Constraints on awareness, attention, processing, and memory: some recent investigations with ignored speech.

We discuss potential benefits of research in which attention is directed toward or away from a spoken channel and measures of the allocation of attention are used. This type of research is relevant to at least two basic, still-unresolved issues in cognitive psychology: (a) the extent to which unattended information is processed and (b) the extent to which unattended information that is processed can later be remembered. Four recent studies of this type that address these questions in various ways (Cowan, Lichty, & Grove, 1990; Wood & Cowan, 1995a,b; Wood, Stadler & Cowan, in press) are reviewed as illustrations. We conclude from these studies that (a) unattended information appears to be partially processed automatically, though attention enhances the processing considerably, and (b) the unattended information that is processed may not be retrievable in direct or many indirect memory tasks, though it remains possible that there is an automatically stored memory trace (e.g., one that could produce semantic priming).