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bioRxiv · 10.1101/588566

Easily adaptable head-free training system of macaques for tasks requiring precise measurements of eye position

Kawaguchi, K.·Pourriahi, P.·Seillier, L.·Clery, S.·Nienborg, H.
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Abstract

We describe a modified system for training macaque monkeys without invasive head immobilization on visuomotor tasks requiring the control of eye-movements. The system combines a conventional primate chair, a chair-mounted infrared camera for measuring eye-movements and a custom-made concave reward-delivery spout firmly attached to the chair. The animal was seated head-free inside the chair but the concavity of the spout stabilized its head during task performance. Training on visual fixation and discrimination tasks was successfully performed with this system. Eye-measurements, such as fixation-precision, pupil size as well as micro-saccades were comparable to those obtained using conventional invasive head-fixation methods. The system is inexpensive ([~]$40 USD material cost), easy to fabricate in a workshop (technical drawings are included), and readily adjustable between animals without the need to immobilize or sedate them for these adjustments.\n\nHighlightsO_LIWe developed an approach to train macaque monkeys head-free on visuomotor tasks requiring measurements of eye position\nC_LIO_LIThe setup is inexpensive, easy to build, and readily adjusted to the animal without the need for sedation\nC_LIO_LIThe system was tested for training on a visual fixation and a visual discrimination task\nC_LIO_LIEye measurements (fixation precision, pupil size, microsaccades) were comparable to those from head-fixed animals\nC_LI

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Kawaguchi, K., Pourriahi, P., Seillier, L., Clery, S., Nienborg, H.. 2019-03-26. Easily adaptable head-free training system of macaques for tasks requiring precise measurements of eye position. https://doi.org/10.1101/588566

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