Abstract
Introduction. Previous work shows a decline in selective attention but intact feature integration in healthy elderly adults using a novel visual search paradigm that manipulates the demands on dorsal-ventral visual stream interactions (Heindel, Festa et al., 2009). However, the relationship between selective attention and feature integration has not been examined in childhood, during which time selective attention typically improves. Here we ask whether feature integration demands disrupt children's visual search performance, and whether this demand increase is modulated by selective attention efficiency. Methods. Children (N=42; 5-9 years) searched for a vertically moving target among vertically and horizontally moving distractors. We manipulated both target feature and set size. Targets were either black (motion-luminance condition) or red (motion-color condition) and distractors were either black and white, or red and green, respectively. Targets were presented among either two or four distractors. The motion-luminance and motion-color conditions placed minimal and maximal demands on cross-cortical interactions, respectively. Feature salience and search demands were matched across conditions. Thus, reaction time differences between feature conditions must be attributed to integration demands, while set size differences between conditions must be attributed to selective attention. Results. Preliminary results show that children were slower to find targets as set size increased [F(2,54)=198.20, p< .001]. While search time increased as set size increased in both feature conditions, search times did not differ between feature conditions when no distractors were present [F(1,41)=0.192, p=.66]. However, children were faster to detect luminance targets relative to color targets when either two [F(1,40)=4.376, p=.04] or four [F(1,40)=3.282, p=.08] distractors were present [feature by set size interaction: F(2,54)=3.682, p=.03]. Conclusion. Slower visual search on motion-color compared to motion-luminance trials suggests that cross-cortical feature integration may not fully develop until later childhood or early adolescence. Moreover, in childhood, greater feature integration demands may also increase attentional demands.
Meeting abstract presented at VSS 2018