New York, June 18 (IANS): As city streets become increasingly crowded with distractions, our ability to process visual information remains unchanged. Can modern eyes keep up?
A new study suggests that even as we process a million things at once, we still remain sensitive to certain changes in our visual environment - even while performing a difficult task.
Researchers from Concordia University, Kansas State University, the University of Findlay, the University of Central Florida, and the University of Illinois prove that we can automatically detect changes in blur across our field of view.
"Blur is normally compensated for by adjusting the lens of the eye to bring the image back into focus," said study co-author Aaron Johnson, professor of psychology at Concordia University.
To investigate, the research team focused on the common problem of blurred sight, which can be caused by factors like changes in distance between objects, as well as vision disorders like near-sightedness, far-sightedness and astigmatism.
The researchers showed that study participants (individuals with normal, or corrected-to-normal, vision) looked at 1,296 distinct images - pictures of things ranging from forests to building interiors - and used a window that moved based on the their eye movements to give the pictures two levels of resolution.
As they changed the resolution from blurry to sharp, the researchers gave participants mental tasks of varying degree of difficulty.
Regardless of the difficulty levels, though, the subjects' ability to detect blur in these pictures was unchanged.
"Our study proves that, much like other simple visual features such as colour and size, blur in an image does not seem to require mental effort to detect," Johnson added in a paper published in the journal Visual Cognition.