Temporal adaptability and the inverse relationship to sensitivity: a parameter identification model.

Keith Langley

doi:10.1163/1568568054389651

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Temporal adaptability and the inverse relationship to sensitivity: a parameter identification model.

Keith Langley

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Abstract

Following a prolonged period of visual adaptation to a temporally modulated sinusoidal luminance pattern, the threshold contrast of a similar visual pattern is elevated. The adaptive elevation in threshold contrast is selective for spatial frequency, may saturate at low adaptor contrast, and increases as a function of the spatio-temporal frequency of the adapting signal. A model for signal extraction that is capable of explaining these threshold contrast effects of adaptation is proposed. Contrast adaptation in the model is explained by the identification of the parameters of an environmental model: the autocorrelation function of the visualized signal. The proposed model predicts that the adaptability of threshold contrast is governed by unpredicted signal variations present in the visual signal, and thus represents an internal adjustment by the visual system that takes into account these unpredicted signal variations given the additional possibility for signal corruption by additive noise.

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Adaptation, Ocular Computer Simulation Contrast Sensitivity Humans Models, Biological Pattern Recognition, Visual Photic Stimulation Sensory Thresholds Comparative Study Journal Article

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Keith Langley. 2005. Temporal adaptability and the inverse relationship to sensitivity: a parameter identification model.. https://doi.org/10.1163/1568568054389651

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