Crowding for faces is determined by visual (not holistic) similarity: Evidence from judgements of eye position

Kalpadakis-Smith, Alexandra V.; Goffaux, Valérie; Greenwood, John A.

doi:10.1038/s41598-018-30900-0

Cited by 24 publications

(29 citation statements)

References 76 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At first glance, independent crowding effects for distinct visual features bears some similarity to multi-level theories of crowding (4,51). However, these theories are based on an apparent uniqueness in the crowding of faces (52), an effect that disappears once task difficulty is equated for upright and inverted faces (53). Although we do observe some differences in the crowding for motion and colour (e.g.…”

Section: Discussionsupporting

confidence: 67%

Dissociable effects of visual crowding on the perception of colour and motion

Greenwood

Parsons

2019

Preprint

Self Cite

View full text Add to dashboard Cite

Our ability to recognise objects in peripheral vision is fundamentally limited by crowding, the deleterious effect of clutter that disrupts the recognition of features ranging from orientation and colour to motion and depth. Prior research is equivocal on whether this reflects a singular process that disrupts all features simultaneously or multiple processes that affect each independently. We examined crowding for motion and colour, two features that allow a strong test of feature independence. 'Cowhide' stimuli were presented 15 degrees in peripheral vision, either in isolation or surrounded by flankers to give crowding. Observers reported either the target hue (blue/purple) or its direction (clockwise/counterclockwise from upwards). We first established that both features show systematic crowded errors (predominantly biased towards the flanker identities) and selectivity for target-flanker similarity (with reduced crowding for dissimilar target/flanker elements). The multiplicity of crowding was then tested with observers identifying both features: a singular object-selective mechanism predicts that when crowding is weak for one feature and strong for the other that crowding should be all-or-none for both. In contrast, when crowding was weak for colour and strong for motion, errors were reduced for colour but remained for motion, and vice versa with weak motion and strong colour crowding. This double dissociation follows the predictions of independent crowding processes, suggesting that crowding can disrupt vision in a feature-specific manner. The ability to recognise one aspect of a cluttered scene, like colour, thus offers no guarantees for the correct recognition of other aspects, like motion. Significance statementThe fundamental limitation on our peripheral vision is crowding, the disruptive effect of image clutter on object recognition. Crowding is widely assumed to be a singular process, affecting all of the features (e.g. orientation, motion, and colour) within an object simultaneously. In contrast, we find a double dissociation for these disruptions: observers can make errors in judging the colour of a crowded object whilst correctly judging its movement direction, and vice versa. This dissociation is well described by a population-coding model that independently pools the motion and colour of target and flanker elements. We suggest that crowding may be a generic set of processes distributed throughout the visual system that independently simplify the representation of our visual field.

show abstract

Section: Discussionsupporting

confidence: 67%

Dissociable effects of visual crowding on the perception of colour and motion

Greenwood

Parsons

2019

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…Indeed, while the upright face is a top-heavy stimulus, i.e. it contains most of its contrast in the upper part [56][57][58], the inverted face is bottom-heavy. Because early visual regions are retinotopic, they activate different populations of neurons for upright and inverted faces, populations that may differ in their orientation selectivity profile.…”

Section: Discussionmentioning

confidence: 99%

Contrast versus identity encoding in the face image follow distinct orientation selectivity profiles

Jacobs¹,

Petras

Moors

et al. 2020

PLoS ONE

View full text Add to dashboard Cite

Orientation selectivity is a fundamental property of primary visual encoding. High-level processing stages also show some form of orientation dependence, with face identification preferentially relying on horizontally-oriented information. How high-level orientation tuning emerges from primary orientation biases is unclear. In the same group of participants, we derived the orientation selectivity profile at primary and high-level visual processing stages using a contrast detection and an identity matching task. To capture the orientation selectivity profile, we calculated the difference in performance between all tested orientations (0, 45, 90, and 135˚) for each task and for upright and inverted faces, separately. Primary orientation selectivity was characterized by higher sensitivity to oblique as compared to cardinal orientations. The orientation profile of face identification showed superior horizontal sensitivity to face identity. In each task, performance with upright and inverted faces projected onto qualitatively similar a priori models of orientation selectivity. Yet the fact that the orientation selectivity profiles of contrast detection in upright and inverted faces correlated significantly while such correlation was absent for identification indicates a progressive dissociation of orientation selectivity profiles from primary to high-level stages of orientation encoding. Bayesian analyses further indicate a lack of correlation between the orientation selectivity profiles in the contrast detection and face identification tasks, for upright and inverted faces. From these findings, we conclude that orientation selectivity shows distinct profiles at primary and high-level stages of face processing and that a transformation must occur from general cardinal attenuation when processing basic properties of the face image to horizontal tuning when encoding more complex properties such as identity.

show abstract

“…The baseline difficulty for the three types of stimuli was not matched in this experiment. This can be an issue because task difficulty modulates crowding 64 . The gist advantage might change if the task difficulty for each stimulus type were matched.…”

Section: Discussionmentioning

confidence: 99%

The extraction of natural scene gist in visual crowding

Gong

Xuan

Smart

et al. 2018

Sci Rep

View full text Add to dashboard Cite

The gist of natural scenes can be extracted very rapidly and even without focal attention. However, it is unclear whether and to what extent the gist of natural scenes can break through the bottleneck of crowding, a phenomenon in which object recognition will be immensely impaired. In the first two experiments, a target scene, either presented alone or surrounded by four flankers, was categorized at basic (Experiment 1) or global levels (Experiment 2). It was showed that the elimination of high-level semantic information of flankers greatly alleviated the crowding effect, demonstrating that high-level information played an important role in crowding of scene gist. More importantly, participants were able to categorize the scenes in crowding at rather high accuracies, suggesting that the extraction of scene gist might be a prioritized process. To test this hypothesis, in Experiment 3 we compared the crowding effect of three types of stimuli, namely, scenes, facial expressions and letter “E”s. The results showed that scenes could be better categorized than the other two types of stimuli in the crowding condition. This scene gist advantage thus supported our hypothesis. Together, the present studies suggest that scene gist is highly recognizable in crowding, probably due to its prioritization in visual processing.

show abstract

Crowding for faces is determined by visual (not holistic) similarity: Evidence from judgements of eye position

Cited by 24 publications

References 76 publications

Dissociable effects of visual crowding on the perception of colour and motion

Dissociable effects of visual crowding on the perception of colour and motion

Contrast versus identity encoding in the face image follow distinct orientation selectivity profiles

The extraction of natural scene gist in visual crowding

Contact Info

Product

Resources

About