Three-year-old Children's Cognitive Flexibility on Dimensional Change Card Sorting Task: The Roles of Labeling and Nonverbal Stimuli in Working Memory

• Main Authors: Shiao-Han Ma, 麻筱涵
• Other Authors: 陳畹蘭
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/75697671456124416283

碩士 === 慈濟大學 === 人類發展學系碩士班 === 100 === People often persist in habitual behavior even when the behavior is currently inappropriate. This perseverative tendency suggesting the lack of cognitive flexibility is manifest not only in patients with frontal lobe lesions but also in children during the preschool years. The Dimensional Change Card Sorting (DCCS) task, in which children are required to sort cards first according to one dimension (e.g., shape) and then switch to the other dimension (e.g., color), has been found to be useful for studying cognitive flexibility in preschoolers. It has been shown that children younger than 4 years of age have difficulty switching dimensions on the DCCS task, even if they are clearly instructed to use the new rule each time before sorting a card. Executive functioning has been suggested to play a role in children’s perseverative response tendency on the DCCS task. However, there is much debate over which aspect of executive function primarily contributes to the development of cognitive flexibility, including cognitive complexity and conscious control accounts (Zelazo, Mueller, Frye, & Marcovitch, 2003), inhibition accounts (Diamond & Kirkham, 2005), and memory accounts (Munakata & Yerys, 2006). The purpose of the present study was to explore the role of working memory in 3-year-old children’s sorting behavior on the DCCS task. In a series of four experiments, we attempt to delineate the tendency to switch to a new rule in the post-switch phase by systematically reducing the phonological and iconic information encoded during pre-switch trials. In Experiment1 we translated the DCCS task into the Mandarin version and tested a sample of Taiwanese children aged from 2 to 4 (N = 48). The result revealed age-related differences, as were shown in previous research: 88% of the 4-year-old children successfully switched to sorting by a different dimension as contrasted to 0% and 20% of the 2- and 3-year-olds, respectively, who tended to produce peseverative errors. In Experiment 2, we devised a novel version of the DCCS task by using two different inkblots (one is red and the other is blue), and a generic label “Thing” to label each. The results showed that the 3-year-olds (N = 32) successfully switched from the shape dimension to the color dimension on this novel version. The success rate was 64% compared to 21 on the standard version In Experiment 3, the participants (N = 16) were allowed to label the inkblot stimuli themselves. When their labels were used to sort the nonverbal stimuli in the preswitch phase, they did not benefit from the noverbal feature of the inkblots in the postswitch trials. In Experiment 4, we followed the Experiment 2 procedure to label the verbal stimuli (i.e. rabbit vs. boat) comprising the standard DCCS generically as “Thing”. The 3-year-old (N = 16) children perseverated in the same rule during postswitch trials as they did in Experiment 1. While these findings suggest that the peseverative response tendency on the DCCS task is related to encoding resources in working memory, children do benefit from the generic label when nonverbal stimuli are sorted, which precludes the effect of automatic labeling cued by meaningful verbal stimuli.