Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


New Evidence of an Unrecognized Visual Process

We don’t see only what meets the eye. The visual system constantly takes in ambiguous stimuli, weighs its options, and decides what it perceives. This normally happens effortlessly. Sometimes, however, an ambiguity is persistent, and the visual system waffles on which perception is right. Such instances interest scientists because they help us understand how the eyes and the brain make sense of what we see.

Most scientists believe rivalry occurs only when there’s “spatial conflict”—two objects striking the same place on the retina at the same time as our eyes move. But the retina isn’t the only filter or organizer of visual information. There’s also the “non-retinal reference frame”—objects such as mountains or chairs that locate things in space and make the world appear stable even when our eyes are moving.

“We asked: what if visual ambiguities are not presented on the same spot on the retina, but on the objects [in the frame] as they move around,” says California Institute of Technology cognitive scientist Jeroen J.A. van Boxtel. Indeed, he and colleague Christof Koch found evidence of rivalry in this reference frame, with surprising effects on the better-understood spatial conflict. The findings, which will appear in an upcoming issue of Psychological Science, a journal published by the Association of Psychological Science, offer intriguing clues to how the visual system works.

In their experiments, van Boxtel and Koch created spatial conflict with a “motion quartet,” which changes the arrangement of four dots. If the dots are displaced in certain ways, the visual system isn’t sure if the movement is vertical or horizontal. If the dots move to an altogether different space, there’s no rivalry. Then the researchers upped the perceptual ante by creating an object reference frame with three white discs and shifting it, too, along with or in opposition to the smaller dots.

Seven male and female participants viewed the changing arrangements in four conditions. In one, both dots and discs remained stationary (creating spatial rivalry); in each of two, either dots or discs moved right or left; in the fourth, both moved horizontally together (creating ambiguity in the frame). Each time, participants had to press a button indicating whether the dots moved horizontally or vertically. The presses were analyzed for perceived movement “bias” (more horizontal or vertical) and duration—evidence either of rivalry or visual clarity.

The results: Even when the dots moved to another space altogether—so there was no spatial conflict—the moving discs created the effect of perceptual ambiguity. But the researchers also found that visual rivalry disappeared when the dots were stationary and the disks moved (that is, the dots were not linked to the disks). It was as if the brain had bigger fish—object-frame rivalry—to fry.

In subsequent experiments—one changing the vertical relationship of the dots and one placing the dots outside the white discs—the researchers got results similar to those they would have gotten without the frame. Their conclusion: The visual system is working out object-frame rivalry as it would spatial rivalry, probably with the same brain regions and processes.

For more information about this study, please contact: Jeroen J. A. van Boxtel at

The APS journal Psychological Science is the highest ranked empirical journal in psychology. For a copy of the article "Visual rivalry without spatial conflict" and access to other Psychological Science research findings, please contact Divya Menon at 202-293-9300 or

Divya Menon | EurekAlert!
Further information:

More articles from Health and Medicine:

nachricht Resolving the mystery of preeclampsia
21.10.2016 | Universitätsklinikum Magdeburg

nachricht New potential cancer treatment using microwaves to target deep tumors
12.10.2016 | University of Texas at Arlington

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>