Contrast sensitivity, spatial and temporal tuning of the larval zebrafish optokinetic response.
OBJECTIVE
To characterize the quantitative properties of the optokinetic response (OKR) in zebrafish larvae as a tool to test visual performance in genetically modified larvae.


METHODS
Horizontal OKR was triggered in 5-day-old zebrafish larvae by stimulation with projected computer-generated gratings of varying contrast, angular velocity, temporal and spatial frequency, and brightness. Eye movements were analyzed by a custom-made eye tracker based on image analysis.


RESULTS
The gain of the OKR slow phase was dependent on angular velocity, spatial frequency, and contrast of a moving grating, but largely independent on brightness. Eye velocity was a logarithmically linear function of grating contrast with a slope of approximately 0.8 per log unit contrast.


CONCLUSIONS
The OKR of the larval zebrafish is not scaled for stimulus contrast and spatial frequency. These properties make the OKR a valuable tool to quantify behavioral visual performance such as visual acuity, contrast sensitivity, and light adaptation. This behavioral paradigm will be useful for analyzing visual performance in mutant and gene-knockdown larval zebrafish.
Rinner
Oliver
O
Swiss Federal Institute of Technology, Department of Biology, and Brain Research Institute of the University Zurich, Zurich, Switzerland.
Rick
Jens M
JM
Neuhauss
Stephan C F
SC
D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D015350:Contrast Sensitivity / Q000502:physiology*; D007814:Larva / Q000502:physiology; D008027:Light; D017120:Nystagmus, Optokinetic / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*; D015027:Zebrafish / Q000502:physiology*