Toward View-Invariant Representations of Object Structure Learned Using Object Constancy Cues in Natural Movies

2005 ◽  
Author(s):  
J.B. Colombe
Keyword(s):  
Object Constancy ◽  
Object Structure ◽  
Invariant Representations

Measurement and Reduction of Radiation Damage in Frozen Hydrated Crystalline Specimens

1978 ◽  
Vol 36 (3) ◽  
pp. 70-77 ◽  
Author(s):  
R.M. Glaeser ◽  
S.B. Hayward
Keyword(s):  
Diffraction Pattern ◽  
Structural Information ◽  
Structural Disorder ◽  
Structural Features ◽  
Biological Macromolecules ◽  
Diffraction Intensity ◽  
Object Structure ◽  
Specimen Material ◽  
Unit Cells ◽  
Identical Unit

Highly ordered or crystalline biological macromolecules become severely damaged and structurally disordered after a brief electron exposure. Evidence that damage and structural disorder are occurring is clearly given by the fading and eventual disappearance of the specimen's electron diffraction pattern. The fading and disappearance of sharp diffraction spots implies a corresponding disappearance of periodic structural features in the specimen. By the same token, there is a oneto- one correspondence between the disappearance of the crystalline diffraction pattern and the disappearance of reproducible structural information that can be observed in the images of identical unit cells of the object structure. The electron exposures that result in a significant decrease in the diffraction intensity will depend somewhat upon the resolution (Bragg spacing) involved, and can vary considerably with the chemical makeup and composition of the specimen material.

Functions of Same-Tracking

2017 ◽  
Author(s):  
Ruth Garrett Millikan
Keyword(s):  
Relative Location ◽  
Perceptual Constancy ◽  
Object Constancy ◽  
The Difference

There are non-uniceptual same-tracking mechanisms, mechanisms that same-track not in order to implement storage of information about their targets, but merely as an aid to the identification of further things. Examples are the various mechanisms of perceptual constancy, self-relative location trackers, object-constancy mechanisms, and same-trackers for real categories. There are also several kinds of unicepts, hence, of unitrackers, procedural, substantive, attributive. What begins as a non-uniceptual same-tracker might or might not be redeployed to serve also as a procedural unitracker, or a procedural unitracker might be redeployed to serve also as a substance unitracker or an attribute unitracker. This is possible because the difference between affordances, substances, and attributes is not a basic ontological distinction but is relative to cognitive use.

Routes to Object Constancy: Implications from Neurological Impairments of Object Constancy

1984 ◽  
Vol 36 (3) ◽  
pp. 385-415 ◽  
Author(s):  
Glyn W. Humphreys ◽  
M. Jane Riddoch
Keyword(s):  
Distinctive Feature ◽  
Principal Axis ◽  
Target Object ◽  
Matching Task ◽  
Size Discrimination ◽  
Form Discrimination ◽  
Object Constancy ◽  
Distinctive Features ◽  
Global Properties ◽  
Feature Information

Previous studies have established the existence of neurological impairments of object constancy: the ability to recognize that an object has the same structure across changes in its retinal projection. Five case studies of brain-damaged patients with deficits in achieving object constancy are reported. To test object constancy, patients discriminated two photographs of a target object, taken from different views, from a photograph of a visually similar distractor object. Four patients showed impaired matching only when the principal axis of the target object in one photograph was foreshortened. The fifth patient showed impaired matching only when the saliency of the target object's primary distinctive feature was reduced. This double dissociation suggests that normally there may be two independent means of achieving object constancy: one by processing an object's local distinctive features, the other by describing the object's structure relative to the frame of its principal axis. Neurological damage can selectively impair either process. Further, this impairment can be independent of deficits in processing visual form, since two patients with a selective deficit in the foreshortened matching task showed relatively normal form discrimination. The patient dependent on local distinctive feature information showed a deficit in size discrimination. It is suggested that this patient fails to utilize global properties of form. This failure may underlie both his impairment in achieving object constancy and in processing certain dimensions of form.

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