The dark side of visual awareness in sport: Inattentional blindness in a real-world basketball task

Most research in the field of decision making in sports has focused on the bright side of visual attention and has not taken the dark side of visual awareness into account. Understanding the costs of such inattention should be complementary to the study of how attention facilitates perception. In the present study, we provide evidence for the existence of inattentional blindness (IB) in a real-world basketball setting among adults (Experiment 1). In Experiment 2, we found that players with hardly any basketball experience were more likely to experience IB in a real-world basketball setting, as compared with experienced athletes. Improving the ecological validity of the setting by enhancing the perception-action coupling (Experiment 3) and increasing task difficulty (Experiment 4) did not appear to affect the occurrence of IB among experienced athletes. IB can be considered a limitation of the visual system, but it also highlights a critical aspect of visual processing, which allows us to remain focused on the important aspects of the world. But as is shown in the present experiments, it is possible to induce an attentional set—for example, by sport-specific instructions—that leads to players’ missing important game-relevant information.     

Bottom-up and top-down dynamics in young children's executive function: Labels aid 3-year-olds’ performance on the Dimensional Change Card Sort

Executive function (EF) improves between the ages of 3 and 5 and has been assessed reliably using the Dimensional Change Card Sort (DCCS), a task in which children first sort bivalent cards by one dimension (e.g., shape) and then are instructed to sort by a different dimension (e.g., color). Three-year-olds typically perseverate on the pre-switch dimension, whereas 5-year-olds switch flexibly. Labeling task stimuli can facilitate EF performance (0110 and 0060), but the nature of this effect is unclear. In 3 experiments we examined 2 hypotheses deriving from different theoretical perspectives: first, that labels facilitate performance in a more bottom-up fashion, by biasing attention to relevant task rules (Kirkham et al., 2003); and second, that labels aid performance in a more top-down fashion by prompting reflection and an understanding of the hierarchical nature of the task (Zelazo, 2004). Children performed better on the DCCS when labels referred to the relevant sorting dimension (Experiment 1). This was a function of the content of the labels rather than the change in auditory signal across phases (Experiment 2). Furthermore, labeling the opposite dimension only did not have a symmetrically negative effect on performance (Experiment 3). Together, these results suggest external, verbal labels bias children to attend to task-relevant information, likely through interaction with emerging top-down, endogenous control.     

Adult Age Invariance in Sentence Unitization

We examined age differences on a letter detection task that was performed on four-word sentences in order to examine how letter-level and word-level processing is integrated with sentence-level unitization. Sentence-level unitization is defined as the formation of a sentence-level code that delays access to letter-level or word-level codes. There was a consistent word-frequency disadvantage for both age groups in which it took longer to detect letters within high and medium high frequency words than in low frequency words. This finding suggested that word-level and letter-level input channels were involved in a parallel “horse race” to the central processor while simultaneously outputting codes to the sentence-level at the second tier of processing. The present data also revealed that both age groups showed a larger relative increase in reaction time for letter detection for the fourth word position compared to the third word position on syntactically “intact” sentences relative to syntactically “scrambled” sentences. These data indicated that both age groups formed sentence-level codes that made letter-level codes more difficult to access. Finally, older adults' data showed a larger cost than younger adults' data for scrambled sentences than for intact sentences. These results suggest that older adults are more reliant on a syntactical processor that facilitates the parafoveal preview during the reading of syntactically intact sentences. These data suggest that whereas there are age differences in the perceptual processing of letters and words, sentence unitization and syntactical processing remain intact with increasing adult age.     

The Visuomotor System Resists the Horizontal-Vertical Illusion

The effect of the horizontal-vertical illusion on the visual and visuomotor systems was investigated. Participants (N = 8) viewed horizontal and vertical lines in an inverted-T stimulus and judged whether the two line segments were the same or different lengths. Participants also reached out and grasped either the vertical or the horizontal line segment of the stimulus. Perceptually, participants succumbed to the illusion; that is, they judged Ts of equal horizontal and vertical line lengths to be different and Ts of unequal line lengths to be the same. When reaching toward the same stimuli, however, the size of their grip aperture was scaled appropriately for the various line lengths. Thus, whereas the perceptual system succumbed to the illusion, the visuomotor system did not. Those results support a model proposed by M. A. Goodale and A. D. Milner (1992), who posited separate cortical pathways for visual perception and visually guided action.