Research Highlights

• Subject Category:
  • Neuroscience

Published online: 30 April 2008 | doi:10.1038/nchina.2008.96

Visual perception: Turning down the blurry

Wei Zeng

Introduction

© (2008) istockphoto.com/Goran Bogicevic

In digital photography, cameras are often equipped with stabilization technology, which prevents motion blur in the images. Similarly, the brains of humans and many other animals have neural circuits that control vision stability; the neural circuit signals visual neurons in the retina to ignore any blurry images captured by the eyes as they rapidly move about and search for a point of interest. Shurong Wang at the Chinese Academy of Sciences in Beijing and co-workers¹ have unravelled the neural circuit responsible for vision stability in a pigeon during rapid eye movement.

The researchers recorded the activity of 302 visual neurons of a pigeon before, during and after rapid eye movement. They observed that different visual neurons were activated or inhibited at these three stages of eye movement, forming a dynamical and hierarchical neural circuit.

During rapid eye movement, almost all of the visual neurons were inactivated. Once the eyes became stationary, most visual neurons became activated again. Further experiments showed that such orchestrated visual neuron activity was achieved through the transfer and processing of not only movement signals, but also through the approximate copy of these signals (corollary discharges).

When brain stem neurons signal eye muscles to begin movement, they also send a copy of the signals to optokinetic neurons, which tell the visual neurons to ignore any blurry images.

The finding shows how our visual perception system is designed to assure a clear and stable image. It has implications for the design of robots with sophisticated visual perception.

The authors of this work are from:
Laboratory for Visual Information Processing, State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.

Reference

1. Yang, Y., Cao, P., Yang, Y. & Wang, S. R. Corollary discharge circuits for saccadic modulation of the pigeon visual system. Nature Neurosci. doi: 10.1038/nn.2107 (2008). | Article |