The discovery, called a continuity field, at first seems to be yet another optical illusion.
“The continuity field smoothes what would otherwise be a jittery perception of object features over time,” said David Whitney, associate professor of psychology at UC Berkeley and senior author of the study. “Essentially, it pulls together physically but not radically different objects to appear more similar to each other. This is surprising because it means the visual system sacrifices accuracy for the sake of the continuous, stable perception of objects.”
It actually means that what we do see is, in fact, a mixture of past and present. According to the research, published in the journal Nature Neuroscience, stability is attained at the expense of accuracy.
"What you are seeing at the present moment is not a fresh snapshot of the world but rather an average of what you've seen in the past 10 to 15 seconds," said study author Jason Fischer, Ph.D., a neuroscientist at MIT.
“Even though the sequence of images was random, the participants’ perception of any given image was biased strongly toward the past several images that came before it,” said Fischer, who calls this phenomenon “perceptual serial dependence.”
In a controlled experiment researchers dispersed the gratings on the computer screen. Now that the gratings were far apart from each other, the participants didn’t merge the angles together. This leads to the conclusion that the continuity field effect starts to work only when objects are close to each other.
Fischer and Whitney also underline that “the strength of this [brain] bias was modulated by attention.” Quite obviously, the influence of the gratings lessened as more time passed.
It turns out lots of familiar objects and faces may not be as real as we are used to thinking. The human brain conceals lots of mysteries. Although it has a 15-second delay in perception, the brain can also work incredibly fast. Neuroscientists from MIT recently found that even if the eye sees an image for as little as 13 milliseconds, the brain can still successfully process it.
