Object Recognition Processes Can and Do Operate Before Figure–Ground Organization

1994 ◽  
Vol 3 (4) ◽  
pp. 105-111 ◽  
Author(s):  
Mary A. Peterson
Keyword(s):  
Object Recognition ◽  
Ground Organization

Must Figure-Ground Organization Precede Object Recognition? An Assumption in Peril

1994 ◽  
Vol 5 (5) ◽  
pp. 253-259 ◽  
Author(s):  
Mary A. Peterson ◽  
Bradley S. Gibson
Keyword(s):  
Object Recognition ◽  
Visual Perception ◽  
Shape Recognition ◽  
Ground Segmentation ◽  
Ground Organization

The assumption that figure-ground segmentation must precede object or shape recognition has been central to theories of visual perception We showed that assumption to be incorrect in an experiment in which observers reported the first perceived figure-ground organization of briefly exposed stimuli depicting two regions sharing a figure-ground border We manipulated the symmetry of the two regions and their orientation-dependent denotivity (roughly, their meaningfulness), and measured how each of these variables influenced figure-ground reports when the stimuli were exposed for 14, 28, 57, 86, or 100 ms, and followed immediately by a mask Influences on figure-ground organization from both symmetry and orientation-dependent object recognition processes were found, both were observed first in the 28-ms condition Object recognition inputs did not dominate symmetry inputs We suggest that object recognition processes may operate simultaneously on both sides of edges detected before figure-ground relationships are determined

scholarly journals Figure-ground organization in the visual cortex: does meaning matter?

2018 ◽  
Vol 119 (1) ◽  
pp. 160-176 ◽  
Author(s):  
Hee-kyoung Ko ◽  
Rüdiger von der Heydt
Keyword(s):  
Visual Cortex ◽  
Object Recognition ◽  
Temporal Lobe ◽  
Stimulus Onset ◽  
Top Down ◽  
General Rules ◽  
The Face ◽  
Shape Selective ◽  
Shape Categorization ◽  
Ground Organization

Figure-ground organization in the visual cortex is generally assumed to be based partly on general rules and partly on specific influences of object recognition in higher centers as found in the temporal lobe. To see if shape familiarity influences figure-ground organization, we tested border ownership-selective neurons in monkey V1/V2 with silhouettes of human and monkey face profiles and “nonsense” silhouettes constructed by mirror-reversing the front part of the profile. We found no superiority of face silhouettes compared with nonsense shapes in eliciting border-ownership signals overall. However, in some neurons, border-ownership signals differed strongly between the two categories consistently across many different profile shapes. Surprisingly, this category selectivity appeared as early as 70 ms after stimulus onset, which is earlier than the typical latency of shape-selective responses but compatible with the earliest face-selective responses in the inferior temporal lobe. Although our results provide no evidence for a delayed top-down influence from object recognition centers, they indicate sophisticated shape categorization mechanisms that are much faster than generally assumed. NEW & NOTEWORTHY A long-standing question is whether low-level sensory representations in cortex are influenced by cognitive “top-down” signals. We studied figure-ground organization in the visual cortex by comparing border-ownership signals for face profiles and matched nonsense shapes. We found no sign of “face superiority” in the population border-ownership signal. However, some neurons consistently differentiated between the face and nonsense categories early on, indicating the presence of shape classification mechanisms that are much faster than previously assumed.

Neuropsychological studies of object recognition

1982 ◽  
Vol 298 (1089) ◽  
pp. 15-33 ◽  
Keyword(s):  
Object Recognition ◽  
Visual Perception ◽  
Visual Impairment ◽  
Right Hemisphere ◽  
Visual Stimuli ◽  
Perceptual Categorization ◽  
Tentative Model ◽  
The Right ◽  
Ground Organization

It is well established that disorders of visual perception are associated with lesions in the right hemisphere. Performances on tasks as disparate as the identification of objects from unusual views or objects drawn so as to overlap, of fragmented letters, of familiar faces, and of anomalous features in drawings, have been shown to be impaired in patients with focal right posterior lesions. A series of investigations are reviewed, directed towards analysing the basis of these deficits. Explanations in terms of primary visual impairment can be rejected, as can an account in terms of faulty figure-ground organization. It is argued that a wide variety of such perceptual deficits - all of which are concerned with meaningful visual stimuli - can be encompassed by the notion of faulty perceptual categorization at an early post-sensory stage of object recognition. Moreover, there is evidence suggesting that some of these various perceptual deficits can be mutually dissociated. The concept of perceptual categorization is discussed in the wider context of a tentative model of object recognition.

Use It and Still Lose It?

GeroPsych ◽  
2010 ◽  
Vol 23 (3) ◽  
pp. 169-175 ◽  
Author(s):  
Adrian Schwaninger ◽  
Diana Hardmeier ◽  
Judith Riegelnig ◽  
Mike Martin
Keyword(s):  
Object Recognition ◽  
Cognitive Development ◽  
Recognition Test ◽  
Cognitive Aging ◽  
Recognition Task ◽  
Airport Security ◽  
Visual Object ◽  
Long Term Effects ◽  
Object Recognition Test ◽  
X Ray

In recent years, research on cognitive aging increasingly has focused on the cognitive development across middle adulthood. However, little is still known about the long-term effects of intensive job-specific training of fluid intellectual abilities. In this study we examined the effects of age- and job-specific practice of cognitive abilities on detection performance in airport security x-ray screening. In Experiment 1 (N = 308; 24–65 years), we examined performance in the X-ray Object Recognition Test (ORT), a speeded visual object recognition task in which participants have to find dangerous items in x-ray images of passenger bags; and in Experiment 2 (N = 155; 20–61 years) in an on-the-job object recognition test frequently used in baggage screening. Results from both experiments show high performance in older adults and significant negative age correlations that cannot be overcome by more years of job-specific experience. We discuss the implications of our findings for theories of lifespan cognitive development and training concepts.

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