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Dr. Ryan Yoder
Department of Psychology
Indiana University – Purdue University Fort Wayne
The ability to perceive one's position and directional heading within the environment is necessary for accurate navigation. This "spatial" knowledge usually depends on signals from the visual system, but navigation is nearly as accurate in non-spatial environments. Indeed, navigation in both visual and non-visual environments is characterized by speed variations during each segment of a journey – referred to as movement scaling – which suggest an accurate perception of distance and direction traveled relative to a starting point. This perception of distance is thought to depend on functional otolith organs, which sense linear acceleration. We therefore tested whether tilted mice, which have dysfunctional otolith organs, show normal movement scaling on a homing task. The homing task requires the animal to exit a start box and forage for food, after which it carries the food back to the start box for consumption. The return segment is of particular interest because it reflects the ability to use self-movement cues experienced during the foraging segment, which are used to determine the direction that leads back to the start box. Preliminary data suggest that control and tilted mice had similar movement characteristics during foraging, but tilted mice showed altered speed modulation during the return segment. The return segment was also more circuitous than in control mice, suggesting impaired perception of directional heading. These altered movement characteristics in tilted mice suggest the otolith organs contribute to movement scaling during navigation.
Psychology | Social and Behavioral Sciences
Goebel, Elizabeth and Brockman, Sarah, "Otolithic contribution to non-visual navigation" (2014). 2014 IPFW Student Research and Creative Endeavor Symposium. 49.