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Without your brain making constant predictions, images fed to our eyes would be a blur of motion as images move back and forth, back and forth. Yet we are moving our eyes continuously every day, and all day, and we perceive the world to be steady and stable.
In days gone by, researchers thought that the brains predictions had that much control over us that they would cause us to make errors in estimating where objects were positioned.Now a group of neuroscientists are challenging the knowledge we have on coordination between the brain and our eyes using an ' errors of estimation' test incorporating localized flashes of light that takes the form of a random flashing ball on a computer screen,.The researchers wanted to know how predictions on eye movements had been held responsible for localization errors: namely if the prediction did not correspond to the eventual eye movement, a mismatch between what you expected to see and what you actually saw could have been the result.
The test subjects were asked to follow the randomly flashing balls with their eyes while an eye-tracker was used to record the eyes movements. The experiment always ended with one last ball on the monitor, followed by a short flash of light near that ball. The person had to look at the last, stationary ball while using the computer mouse to indicate the position of the flash of light. However, in some cases, a signal was sent around the time the last ball appeared, indicating that the subject was NOT allowed to look at the ball. In other words, the eye movement was cancelled at the last moment. The person being tested still had to indicate where the flash was visible.
They found that the subjects did not make any mistakes in localizing the flash of light even when told at the last minute to not look at the ball demonstrating that you don't make localization errors solely on the basis of prediction.