Evidence of both perceptual filtering and response suppression for rejected messages in selective attention.

In 10 replications of the same design (N = 165), 5s rapidly named series of digits presented in a focal channel (visual for Replication I-VIII, auditory for Replication IX-X) while hearing simultaneous distracting digits (dichotic presentation in Replication IX-X). Rate of stimulus presentation was varied in the range from 1 trial/1 sec to 1 trial/4 sec. In 5 of the 10 replications, mostly those using the slower stimulus presentation rates, conflict due to distractors was reduced when the same digit was repeated for several trials in the distractor channel. Of these 5 replications,'evidence for both perceptual filtering prior to verbal analysis of distractor content and suppression of responses to the distractor was obtained in 4. These and other results indicated that the nervous system may (a) limit perceptual analysis of verbal distractor sequences that are either random or predictable and (b) suppress verbal responses that tend to be elicited by predictable distractors. These perceptualfiltering and response-suppression processes apparently function best at relatively slow stimulus input rates.