More modality effects in the absence of sound.

Two experiments examined serial recall of lists containing random orderings of the digits, 1, 2, 3, and 4. Our intention was to demonstrate active and passive modality effects with silently presented tactile input. In Experiment I, recency recall was enhanced relative to a visual control when subjects received list input by placing their palms on wooden blocks containing 1, 2, 3, or 4 vertical pegs. In Experiment 2, subjects produced their own tactile input by pressing their thumb and first, second, third, or fourth finger together to signify visual digits presented on a CRT. Recency was enhanced with the added tactile input relative to a visual-only control. The relation between these results and current theories of the modality effect is discussed. A new interpretation of the modality effect is presented. For a number of years, memory researchers have attempted to explain why auditory presentation produces better recency performance during immediate serial recall than visual presentation (Conrad & Hull, 1968). Explanations of this "modality effect" have typically appealed to the inherent superiority of auditory traces, most notably, the greater durability of auditory sensory memory compared with visual sensory memory (e.g., Crowder & Morton, 1969). However, recent data from a number of laboratories indicate that sensory memory theories of the modality effect are no longer capable of explaining the data pattern. This research has shown that there are a number of ways of producing the bow-shaped serial recall curves that are characteristic of auditory stimulation. For example, memory for silently lip-read input shows marked recency relative to the recall of static visual input (e.g., digits presented on cards or by a CRT; Campbell & Dodd, 1980; Gardiner, Gathercole, & Gregg, 1983; Greene & Crowder, 1984). Second, recency is improved when subjects silently mouth digits shown on a screen rather than merely read them (Greene & Crowder, 1984; Nairne &