Study of transitions in binocular rivalry

FWF Project 10.55776/P33322

What is binocular rivalry?

Human eyes always receive identical visual images. Regardless of whether we look at the world with the right or the left eye, the image we see remains the same. If the paradigm of binocular rivalry is applied, this situation can be changed. Binocular rivalry is a visual illusion that occurs when each eye is shown a different image. The visual system cannot combine different images into one. The viewer alternately perceives either one image or the other. However, there are very short transitional phases between the two images in which a combination of two images can be perceived. Although the external visual image is always the same, the observer's subjective perception changes during binocular rivalry. Binocular rivalry is therefore often used to investigate the origin of consciousness in the brain.

In the illustration on the right, you can see a visualisation of subjective perception in binocular rivalry using the example of two line patterns. For example, the left eye is presented with the grid tilted to the left and the right eye with the grid tilted to the right. Although the visual input does not change, your subjective visual perception could, for example, change continuously as shown in the illustration on the right.
If the GIF does not move automatically, you can see the visualisation by clicking on the image.

Relevance of studying binocular rivalry

Recently, there has also been increasing interest in binocular rivalry in the context of neuropsychiatric disorders. In people with autism and ADHD (attention deficit and hyperactivity disorder), there are longer transitions between the two images in binocular rivalry than in control subjects. The longer the transitions last, the more pronounced the symptoms of the respective disorder.

In the illustration on the right, you can see a visualisation of subjective perception in binocular rivalry using the example of two images (face & house). For example, the image of the house is presented to the left eye and the image of the face to the right eye. Although the visual input does not change, your subjective visual perception could, for example, change continuously as shown in the illustration on the right.
If the GIF does not move automatically, you can see the visualisation by clicking on the image.

Short description of the project

Previous studies have regarded the transition phases as a uniform phenomenon. However, there is clear evidence that there are several types of transitions. These different transitions presumably have different characteristics. In this project, we will systematically investigate the diversity of transitions between the two images during binocular rivalry. We will determine the types of transitions and investigate the experimental factors that shape the appearance of the transitions. This project will advance our understanding of the phenomenon of binocular rivalry, and thus of the neural mechanisms of consciousness. In addition, knowledge of the transition types and their properties is important for further research into neuropsychiatric disorders such as ADHD and autism.