Automated quantification of optokinetic responses based on head-movement
© Kretschmer and Kretzberg; licensee BioMed Central Ltd. 2012
Published: 16 July 2012
In computational ethology, the measurement of optokinetic responses (OKR) is an established method  to determine thresholds of the visual system in various animal species. Wide-field movements of the visual environment elicit the typical body, head and eye-movements of optokinetic responses. Experimentally, usually regular patterns, e.g. black and white stripes, are moved continuously. Variation of stimulus parameters like contrast, spatial frequency and movement velocity allows to determine visual thresholds. The measurement of eye-movements is the most sensitive method to quantify optokinetic responses, but typically requires the fixation of the head by invasive surgery. Hence the measurement of head-movements is often used alternatively to rapidly measure the behavior of many individuals. While an animal performs these experiments, a human observer decides for each stimulus presentation if a tracking reaction was observed or not . Since responses of the animals typically are not recorded, off-line analysis and the evaluation of other response characteristics is not possible.
Supported by German research foundation research unit DFG-FOR701.
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