Gaze stabilization reflexes in the mouse: New tools to study vision and sensorimotor integration

Gaze stabilization reflexes in the mouse: New tools to study vision and sensorimotor integration No part of this book may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without permission of the author or, when appropriate, of the scientific journal in which parts of this thesis have been published. Table of Contents Chapter 1 General Introduction 8 Chapter 2 Age‐ and sex‐related differences in contrast 42 sensitivity in C57Bl6 mice Chapter 3 Optomotor impairments in Ercc d‐ mouse 65 mutants Chapter 4 Measuring contrast sensitivity in man using 88 the ocular following response Chapter 5 Three‐dimensional optokinetic eye movements 104 in the C57BL6J mouse Chapter 6 General Discussion 124 Appendix A: How to use eye tracking to measure contrast 136 sensitivity in mice Appendix B: How to measure 3D eye movements in mice 146 using video Oculography Summary 154 Nederlandse samenvatting 156 Dankwoord 160 7 Scope of this thesis Gaze stabilization reflexes are a popular model system in neuroscience for connecting neurophysiology and behavior as well as studying the neural correlates of behavioral plasticity. These compensatory eye movements are one of the simplest motor behaviors, consisting of a more or less spherical object that rotates with three degrees of freedom, without significantly changing the load during a movement trajectory. Additionally, it is a model system where the sensory input, consisting of visual and/or vestibular stimulation, can be fully controlled. The output, reflexive compensatory eye movements and electrophysiological activity, can be recorded and correlated with the sensory input. By manipulating those reflexive eye movements by using different combinations of sensory input, motor learning can be studied in a well‐controlled environment. In this thesis, we describe several innovative approaches that can be added to the neuroscientific arsenal. We are the first lab to describe how to record three dimensional eye movements in mice using video‐oculography. Additionally, we describe how compensatory eye movements can be used to quantify contrast sensitivity; the ability to detect small increments in shades of gray on a uniform background, which is one of the main limiting factors in a wide variety of visual tasks. This new and sensitive method is useful in characterizing mouse models where vision is affected as a result of mutations, aging, retinal degeneration or neurological impairment of the visual system. Introduction Motor learning is the process of improving the smoothness …