Priming is not necessary for selective-attention failures: semantic effects of unattended, unprimed letters.

Abstract

Certain experimental effects indicate that unattended stimuli are sometimes processed semantically (e.g., B. A. Eriksen & C. W. Eriksen, 1974; Stroop, 1935). Previously, such effects have been demonstrated primarily in situations in which the identities of the unattended stimuli would have been primed by task relevance, and it is possible that such priming is necessary for unattended stimuli to be processed semantically. Six experiments examined the importance of such priming in the selective-attention paradigm of Eriksen and Eriksen. (1974). Subjects classified target letters presented in the relevant center position of a three-letter visual display, ignoring simultaneously presented irrelevant flanker letters on each side of it. Across trials, identities of the flankers were correlated with, and therefore predictive of., correct responses. Although subjects had been instructed to ignore the flankers and later seemed to have no awareness of their correlation with responses, response times indicated that subjects learned and were influenced by the predictive relationship of the flanker to the response. This effect provides an example of semantic processing of unattended stimuli that have not been primed by either task relevance or long-term relevance. It is also of interest as an example of associative learning that is both incidental and apparently unconscious.