Effects of noise letters upon the identification of a target letter in a nonsearch task

Abstract

During a I-sec tachistoscopic exposure, Ss responded with a right or left leverpress to a single target letter from the sets Hand K or Sand C. The target always appeared directly above the fixation cross. Experimentally varied were the types of noise letters (response compatible or incompatible) flanking the target and the spacing between the letters in the display. In all noise conditions, reaction time (RT) decreased as between-letter spacing increased. However, noise letters of the opposite response set were found to impair RT significantly more than same response set noise, while mixed noise letters belonging to neither set but having set-related features produced intermediate impairment. Differences between two target-alone control conditions, one presented intermixed with noise-condition trials and one presented separately in blocks, gave evidence of a preparatory set on the part of Ss to inhibit responses to the noise letters. It was concluded that S cannot prevent processing of noise letters occurring within about 1 deg of the target due to the nature of processing channel capacity and must inhibit his response until he is able to discriminate exactly which letter is in the target position. This discrimination is more difficult and time consuming at closer spacings, and inhibition is more difficult when noise letters indicate the opposite response from the target.

The effect of additional characters on choice of referring expression: Everyone counts☆

“…This idea is consistent with evidence from the attention literature that unattended or irrelevant stimuli are processed (e.g., Mack & Rock, 1998) and can compete for resources (Eriksen & Eriksen, 1974;Stroop, 1935). The results of Experiment 2 further localized this effect to the presence of two characters in the discourse rather than their visual presence in the scene being described.…”

Aerobic fitness and cognitive development: Event-related brain potential and task performance indices of executive control in preadolescent children.

“…Participants completed congruent and incongruent conditions of the Eriksen flanker task (Eriksen & Eriksen, 1974), which required them to respond as quickly as possible to an array of letters presented on a computer monitor from a distance of 1 m with visual angles of 1.7° and 3.7° in the vertical and horizontal directions, respectively. The stimuli were 7.62-cm-tall white letters presented focally on a black background in a random order for 200 ms with an interstimulus interval of 1,200 ms from stimulus offset to onset.…”

The CODE theory of visual attention: An integration of space-based and object-based attention.

“…However, the fuzziness lies in different parts of the system. Spacebased theories of attention assume that the boundary of the sampled region--the edge of the spotlight--is fuzzy (e.g., Eriksen & Eriksen, 1974;Eriksen & Hoffman, 1973). This idea is explicit in LaBerge and Brown's (1989) gradient theory.…”

“…High discriminability produces big spotlight beams and low discriminability produces small ones, consistent with the data and with theorists' speculations. Eriksen and Eriksen (1974) published an important article on which much of the debate over space-based and object-based attention was grounded. They showed that people were influenced by distractor items that flanked the target even when there was no uncertainty about target location.…”