Differences in real and illusory shape perception revealed by backward masking

Imber, Michelle L.; Shapley, Robert; Rubin, Nava

doi:10.1016/j.visres.2004.07.034

Cited by 18 publications

(11 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Given the rich and complex nature of human object recognition, it is likely that high-order object areas use both the individual features as well as a more holistic aspect that depends on their relative position. Such a representation is, in fact, compatible with fragment-based models (Epshtein & Ullman, 2005) and with the partial completion effects observed in the past (Lerner et al, 2004), as well as with the fMRI reports of holistic processing (Imber, Shapley, & Rubin, 2005;Altmann, Bulthoff, & Kourtzi, 2003;Kourtzi, Erb, Grodd, & Bulthoff, 2003;Stanley & Rubin, 2003).…”

Section: Discussionsupporting

confidence: 75%

Class Information Predicts Activation by Object Fragments in Human Object Areas

Lerner

Epshtein

Ullman

et al. 2008

Journal of Cognitive Neuroscience

View full text Add to dashboard Cite

Object-related areas in the ventral visual system in humans are known from imaging studies to be preferentially activated by object images compared with noise or texture patterns. It is unknown, however, which features of the object images are extracted and represented in these areas. Here we tested the extent to which the representation of visual classes used object fragments selected by maximizing the information delivered about the class. We tested functional magnetic resonance imaging blood oxygenation level-dependent activation of highly informative object features in low- and high-level visual areas, compared with noninformative object features matched for low-level image properties. Activation in V1 was similar, but in the lateral occipital area and in the posterior fusiform gyrus, activation by "informative" fragments was significantly higher for three object classes. Behavioral studies also revealed high correlation between performance and fragments information. The results show that an objective class-information measure can predict classification performance and activation in human object-related areas.

show abstract

Section: Discussionsupporting

confidence: 75%

Class Information Predicts Activation by Object Fragments in Human Object Areas

Lerner

Epshtein

Ullman

et al. 2008

Journal of Cognitive Neuroscience

View full text Add to dashboard Cite

show abstract

“…Our results showing younger children’s weakness to appreciate the global form in KIC patterns may suggest immature neural correlates in higher order visual areas (Gregory, 1972; Spillmann & Dresp, 1995; Imber, Shapley & Rubin, 2005), such as ventral stream visual areas involved in object processing (Mendola et al, 1999; Sary et al, 2008) and the lateral occipital complex (Stanley & Rubin, 2003; Wu et al, 2011). Although higher visual areas and global perception may develop in later childhood, younger children’s ability to process locally suggests intact and relatively early development of early visual areas, which are presumed to be involved in contour completion and may be used in focusing on the individual elements of an illusory contour (Lee & Nguyen, 2001; Maertens & Pollmann, 2005).…”

