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:6/2/2016)... June 2, 2016   The Weather Company , an ... Ads, an industry-first capability in which consumers will be able ... to ask questions via voice or text and receive relevant ... Marketers have long sought an advertising solution ... can be personal, relevant and valuable; and can scale across ...
(Date:6/1/2016)... Favorable Government Initiatives Coupled With ... Identification to Boost Global Biometrics System Market Through 2021  ... report, " Global Biometrics Market By Type, By ... 2011 - 2021", the global biometrics market is projected ... of growing security concerns across various end use sectors ...
(Date:5/20/2016)... May 20, 2016  VoiceIt is excited to ... VoicePass. By working together, VoiceIt and ... VoiceIt and VoicePass take slightly different approaches to ... both security and usability. ... this new partnership. "This marketing and ...
Breaking Biology News(10 mins):
(Date:11/30/2016)... GREENWICH, Connecticut , November 30, 2016 ...   ... Aptuit, LLC today announced ... screening library. An additional 150,000 novel compounds have increased the ... selected to broaden the hit discovery capabilities of the company. ...
(Date:11/30/2016)... ... November 30, 2016 , ... ... technology applications, introduces the 5th generation, ultra-bright, Laser-Driven Light Source, the EQ-77, at ... Source (LDLS™) technology, the EQ-77 offers higher radiance and irradiance from a truly ...
(Date:11/30/2016)... ... , ... With growth rates averaging more than 30% each year, Random42 has ... continuing their expansion in their new office space. The new office has a fantastic ... the creative industries, so Random42 Scientific Communication will fit right in. , Ben ...
(Date:11/30/2016)... November 30, 2016 Teil einer ... ... , Aptuit LLC ... zu haben. Zusätzliche 150.000 neuartige Substanzen haben die Prüfsammlung ... ausgewählt, um die starken Entdeckungsfähigkeiten des Unternehmens zu erweitern. ...
Breaking Biology Technology: