Representation of possible and impossible objects in the human visual cortex: Evidence from fMRI adaptation

Freud, Erez; Ganel, Tzvi; Avidan, Galia

doi:10.1016/j.neuroimage.2012.08.070

Cited by 20 publications

(10 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Specifically, similar Garner interference effects (i.e., worse performance in a classification task of a given object’s dimension when an irrelevant dimension is varied; Garner and Felfoldy, 1970 ) was found for possible and impossible objects, suggesting that the two object categories were processed in a holistic fashion ( Freud et al, 2013a ). Additionally, in fMRI studies, similar adaptation patterns were found for possible and impossible objects ( Habeck et al, 2006 ; Freud et al, 2013b ).…”

Section: Introductionsupporting

confidence: 60%

“…Yet, differences in performance were also found between possible and impossible objects, with overall longer reaction times for impossible objects. Previous studies from our lab already showed that possible and impossible objects share similar a initial processing scheme ( Freud et al, 2013a , b ). In Experiment 1 we validated and extended these findings using a different, well-established paradigm of object-based attention.…”

Section: Discussionmentioning

confidence: 83%

“…Possible and matched impossible objects were identical except for one (Figure 1A ) or two features (Figures 1B,C ) inserted to make the object’s global 3D structure impossible. All pairs were used in previous experiments ( Freud et al, 2013b , 2015 ).…”

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Evidence for similar early but not late representation of possible and impossible objects

et al. 2015

Self Cite

View full text Add to dashboard Cite

The perceptual processes that mediate the ability to efficiently represent object 3D structure are still not fully understood. The current study was aimed to shed light on these processes by utilizing spatially possible and impossible objects that could not be created in real 3D space. Despite being perceived as exceptionally unusual, impossible objects still possess fundamental Gestalt attributes and valid local depth cues that may support their initial successful representation. Based on this notion and on recent findings from our lab, we hypothesized that the initial representation of impossible objects would involve common mechanisms to those mediating typical object perception while the perceived differences between possible and impossible objects would emerge later along the processing hierarchy. In Experiment 1, participants preformed same/different classifications of two markers superimposed on a display containing two objects (possible or impossible). Faster reaction times were observed for displays in which the markers were superimposed on the same object (“object-based benefit”). Importantly, this benefit was similar for possible and impossible objects, suggesting that the representations of the two object categories rely on similar perceptual organization processes. Yet, responses for impossible objects were slower compared to possible objects. Experiment 2 was designed to examine the origin of this effect. Participants classified the location of two markers while exposure duration was manipulated. A similar pattern of performance was found for possible and impossible objects for the short exposure duration, with differences in accuracy between these two types of objects emerging only for longer exposure durations. Overall, these findings provide evidence that the representation of object structure relies on a multi-level process and that object impossibility selectively impairs the rendering of fine-detailed description of object structure.

show abstract

Section: Introductionsupporting

confidence: 60%

Section: Discussionmentioning

confidence: 83%

See 1 more Smart Citation

Evidence for similar early but not late representation of possible and impossible objects

et al. 2015

Self Cite

View full text Add to dashboard Cite

show abstract

“…Shape is the most fundamental perceived property of objects, and, accordingly, shape processing is crucial for successful visual object recognition ( Palmer, 1999 ). Deriving information about the shapes of objects in the input has long been considered to be under the purview of the ventral visual pathway ( Goodale and Milner, 1992 ; Ungerleider and Mishkin, 1982 ) and many functional imaging studies have provided evidence to support this claim (e.g., Freud et al, 2013 ; Grill-Spector et al, 1998 ; Kourtzi and Kanwisher, 2000 ; Lerner et al, 2001 ; Malach et al, 1995 ). Specifically, these investigations have uncovered a gradient of shape sensitivity in the ventral pathway, with posterior regions in the early to mid-visual cortex (i.e., V1-hV4) being less responsive to the shape of the object than more anterior regions, such as the Lateral Occipital Cortex (LOC) and the Fusiform Gyrus (FG).…”

Section: Introductionmentioning

confidence: 99%

The large-scale organization of shape processing in the ventral and dorsal pathways

Freud

Culham

Plaut

et al. 2017

eLife

Self Cite

View full text Add to dashboard Cite

Although shape perception is considered a function of the ventral visual pathway, evidence suggests that the dorsal pathway also derives shape-based representations. In two psychophysics and neuroimaging experiments, we characterized the response properties, topographical organization and perceptual relevance of these representations. In both pathways, shape sensitivity increased from early visual cortex to extrastriate cortex but then decreased in anterior regions. Moreover, the lateral aspect of the ventral pathway and posterior regions of the dorsal pathway were sensitive to the availability of fundamental shape properties, even for unrecognizable images. This apparent representational similarity between the posterior-dorsal and lateral-ventral regions was corroborated by a multivariate analysis. Finally, as with ventral pathway, the activation profile of posterior dorsal regions was correlated with recognition performance, suggesting a possible contribution to perception. These findings challenge a strict functional dichotomy between the pathways and suggest a more distributed model of shape processing.

show abstract

“…Most of the studies using the impossible/possible object-decision test investigated object representation in long-term memory (e.g. Schacter et al, 1990 ; Schacter et al, 1991 ; Soldan et al, 2009 ), and only a few of them have considered the perceptual aspects underlying this discrimination ( Carrasco & Seamon, 1996 ; Donnelly et al, 1999 ; Freud, Avidan, & Ganel, 2013 ; Freud, Ganel, & Avidan, 2013 ; Seamon & Carrasco, 1999 ; Williams & Tarr, 1997 ). Impossible objects have valid object properties (e.g.…”

Section: Discussionmentioning

confidence: 99%

Drawing Skill is Related to the Efficiency of Encoding Object Structure

Perdreau

Cavanagh

2014

i-Perception

View full text Add to dashboard Cite

Accurate drawing calls on many skills beyond simple motor coordination. A good internal representation of the target object's structure is necessary to capture its proportion and shape in the drawing. Here, we assess two aspects of the perception of object structure and relate them to participants' drawing accuracy. First, we assessed drawing accuracy by computing the geometrical dissimilarity of their drawing to the target object. We then used two tasks to evaluate the efficiency of encoding object structure. First, to examine the rate of temporal encoding, we varied presentation duration of a possible versus impossible test object in the fovea using two different test sizes (8° and 28°). More skilled participants were faster at encoding an object's structure, but this difference was not affected by image size. A control experiment showed that participants skilled in drawing did not have a general advantage that might have explained their faster processing for object structure. Second, to measure the critical image size for accurate classification in the periphery, we varied image size with possible versus impossible object tests centered at two different eccentricities (3° and 8°). More skilled participants were able to categorise object structure at smaller sizes, and this advantage did not change with eccentricity. A control experiment showed that the result could not be attributed to differences in visual acuity, leaving attentional resolution as a possible explanation. Overall, we conclude that drawing accuracy is related to faster encoding of object structure and better access to crowded details.

show abstract

Representation of possible and impossible objects in the human visual cortex: Evidence from fMRI adaptation

Cited by 20 publications

References 43 publications

Evidence for similar early but not late representation of possible and impossible objects

Evidence for similar early but not late representation of possible and impossible objects

The large-scale organization of shape processing in the ventral and dorsal pathways

Drawing Skill is Related to the Efficiency of Encoding Object Structure

Contact Info

Product

Resources

About