Section: Discussionmentioning

confidence: 69%

From local to global processing: The development of illusory contour perception

Nayar

Franchak

Adolph

et al. 2015

Journal of Experimental Child Psychology

View full text Add to dashboard Cite

Global visual processing is important for segmenting scenes, extracting form from background, and recognizing objects. Local processing involves attention to the local elements, contrast, and boundaries of an image at the expense of extracting a global percept. Previous work is inconclusive regarding the relative development of local and global processing. Some studies suggest that global perception is already present by 8 months of age, whereas others suggest that the ability arises in childhood and continues to develop in adolescence. We used a novel method to assess the development of global processing in 3-to 10-year-old children and an adult comparison group. We used Kanizsa illusory contours as an assay of global perception and measured responses on a touch screen while monitoring eye position with a head-mounted eye tracker. Participants were tested using a similarity match-to-sample paradigm. Using converging measures, we found a clear developmental progression with age such that the youngest children performed near chance on the illusory contour discrimination whereas 7-to 8-year-olds performed nearly perfectly, as did adults. There was clear evidence of a gradual shift from a local to a global processing strategy: Young children looked predominantly at and touched the pacman inducers of the illusory form, whereas older children and adults looked predominantly at and touched the middle of the form. These data show a prolonged developmental trajectory in appreciation of global form, with a transition from local to global visual processing between 4 and 7 years of age. KeywordsKanizsa illusory contours; perceptual development; global processing; eye tracking; global form perception Visual information about objects is often incomplete. Parts of objects can be occluded, missing, or blend seamlessly into the background, yet adults perceive the objects as complete global forms rather than a collection of disconnected local elements. In the laboratory, adults perceive holistic contours of shapes based on illusory edges that have no Author Manuscript Author ManuscriptAuthor ManuscriptAuthor Manuscript physical luminance, color, or texture boundary. How does this global perceptual ability come about? Although some researchers have found evidence for perception of illusory figures in young infants (e.g., Bertenthal, Campos & Haith, 1980;Kavsek, 2002;Otsuka & Yamaguchi, 2003;Bulf et al., 2011), others have reported that global form perception and discrimination of illusory shapes do not reach maturity until late childhood (Abravanel, 1982;Kimchi et al., 2005;Sherf et al., 2009;Hadad, Maurer & Lewis, 2010). Here, we used a novel approach-accuracy on a match-to-sample task paired with several measures of spontaneous manual and visual behaviors-to investigate the development of illusory contour perception as an assay of global form perception in children from 3 to 10 years of age. Our objective methods and converging behavioral evidence show a clear, protracted developmental program for global visual process...

show abstract

“…In an electrophysiological study (Murray, Imber, Javitt, & Foxe, 2006), when subjects discriminated relatable shapes from one another or non-relatable shapes from one another, the difference in VEP in these two cases (what was termed the "IC effect") obtained fast (124–186 ms) and regardless of whether subjects accurately discriminated the shape. It was also found that accuracy in a relatable condition correlated with neurophysiologic responses at 330–406ms post-stimulus onset, which was well after the IC effect (see also Imber, Shapley, and Rubin, 2005). Boundary completion was concluded to be early, automatic and dissociable from a later shape categorization stage—a view that fits nicely with our findings.…”

Section: Discussionmentioning

confidence: 66%

Is interpolation cognitively encapsulated? Measuring the effects of belief on Kanizsa shape discrimination and illusory contour formation

Keane

Papathomas

et al. 2012

Cognition

View full text Add to dashboard Cite

Contour interpolation is a perceptual process that fills-in missing edges on the basis of how surrounding edges (inducers) are spatiotemporally related. Cognitive encapsulation refers to the degree to which perceptual mechanisms act in isolation from beliefs, expectations, and utilities (Pylyshyn, 1999). Is interpolation encapsulated from belief? We addressed this question by having subjects discriminate briefly-presented, partially-visible fat and thin shapes, the edges of which either induced or did not induce illusory contours (relatable and non-relatable conditions, respectively). Half the trials in each condition incorporated task-irrelevant distractor lines, known to disrupt the filling-in of contours. Half of the observers were told that the visible parts of the shape belonged to a single thing (group strategy); the other half were told that the visible parts were disconnected (ungroup strategy). It was found that distractor lines strongly impaired performance in the relatable condition, but minimally in the non-relatable condition; that strategy did not alter the effects of the distractor lines for either the relatable or non-relatable stimuli; and that cognitively grouping relatable fragments improved performance whereas cognitively grouping non-relatable fragments did not. These results suggest that 1) filling-in effects during illusory contour formation cannot be easily removed via strategy; 2) filling-in effects cannot be easily manufactured from stimuli that fail to elicit interpolation; and 3) actively grouping fragments can readily improve discrimination performance, but only when those fragments form interpolated contours. Taken together, these findings indicate that discriminating filled-in shapes depends on strategy but filling-in itself may be encapsulated from belief.

show abstract

Differences in real and illusory shape perception revealed by backward masking

Cited by 18 publications

References 53 publications

Class Information Predicts Activation by Object Fragments in Human Object Areas

Class Information Predicts Activation by Object Fragments in Human Object Areas

From local to global processing: The development of illusory contour perception

Is interpolation cognitively encapsulated? Measuring the effects of belief on Kanizsa shape discrimination and illusory contour formation

Contact Info

Product

Resources

About