Object representations in visual cortex are scaled to account for viewing distance during visual search

Visual search is a ubiquitous visual behavior, and efficient search is essential for survival. Different cognitive models have explained the speed and accuracy of search based either on the dynamics of attention or on similarity of item representations. Here, we examined the extent to which performance on a visual search task can be predicted from the stable representational architecture of the visual system, independent of attentional dynamics. Participants performed a visual search task with 28 conditions reflecting different pairs of categories (e.g., searching for a face among cars, body among hammers, etc.). The time it took participants to find the target item varied as a function of category combination. In a separate group of participants, we measured the neural responses to these object categories when items were presented in isolation. Using representational similarity analysis, we then examined whether the similarity of neural responses across different subdivisions of the visual system had the requisite structure needed to predict visual search performance. Overall, we found strong brain/behavior correlations across most of the higher-level visual system, including both the ventral and dorsal pathways when considering both macroscale sectors as well as smaller mesoscale regions. These results suggest that visual search for real-world object categories is well predicted by the stable, task-independent architecture of the visual system. NEW & NOTEWORTHY Here, we ask which neural regions have neural response patterns that correlate with behavioral performance in a visual processing task. We found that the representational structure across all of high-level visual cortex has the requisite structure to predict behavior. Furthermore, when directly comparing different neural regions, we found that they all had highly similar category-level representational structures. These results point to a ubiquitous and uniform representational structure in high-level visual cortex underlying visual object processing.

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Magnetoencephalography adaptation reveals depth-cue-invariant object representations in the visual cortex

Journal of Vision ◽

10.1167/18.12.6 ◽

2018 ◽

Vol 18 (12) ◽

pp. 6

Author(s):

Hassan Akhavein ◽

Armita Dehmoobadsharifabadi ◽

Reza Farivar

Keyword(s):

Visual Cortex ◽

Object Representations ◽

Depth Cue

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Transformation from independent to integrative coding of multi-object arrangements in human visual cortex

10.1101/117432 ◽

2017 ◽

Cited By ~ 1

Author(s):

Daniel Kaiser ◽

Marius V. Peelen

Keyword(s):

Visual Cortex ◽

Visual System ◽

Activity Patterns ◽

Spatial Arrangement ◽

Living Room ◽

Natural Scenes ◽

Response Patterns ◽

Object Representations ◽

Individual Object ◽

Object Coding

AbstractTo optimize processing, the human visual system utilizes regularities present in naturalistic visual input. One of these regularities is the relative position of objects in a scene (e.g., a sofa in front of a television), with behavioral research showing that regularly positioned objects are easier to perceive and to remember. Here we use fMRI to test how positional regularities are encoded in the visual system. Participants viewed pairs of objects that formed minimalistic two-object scenes (e.g., a “living room” consisting of a sofa and television) presented in their regularly experienced spatial arrangement or in an irregular arrangement (with interchanged positions). Additionally, single objects were presented centrally and in isolation. Multi-voxel activity patterns evoked by the object pairs were modeled as the average of the response patterns evoked by the two single objects forming the pair. In two experiments, this approximation in object-selective cortex was significantly less accurate for the regularly than the irregularly positioned pairs, indicating integration of individual object representations. More detailed analysis revealed a transition from independent to integrative coding along the posterior-anterior axis of the visual cortex, with the independent component (but not the integrative component) being almost perfectly predicted by object selectivity across the visual hierarchy. These results reveal a transitional stage between individual object and multi-object coding in visual cortex, providing a possible neural correlate of efficient processing of regularly positioned objects in natural scenes.

