experiments 1 and 2 showed significant dual-task tradeoffs for visual but not for auditory capacity. In Experiments 3-5, the authors eliminated modality-specific memory by using postperceptual masks. Dual-task costs occurred for both modalities, and the number of auditory and visual items remembered together was no more than the higher of the unimodal capacities (visual: 3-4 items). The findings suggest a central capacity supplemented by modality- or code-specific storage and point to avenues for further research on the role of processing in central storage.
Saults
J Scott
JS
Department of Psychological Sciences, University of Missouri-Columbia, Columbia, MO 65211. USA. SaultsJ@missouri.edu
Cowan
Nelson
N
D000328:Adult; D001288:Attention; D001307:Auditory Perception; D001921:Brain / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology; D008570:Memory, Short-Term; D013997:Time Factors; D014796:Visual Perception