Material recognition and the role of assumed viewing distance

Displays were presented consisting of a perspective projection of a regular square grid, made up of vertical and horizontal equally spaced white lines, that was slanted in depth. The surface was viewed monocularly, through a circular aperture. A range of slants was shown (0°, 10°, 20°, 30°, 40°, 50°, or 60°) and the observers' task was to match the slant by means of a mouse-driven probe. The viewing distance (50, 75, or 100 cm) as well as the focal distance (25, 50, 75, 100, or 125 cm) were varied. We expected the estimation error to be smallest when the viewing distance and the focal distance coincided. This was not the case. Instead, subjects seemed to use the perspective deformation of the texture elements in the stimulus display to make a slant estimation, regardless of the specific combination of viewing distance and focal distance.

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Effect of Viewing Distance On Object Responses In Macaque Areas 45B, F5a And F5p

10.21203/rs.3.rs-969958/v1 ◽

2021 ◽

Author(s):

Irene Caprara ◽

Peter Janssen

Keyword(s):

Visual Representation ◽

Motor Command ◽

Peripersonal Space ◽

Visual Object ◽

Viewing Distance ◽

Visually Guided ◽

Grip Aperture ◽

Object Processing ◽

The Brain

Abstract To perform tasks like grasping, the brain has to process visual object information so that the grip aperture can be adjusted before touching the object. Previous studies have demonstrated that the posterior subsector of the Anterior Intraparietal area (pAIP) is connected to area 45B, and its anterior counterpart (aAIP) to F5a. However, the role of area 45B and F5a in visually-guided grasping is poorly understood. Here, we investigated the role of area 45B, F5a and F5p in object processing during visually-guided grasping in two monkeys. If the presentation of an object activates a motor command related to the preshaping of the hand, as in F5p, such neurons should prefer objects presented within reachable distance. Conversely, neurons encoding a purely visual representation of an object – possibly in area 45B and F5a – should be less affected by viewing distance. Contrary to our expectations, we found that most neurons in area 45B were object- and viewing distance-selective (mostly Near-preferring). Area F5a showed much weaker object selectivity compared to 45B, with a similar preference for objects presented at the Near position. Finally, F5p neurons were less object selective and frequently Far-preferring. In sum, area 45B – but not F5p– prefers objects presented in peripersonal space.

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The joint role of geometry and illumination on material recognition

Journal of Vision ◽

10.1167/jov.21.2.2 ◽

2021 ◽

Vol 21 (2) ◽

pp. 2

Author(s):

Manuel Lagunas ◽

Ana Serrano ◽

Diego Gutierrez ◽

Belen Masia

Keyword(s):

Material Recognition

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The Role of Viewing Distance and Feedback on Affordance Judgments in Augmented Reality

2020 IEEE Conference on Virtual Reality and 3D User Interfaces (VR) ◽

10.1109/vr46266.2020.00112 ◽

2020 ◽

Author(s):

Holly C. Gagnon ◽

Dun Na ◽

Keith Heiner ◽

Jeanine Stefanucci ◽

Sarah Creem-Regehr ◽

...

Keyword(s):

Augmented Reality ◽

Viewing Distance

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The role of viewing distance and viewing angle on referees’ decision-making performance during the FIFA World Cup 2014

Journal of Sports Sciences ◽

10.1080/02640414.2019.1570898 ◽

2019 ◽

Vol 37 (13) ◽

pp. 1481-1489 ◽

Cited By ~ 4

Author(s):

Ernst-Joachim Hossner ◽

Urs Schnyder ◽

Jürg Schmid ◽

Ralf Kredel

Keyword(s):

Decision Making ◽

Viewing Distance ◽

Viewing Angle ◽

World Cup ◽

Fifa World Cup

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Spatial constant equi-affine speed and motion perception

Journal of Neurophysiology ◽

10.1152/jn.01071.2012 ◽

2014 ◽

Vol 111 (2) ◽

pp. 336-349 ◽

Cited By ~ 7

Author(s):

Uri Maoz ◽

Tamar Flash

Keyword(s):

