PBS Colloquium

Dartmouth Events

PBS Colloquium

Dora Angelaki, Baylor College of Medicine

Friday, November 18, 2016
Moore B03
Intended Audience(s): Public
Categories: Lectures & Seminars

Please join us in Moore BO3 on Friday, November 18, 2016, at 4 p.m., as Dora Angelaki, Professor of Neuroscience at Baylor College of Medicine, presents  “An Internal Model of Gravity and its Role in Spatial Orientation."

Abstract:  Whether running to catch a ball or turning to reach for a cup of coffee, the ability to navigate in the world and interact with the environment depends critically on knowing our current motion and allocentric orientation in the world. Motion sensors in the vestibular inner ear play a particularly important role in this process. However, moving in a gravitational environment complicates estimation of these signals. As pointed out by Einstein over a century ago, all acceleration sensors, including the otolith organs, also respond to the force of gravity. Although illusions can occur when there are insufficient sensory cues available, under most circumstances the brain can accurately distinguish between tilting relative to gravity and translating through space, even in the absence of vision. We have identified a network of neurons in the macaque vestibulo-cerebellum that appears to perform the required computations by using multimodal sensory information from both sets of vestibular sensors to compute an internal model of gravity. Gravity signals have also been found in anterior thalamus neurons that encode 3D head orientation. This tuning is gravity-anchored, and occurs during passive motion in both dark and light conditions. These gravity signals are used to estimate visual orientation in the allocentric world, and bilateral labyrinthectomy causes deficits in both allocentric visual orientation perception and vertical arm movement planning and execution.

A reception will follow outside of Moore 202. 

For more information, contact:
Michelle Powers

Events are free and open to the public unless otherwise noted.