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Changes in spatial selectivity of pattern-ERG components with stimulus contrast.

M Korth·R Rix
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Abstract

Electrical mass responses of the visual system to stripe patterns of varying fineness (spatial frequency) can show either an amplitude maximum at a medium spatial frequency, a behavior termed "spatial selectivity," or a monotonic decrease in amplitude with increasing spatial frequency. The former behavior is probably mediated by neurons having a center-surround receptive field structure and the latter by neurons lacking this antagonism. The pattern-evoked human electroretinogram was studied in this report using different spatial frequencies and pattern contrasts. The positive component of the response showed a spatial selectivity only at low contrast but was not spatially selective at the highest contrast. The negative component showed a spatial selectivity at all contrast levels. The data indicate that if pattern-related responses activated by antagonistic receptive fields are to be studied, low contrast values should be employed and attention should be paid to the negative component of the response.

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ElectroretinographyEvoked Potentials, VisualHumansMaleSpace PerceptionVisual PerceptionJournal Article

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M Korth, R Rix. 1985. Changes in spatial selectivity of pattern-ERG components with stimulus contrast.. https://doi.org/10.1007/bf02150569

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