Name: how to create and use binocular rivalry
Uploaded: 2010-11-10T17:10:00
Duration: 14 min 34 s
Description: Watch this Scientific Journal Video about How to Create and Use Binocular Rivalry at JoVE.com

The authors are supported by an International Brain Research Foundation Postdoctoral Fellowship (DC); doctoral training grant T90 DA 022763 (MA); and NIH grant R01-EY017699 and NSF grant BCS-0633281 (SK). The authors are grateful to Randolph Blake for useful comments.

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No conflicts of interest declared.

We have described the nature of binocular rivalry, several methods for creating it, and what considerations must be taken into account when it is used. As detailed in the Introduction, appropriate use of binocular rivalry makes it possible to experimentally address questions regarding the locus (or loci) of awareness, perceptual selection and unconscious processing. To carry out such investigations properly, however, one must be aware of issues such as the importance of maintaining stable vergence, and, if investigating unconscious processing, the necessity of using displays that are likely to yield complete suppression.
When choosing which method to use in order to create rivalry, it is important to take into account the advantages and disadvantages of each method. There is no point, for example, in using red-blue goggles if one is interested in using multi-colored stimuli; but on the other hand, this method is probably the easiest to use in an MRI scanner. Similarly, a mirror stereoscope is a very reliable way of ensuring that separate images fall on corresponding retinal locations; but the individual adjustments required for each observer and the technical difficulties involved in putting a stereoscope in an MRI scanner might make this method less attractive for some studies.
Finally, it is important to be aware of the characteristics of the experience of binocular rivalry in order to employ the appropriate dependent measures. When the research question concerns unconscious processing, independent verification that participants were indeed unaware of the suppressed image is essential. When one is interested in how an experimental manipulation affects dominance and suppression durations, it may be more illuminating to examine the (gamma-shaped) distribution of durations rather than just a central tendency measure such as the mean or median; and it may be important to ascertain whether the observers experienced sharp or gradual (piecemeal or wave-like) transitions of dominance.
We hope researchers interested in employing this fascinating phenomenon will find this introduction helpful.

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how to create and use binocular rivalry

Each of our eyes normally sees a slightly different image of the world around us. The brain can combine these two images into a single coherent representation. However, when the eyes are presented with images that are sufficiently different from each other, an interesting thing happens: Rather than fusing the two images into a combined conscious percept, what transpires is a pattern of perceptual alternations where one image dominates awareness while the other is suppressed; dominance alternates between the two images, typically every few seconds. This perceptual phenomenon is known as binocular rivalry. Binocular rivalry is considered useful for studying perceptual selection and awareness in both human and animal models, because unchanging visual input to each eye leads to alternations in visual awareness and perception. To create a binocular rivalry stimulus, all that is necessary is to present each eye with a different image at the same perceived location. There are several ways of doing this, but newcomers to the field are often unsure which method would best suit their specific needs. The purpose of this article is to describe a number of inexpensive and straightforward ways to create and use binocular rivalry. We detail methods that do not require expensive specialized equipment and describe each method's advantages and disadvantages. The methods described include the use of red-blue goggles, mirror stereoscopes and prism goggles.

Watch this Scientific Journal Video about How to Create and Use Binocular Rivalry at JoVE.com

How to Create and Use Binocular Rivalry

Binocular rivalry occurs when the eyes are presented with different images at the same location: one image dominates while the other is suppressed, and dominance alternates periodically. Rivalry is useful for investigating perceptual selection and visual awareness. Here we describe several easy methods for creating and using binocular rivalry stimuli.

Each of our eyes normally sees a slightly different image of the world around us. The brain can combine these two images into a single coherent ...

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Neuroscience

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How to Build a Laser Speckle Contrast Imaging LSCI System to Monitor Blood Flow

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