Are first-order disparity gradients spatial primitives of the orientation of lines on the ground plane?
Psychol. neurosci. (Impr.)
; 7(3): 285-299, July-Dec. 2014. ilus, tab
Artigo
em Inglês
| LILACS
| ID: lil-741662
Biblioteca responsável:
BR85.1
ABSTRACT
The present study investigated the mechanisms involved in processing orientation on the frontal and ground planes. The stimuli comprised two yellow circles conceived as the endpoints of a segment and depicted on a black background. In Experiment 1, the observers performed two tasks on both planes (frontal and ground). In Task 1 they were asked to indicate the absolute location of the two endpoints, presented one at a time (successive task). In Task 2 they had to locate the relative position of the endpoints presented simultaneously (simultaneous task). Relative and absolute errors were analyzed according to a cyclopean coordinate system derived from the geometry of the visual scene. These two kinds of errors were studied within the framework of the hypothesis that each kind of task would minimize the error related to its codification. The results showed greater absolute errors in the simultaneous task than in the successive task and greater relative errors in which the successive task seemingly activated a more accurate way of codification of the orientation. In Experiment 2 we controlled the availability of visual depth cues by changing the presentation time (50 and 3000 ms) and viewing conditions (monocular and binocular) in the simultaneous task. The results showed that the precision of orientation judgments was poorer on the ground plane than on the frontal plane, except when the observers used binocular vision. These results suggest that the orientation of a segment, at least on the ground plane, can be conceptualized as a gradient of disparities.
Texto completo:
Disponível
Coleções:
Bases de dados internacionais
Contexto em Saúde:
Agenda de Saúde Sustentável para as Américas
Problema de saúde:
Objetivo 11 Desigualdades e iniquidades na saúde
Base de dados:
LILACS
Assunto principal:
Percepção Espacial
/
Visão Binocular
/
Visão Monocular
/
Percepção de Profundidade
Aspecto:
Equidade e iniquidade
Idioma:
Inglês
Revista:
Psychol. neurosci. (Impr.)
Assunto da revista:
Neurologia
/
Psicologia
Ano de publicação:
2014
Tipo de documento:
Artigo
/
Documento de projeto
País de afiliação:
Espanha
Instituição/País de afiliação:
University of Barcelona/ES