Selective attention and its maintenance in children : a developmental study
This study explored age trends in the maintenance of attention to rapidly presented visual stimuli and the effects of irrelevant information on this ability. It also investigated age differences in selective attention to stimuli differentiated in terms of "figural" or object quality. Children at each of ages 5, 7, and 10 years viewed films of briefly exposed and rapidly presented stimuli. They were instructed to identify assigned targets by pressing a response button. The tasks were systematically varied with respect to both the presence/absence of irrelevant information and certain target/distractor characteristics. Two types of stimuli (line drawings of familiar juvenile objects and commercially-produced decorative border tapes) and two distraction conditions (stimuli presented alone and with irrelevant information) were combined in preparing four films which were each five minutes long. The films consisted of rapidly-paced sequences of items containing (a) pictures alone, (b) borders alone, (c) pictures with irrelevant borders, and (d) borders with irrelevant pictures. Overall accuracy of target identification as well as the consistent maintenance of attention over time on the tasks improved with increasing age, were generally better without than with irrelevant information, and were more often better when the target was more prominent (pictures). Developmental differences, however, also occurred. Ten-year-olds at tended accurately and maintained an accurate level of performance under selective as well as non-selective conditions wzith few exceptions. Seven-year-olds also attended to pictures with irrelevant borders as well as they did to pictures alone; but they attended less accurately to borders, more so wzith distraction than without it. Preschool children performed least accurately. Their performance was impeded by distraction regardless of target type; but there was seme evidence that they could attend selectively, articularly at the outset of the easier picture target task. On most of the tasks, however, the scores of the preschool children fell off considerably over time. Developmental differences in the effects of irrelevant information on performance were also greater on the more difficult border identification task, but these differences occurred regardless of either absolute or proportional data were considered. The results were interpreted in terms of the development of (a) more highly structured visual models, (b) anticipatory schemata, and (c) less dependence on stimulus arrangements or continuously available information.