ORIENTATION IDENTIFICATION AT DIFFERENT BACKGROUND LEVELS - ITS PRECISION AND DISTORTIONS

Margarita Zlatkova

    Research output: Contribution to journalArticle

    4 Citations (Scopus)

    Abstract

    Orientation identification was studied at high (1000 td) and low (I td) background illuminations. The subject had to estimate in degrees the orientation of a line presented in one of 18 orientations, 10 deg apart. Unlike other spatial discriminations, the precision of orientation judgments was not significantly impaired at low background if a suprathreshold stimulation was used. However, OUT earlier data showed that the identification at threshold was deteriorated at low background level. Different mechanisms of threshold and suprathreshold identification were suggested. The mechanism of suprathreshold identification was thought to contribute to the stability of the orientation perception during adaptation. The deviations of the subjective estimates from real orientations were also studied. The bias of perceived orientation toward the vertical increased at low background. This bias remained the same in egocentric coordinates, when the subjects were in supine position.
    LanguageEnglish
    Pages2073-2081
    JournalVision Research
    Volume33
    Issue number15
    Publication statusPublished - Oct 1993

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    @article{a5472f613eb24e2e9190ea473a9ffb74,
    title = "ORIENTATION IDENTIFICATION AT DIFFERENT BACKGROUND LEVELS - ITS PRECISION AND DISTORTIONS",
    abstract = "Orientation identification was studied at high (1000 td) and low (I td) background illuminations. The subject had to estimate in degrees the orientation of a line presented in one of 18 orientations, 10 deg apart. Unlike other spatial discriminations, the precision of orientation judgments was not significantly impaired at low background if a suprathreshold stimulation was used. However, OUT earlier data showed that the identification at threshold was deteriorated at low background level. Different mechanisms of threshold and suprathreshold identification were suggested. The mechanism of suprathreshold identification was thought to contribute to the stability of the orientation perception during adaptation. The deviations of the subjective estimates from real orientations were also studied. The bias of perceived orientation toward the vertical increased at low background. This bias remained the same in egocentric coordinates, when the subjects were in supine position.",
    author = "Margarita Zlatkova",
    year = "1993",
    month = "10",
    language = "English",
    volume = "33",
    pages = "2073--2081",
    journal = "Vision Research",
    issn = "0042-6989",
    publisher = "Elsevier",
    number = "15",

    }

    ORIENTATION IDENTIFICATION AT DIFFERENT BACKGROUND LEVELS - ITS PRECISION AND DISTORTIONS. / Zlatkova, Margarita.

    In: Vision Research, Vol. 33, No. 15, 10.1993, p. 2073-2081.

    Research output: Contribution to journalArticle

    TY - JOUR

    T1 - ORIENTATION IDENTIFICATION AT DIFFERENT BACKGROUND LEVELS - ITS PRECISION AND DISTORTIONS

    AU - Zlatkova, Margarita

    PY - 1993/10

    Y1 - 1993/10

    N2 - Orientation identification was studied at high (1000 td) and low (I td) background illuminations. The subject had to estimate in degrees the orientation of a line presented in one of 18 orientations, 10 deg apart. Unlike other spatial discriminations, the precision of orientation judgments was not significantly impaired at low background if a suprathreshold stimulation was used. However, OUT earlier data showed that the identification at threshold was deteriorated at low background level. Different mechanisms of threshold and suprathreshold identification were suggested. The mechanism of suprathreshold identification was thought to contribute to the stability of the orientation perception during adaptation. The deviations of the subjective estimates from real orientations were also studied. The bias of perceived orientation toward the vertical increased at low background. This bias remained the same in egocentric coordinates, when the subjects were in supine position.

    AB - Orientation identification was studied at high (1000 td) and low (I td) background illuminations. The subject had to estimate in degrees the orientation of a line presented in one of 18 orientations, 10 deg apart. Unlike other spatial discriminations, the precision of orientation judgments was not significantly impaired at low background if a suprathreshold stimulation was used. However, OUT earlier data showed that the identification at threshold was deteriorated at low background level. Different mechanisms of threshold and suprathreshold identification were suggested. The mechanism of suprathreshold identification was thought to contribute to the stability of the orientation perception during adaptation. The deviations of the subjective estimates from real orientations were also studied. The bias of perceived orientation toward the vertical increased at low background. This bias remained the same in egocentric coordinates, when the subjects were in supine position.

    M3 - Article

    VL - 33

    SP - 2073

    EP - 2081

    JO - Vision Research

    T2 - Vision Research

    JF - Vision Research

    SN - 0042-6989

    IS - 15

    ER -