Navigation Links
Shape encoding may start in the retina
Date:9/11/2007

Los Angeles New evidence from the University of Southern California suggests that there may be dedicated cells in the retina that help compile small bits of information in order to recognize objects. The research was conducted by Ernest Greene, professor of psychology in the area of brain and cognitive sciences at USC. The study is published in the Public Library of Science journal, PLoS ONE.

It is well established that the images the observer sees are divided in half as they are sent to the two hemispheres of the brain. When a person looks at the center of an object, the image from the right half of the object will be sent to one hemisphere of the brain and the image of the left half is sent to the other. This is true whether a person uses one eye or two to look at the object. Given that the primary visual areas in each hemisphere are seeing only half of the object, it has been assumed that communication between the hemispheres was needed to combine the information, said Greene.

By using a high-speed LED array to display the images, Greene found evidence that the two sides of the retina interact to enhance the effectiveness of shape cues, which he describes as linkage. The cells in the retina appear to be coordinating their responses in a way that benefits shape recognition. Further, they do so with unexpected temporal precision.

The study was done by positioning dots around the outer boundaries of objects, forming stimuli similar to silhouettes. The dots were shown, in successive pairs, one pair after the other, and the observers were then asked to identify each shape. Recognition was best if time intervals that separated pairs and pair members were in the submillisecond range. This was true whether both members of the pair were displayed on the same side of the object or on opposite sides. This finding suggests that the responses from the two sides of the retina are being linked in some manner, and the process of joining the two halves of an object is not done only in the brain, says Greene.

It is unlikely that the nerve signal being sent from the eye to the brain can be precise enough to preserve submillisecond timing differences, says Greene. Also, for the brain to coordinate nerve signals being sent from opposite sides of the retina, communication between the two hemispheres would be needed. It strains credulity that these additional processing steps could be accomplished while preserving submillisecond precision in the responses to pair members, Greene says. He thinks it is more likely that cell structures in the retina link the responses prior to sending the information to the visual cortex. The retina itself may be assessing global relationships among boundary locations, these operations being required for recognition of the shape.


'/>"/>

Contact: Ernest Greene
egreene@usc.edu
818-353-4051
Public Library of Science
Source:Eurekalert

Related biology news :

1. Elusive HIV shape change revealed; Key clue to how virus infects cells
2. Discovery of key proteins shape could lead to improved bacterial pneumonia vaccine
3. The Shapes Of Life: NIGMS Project Yields More Than 1,000 Protein Structures
4. Fibril Shape Is The Basis Of Prion Strains And Cross-species Prion Infection
5. Scientists reveal the shape of a protein that helps retroviruses break into cells
6. Evolution of taste receptor may have shaped human sensitivity to toxic compounds
7. Divergent life history shapes gene expression in brains of salmon
8. Beyond genes: Lipid helps cell wall protein fold into proper shape
9. Mechanism regulating tooth shape formulation found
10. MicroRNAs have shaped the evolution of the majority of mammalian genes
11. The shape of things to come: Morphology database going global
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/8/2017)... 8, 2017 About Voice Recognition Biometrics Voice ... it against a stored voiceprint template. Acoustic features ... and tone are compared to distinguish between individual ... as most PCs already have a microphone and ... recognition biometrics are most likely to be deployed ...
(Date:2/8/2017)... Report Highlights ... The global synthetic-biology market reached nearly $3.9 billion in ... a compound annual growth rate (CAGR) of 24.0% through 2021. ... for synthetic biology. - Analyses of global market trends, with ... annual growth rates (CAGRs) through 2021. - Coverage of core ...
(Date:2/8/2017)... Report Highlights The global biosurgery market should ... 2016 at a compound annual growth rate (CAGR) of ... An overview of the global market for biosurgery. - ... and 2016, and projections of compound annual growth rates ... the basis of product type, source, application, and region. ...
Breaking Biology News(10 mins):
(Date:2/23/2017)... , Feb. 23, 2017  Imanis Life ... product line of oncolytic vaccinia viruses for virotherapy ... as part of Genelux,s proprietary, vaccinia virus-based technology ... excited to enter into a partnership with Genelux ... oncolytic vaccinia viruses for use in research," said ...
(Date:2/23/2017)... ... 23, 2017 , ... The Greater Gift Initiative, Inc , (GGI) a ... Research . GGI's mission is to advance global health and highlight the greater good ... honor of each clinical trial volunteer. The vision of GGI is to serve as ...
(Date:2/22/2017)... , Feb. 22, 2017  Aratana Therapeutics, Inc. (NASDAQ: ... and commercialization of innovative biopharmaceutical products for companion animals, will ... at 8:30 a.m. ET to discuss financial results from the ... Interested participants and investors may access the ... ...
(Date:2/22/2017)... ... February 22, 2017 , ... ... the leading medical education provider of women’s health, primary care, and specialty ... Council for Continuing Medical Education (ACCME). ACCME’s Accreditation with Commendation is a ...
Breaking Biology Technology: