Apr 3 2005
A new study suggests there may be a better way to sharpen the eyes of radiologists, military pilots and other professionals for whom identifying objects or patterns in a monitor or visual display – often quickly and with pinpoint accuracy – is a critical part of the job.
According to the study, the new approach involves rethinking how the eyes are trained to filter out clutter and focus in on a target. Previously, scientists believed these two perceptual skills intermixed and worked simultaneously. This study, however, demonstrates that they are in fact independent and best practiced in a specific order.
The study, by UCI cognitive scientist Barbara Anne Dosher and USC colleague Zhong-Lin Lu, is published in this week’s Proceedings of the National Academy of Sciences.
“This research demonstrates, for the first time, the independence of these two learning mechanisms, and suggests new methods of training for people who must pinpoint targets in busy images,” Dosher said.
The researchers tested six volunteers with normal vision. Half of the volunteers trained first on clear, or low-clutter, displays, identifying targets or patterns ranging from dim to strong using the “amplification” or focusing in process. Then they trained on “noisy,” or high-clutter, displays, exercising their filtering mechanism. The other three volunteers started with the noisy displays and then switched to clear. Over five days, the volunteers made nearly 4,000 practice judgments in each condition, with accuracy measured every 180 trials.
The researchers found that those who first trained on the clear displays approximately doubled their efficiency and transferred their improved performance to the cluttered displays immediately. Those that first trained on the cluttered displays did not show any transferred improvement when they tested on the clear displays.
“We were surprised to find training the eyes in the one process would transfer so extensively to the other, but not vice versa,” Dosher said.
Dosher and Lu have been working in visual attention and perceptual learning for nearly six years. In addition to shedding light on perceptual learning processes, their testing methods and models have been used to evaluate the processing limitation of people with visual deficits.
Funding for this research came from the National Institutes of Mental Health, the National Science Foundation and the Air Force Office of Scientific Research.
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