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Contextual location information relevant to visual search in natural scenes is encoded in extrastriate visual cortex and the anterior intraparietal sulcus

Journal of Vision ◽

10.1167/11.11.819 ◽

2011 ◽

Vol 11 (11) ◽

pp. 819-819

Author(s):

T. Preston ◽

F. Guo ◽

B. Giesbrecht ◽

M. Eckstein

Keyword(s):

Visual Cortex ◽

Visual Search ◽

Location Information ◽

Natural Scenes ◽

Intraparietal Sulcus ◽

Extrastriate Visual Cortex ◽

Anterior Intraparietal Sulcus

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Ultrafast Object Detection in Naturalistic Vision Relies on Ultrafast Distractor Suppression

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_01437 ◽

2019 ◽

Vol 31 (10) ◽

pp. 1563-1572 ◽

Cited By ~ 1

Author(s):

Clayton Hickey ◽

Daniele Pollicino ◽

Giacomo Bertazzoli ◽

Ludwig Barbaro

Keyword(s):

Visual Cortex ◽

Spatial Attention ◽

Brain Activity ◽

Natural Scenes ◽

Search Efficiency ◽

Object Representations ◽

Target Presence ◽

Object Categories ◽

Frontal Brain ◽

Scene Information

People are quicker to detect examples of real-world object categories in natural scenes than is predicted by classic attention theories. One explanation for this puzzle suggests that experience renders the visual system sensitive to midlevel features diagnosing target presence. These are detected without the need for spatial attention, much as occurs for targets defined by low-level features like color or orientation. The alternative is that naturalistic search relies on spatial attention but is highly efficient because global scene information can be used to quickly reject nontarget objects and locations. Here, we use ERPs to differentiate between these possibilities. Results show that hallmark evidence of ultrafast target detection in frontal brain activity is preceded by an index of spatially specific distractor suppression in visual cortex. Naturalistic search for heterogenous targets therefore appears to rely on spatial operations that act on neural object representations, as predicted by classic attention theory. People appear able to rapidly reject nontarget objects and locations, consistent with the idea that global scene information is used to constrain naturalistic search and increase search efficiency.

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General Transformations of Object Representations in Human Visual Cortex

Journal of Neuroscience ◽

10.1523/jneurosci.2800-17.2018 ◽

2018 ◽

Vol 38 (40) ◽

pp. 8526-8537 ◽

Cited By ~ 4

Author(s):

Emily J. Ward ◽

Leyla Isik ◽

Marvin M. Chun

Keyword(s):

Visual Cortex ◽

Object Representations ◽

Human Visual Cortex

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Curved Versus Flat Monitors: Interactive Effects of Display Curvature Radius and Display Size on Visual Search Performance and Visual Fatigue

Human Factors The Journal of the Human Factors and Ergonomics Society ◽

10.1177/0018720820922717 ◽

2020 ◽

pp. 001872082092271

Author(s):

Gyouhyung Kyung ◽

Sungryul Park

Keyword(s):

Visual Search ◽

Display Size ◽

Interactive Effects ◽

Curvature Radius ◽

Viewing Distance ◽

Search Performance ◽

Visual Fatigue ◽

Visual Display Terminal ◽

Search Tasks ◽

Curved Displays

Objective The aim of this study is to examine the interactive effects of display curvature radius and display size on visual search accuracy, visual search speed, and visual fatigue. Background Although the advantages of curved displays have been reported, little is known about the interactive effects of display curvature radius and size. Method Twenty-seven individuals performed visual search tasks at a viewing distance of 50 cm using eight configurations involving four display curvature radii (400R, 600R, 1200R, and flat) and two display sizes (33″ and 50″). To simulate curved screens, five flat display panels were horizontally arranged with their centers concentrically repositioned following each display curvature radius. Results For accuracy, speed, and fatigue, 33″–600R and 50″–600R provided the best or comparable-to-best results, whereas 50″–flat provided the worst results. For accuracy and fatigue, 33″–flat was the second worst. The changes in the horizontal field of view and viewing angle due to display curvature as well as the association between effective display curvature radii and empirical horopter (loci of perceived equidistance) can explain these results. Conclusion The interactive effects of display curvature radius and size were evident for visual search performance and fatigue. Beneficial effects of curved displays were maintained across 33″ and 50″, whereas increasing flat display size from 33″ to 50″ was detrimental. Application For visual search tasks at a viewing distance of 50 cm, 33″–600R and 50″ 600R displays are recommended, as opposed to 33″ and 50″ flat displays. Wide flat displays must be carefully considered for visual display terminal tasks.

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