Motion Perception ◽

Power Law ◽

Critical Role ◽

Three Dimensional ◽

Affine Geometry ◽

Human Hand ◽

Viewing Distance ◽

Spatial Motion ◽

Elliptical Motion

The two-thirds power law, postulating an inverse local relation between the velocity and cubed root of curvature of planar trajectories, is a long-established simplifying principle of human hand movements. In perception, the motion of a dot along a planar elliptical path appears most uniform for speed profiles closer to those predicted by the power law than to constant Euclidean speed, a kinetic-visual illusion. Mathematically, complying with this law is equivalent to moving at constant planar equi-affine speed, while unconstrained three-dimensional drawing movements generally follow constant spatial equi-affine speed. Here we test the generalization of this illusion to visual perception of spatial motion for a dot moving along five differently shaped paths, using stereoscopic projection. The movements appeared most uniform for speed profiles closer to constant spatial equi-affine speed than to constant Euclidean speed, with path torsion (i.e., local deviation from planarity) directly affecting the speed profiles perceived as most uniform, as predicted for constant spatial equi-affine speed. This demonstrates the dominance of equi-affine geometry in spatial motion perception. However, constant equi-affine speed did not fully account for the variability among the speed profiles selected as most uniform for different shapes. Moreover, in a followup experiment, we found that viewing distance affected the speed profile reported as most uniform for the extensively studied planar elliptical motion paths. These findings provide evidence for the critical role of equi-affine geometry in spatial motion perception and contribute to the mounting evidence for the role of non-Euclidean geometries in motion perception and production.

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Patriotic Rewards, New Freedoms

First Americans ◽

10.12987/yale/9780300224337.003.0006 ◽

2018 ◽

Author(s):

Thomas Grillot

Keyword(s):

Social Capital ◽

Native American ◽

World War I ◽

Indian Policy ◽

Testing Time ◽

World War ◽

Material Recognition ◽

The Core ◽

New Strategy

This chapter applies the insights of the previous chapters to the examination of the role of patriotism and veterans in shaping Indian policy from the 1920s. It shows how, for veterans and non-veterans alike, Native American participation in World War I was an opportunity to ask the state and the general public for moral and material recognition. Although they derived few tangible benefits from this mobilization, the ability of veterans to claim the attention of non-Indians allowed them to accumulate a level of political savvy and social capital rarely encountered in their communities. The 1920s were a testing time for Native patriots and a testing ground for a new strategy. In the process, they asked troubling questions: Could Indians be freed from BIA supervision? And with what consequences? Patriotism suggested new answers to what was, after all, the core of the “Indian problem.”

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Effect of viewing distance on object responses in macaque areas 45B, F5a and F5p

10.1101/2020.05.04.070862 ◽

2020 ◽

Author(s):

I Caprara ◽

P Janssen

Keyword(s):

Object Representation ◽

Neuronal Response ◽

Motor Command ◽

Peripersonal Space ◽

Neural Representation ◽

Visual Object ◽

Viewing Distance ◽

Visually Guided ◽

Visual Responses

AbstractTo perform real-world tasks like grasping, the primate brain has to process visual object information so that the grip aperture can be adjusted before contact with the object is made. Previous studies have demonstrated that the posterior subsector of the Anterior Intraparietal area (pAIP) is connected to frontal area 45B, and the anterior subsector of AIP (aAIP) to F5a (Premereur et al., 2015). However, the role of area 45B and F5a in visually-guided object grasping is poorly understood. Here, we investigated the role of area 45B, F5a and F5p in visually-guided grasping. If a neuronal response to an object during passive fixation represents the activation of a motor command related to the preshaping of the hand, such neurons should prefer objects presented within reachable distance. Conversely, neurons encoding a pure visual representation of an object should be less affected by viewing distance. Contrary to our expectations, we found that the majority of neurons in area 45B were object- and viewing distance selective, with a clear preference for the near viewing distance. Area F5a showed much weaker object selectivity compared to 45B, with a similar preference for objects presented at the Near position emerging mainly in the late epoch. Finally, F5p neurons were less object selective and frequently preferred objects presented at the Far position. Therefore, contrary to our expectations, neurons in area 45B – but not F5p neurons – prefer objects presented in peripersonal space.Significance statementThe current experiment provides the first evidence on the neural representation of distance in frontal areas that are active during visually-guided grasping. Area 45B and F5a neurons were object- and distance-selective, and preferred the near viewing distance even for objects with identical retinal size. In area F5p we observed strong visual responses with an unexpected preference for the Far viewing distance, suggesting that the motor-related object representation was still active during the presentation of objects outside reaching distance.

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