An analysis of perceptual and cognitive factors in radiographic interpretation.
Detection of small tumors in chest x-ray films was studied under tachistoscopic viewing conditions designed to stimulate single fixations varying in dwell time, found in free search. Two questions were asked: How much dwell time is required to detect a nodule (experiment 1)? How effective are peripheral inputs in the detection of a nodule (experiment 2)? Our findings indicate that a dwell time of 300 ms was sufficient to detect 85% of the nodules when they were viewed directly. Detection accuracy was reduced by one-half when the tumor was located 5 degrees from the axis of gaze. Taken together with data from eye movement experiments, these results provide useful estimates of perceptual and cognitive parameters of visual search.
D003071:Cognition; D005133:Eye Movements; D006801:Humans; D011859:Radiography; D013679:Technology, Radiologic; D013997:Time Factors; D014796:Visual Perception / Q000502:physiology*