$$News and Reports$$

Mar. 10, 2015
 



 

A recent study by BGU researchers has demonstrated that the way animals move their eyes is essential for processing visual information.   

Vision starts in the eye where the retina, a small neural tissue, converts the image falling on it into electrical signals.  Photoreceptors initially capture the light which is converted into electrical signals. These signals are later transferred by the retina to the brain via the optic nerve which is a bundle of nerve fibers. The photoreceptors outnumber the cells that transmit the information to the brain.  The capacity of the optic nerve is limited and it is considered to be a bottleneck of information transfer. Therefore, the retina must process the image and efficiently encode the information which is passed to the brain.  

A recent theoretical work suggested that microscopic eye movements, executed incessantly by the eye muscles while acquiring visual information, perform critical information-processing functions in vision. Namely, it was proposed that these small eye movements enhance image features to ensure efficient information transfer from retina to the brain. These eye movements were not given appropriate attention previously. 

In a recent study published in PNAS, a group of scientists from the Departments of Life Sciences and Physics at BGU, together with a collaborator from  Boston University, validated for the first time this recently proposed theory by measuring the response of the retina to a movie which replicated the natural input to the retina in the presence and absence of the microscopic eye movements.  

This work provides first direct experimental confirmation of the prediction that the role of the microscopic eye movements is to enhance the information transfer from the eye to the brain. This result contributes to the classical work on information processing in the eye by showing that the patterns of microscopic eye movements contributes to vision prior to any neural processing. 

The study was performed under the guidance of Prof. Ronen Segev from the Department of Life Sciences in his lab. The team includes PhD student Chen Giladi, former MSc student Irina Segal, undergraduate student Yam Kushinsky, Prof. Michael Gedalin from the Department of Physics, PhD student Mor Ben-Tov from Life Sciences, and Dr. Alik Mokeichev from the Department of Computer Sciences together with Prof. Michele Rucci of Boston University.