Developmental trends in utilizing perceptual closure for grouping of shape: Effects of spatial proximity and collinearity

Time course of grouping of shape by perceptual closure: Effects of spatial proximity and collinearity

“…The present results also converge nicely with previous results with adults in a visual search task (Hadad & Kimchi, 2006). Observers in Hadad and Kimchi's study searched for a concave target among a variable number of convex distractors.…”

“…These results suggest that it is the presence of collinearity that is responsible for the difference in priming effects produced by the noncollinear versus the collinear primes in the large-gap condition in Experiments 1 and 2, rather 30 746 724 765 743 815 797 790 749 80 719 715 751 745 804 817 773 731 180 743 723 733 747 804 806 767 760 380 758 739 760 753 816 815 747 771 680 755 729 762 740 801 789 741 The present results are generally consistent with the idea that perceptual closure is not an all-or-none phenomenon but rather a continuum (Elder & Zucker, 1993, 1994Gillam, 1975;Hadad & Kimchi, 2006). However, the present results also show that the efficiency of grouping fragments into a shape by closure depends critically not only on the size of the gaps between the closure-inducing fragments, but also on the distribution of the gaps along the contours.…”

“…For example, Kimchi (1998;Kimchi et al, 2005) showed that the rapid and effortless grouping of many small elements and the individuation of few large elements mature at a relatively early age, whereas the time-consuming and effortful grouping of few large elements and the individuation of many small elements develop with age. The present findings, however, taken together with those of Hadad and Kimchi (2006), suggest that there is no necessary correspondence between the two time scales of perceptual organization. The present microgenetic findings indicate rapid grouping of shape by closure combined with collinearity, both when the closure-inducing lines are spatially close and when they are spatially distant.…”

“…Finally, a comparison between the present microgenetic results and the ontogenetic results of Hadad and Kimchi (2006) makes it possible to examine the relationship between microgenesis and ontogenesis of perceptual organization. A particular way of viewing the relation between these two time scales of visual perception was suggested by Werner (1948Werner ( , 1957.…”

Missing the big picture: impaired development of global shape processing in autism

“…However, studies with older children suggest that there is a protracted developmental trajectory for the ability to integrate local visual features spatially across the visual field [Hadad & Kimchi, 2006;Kovács, 2000;Kovács, Kozma, Feher, & Benedek, 1999]. In particular, several studies have reported that sensitivity to global structure in hierarchical visual stimuli, in which multiple levels of structure co-exist from the local elements to the global structure, is not fully mature even in late childhood and early adolescence [Burack, Enns, Iarocci, & Randolph, 2000;Dukette & Stiles, 1996;Enns, Burack, Iarocci, & Randolph, 2000;Mondloch, Geldart, Maurer, & de Schonen, 2003;Mottron et al, 1999;Porporino, Shore, Iarocci, & Burack, 2004].…”