PERCEPTUAL ENHANCEMENT OF TUMOR TARGETS IN CHEST-X-RAY IMAGES

Under tachistoscopic viewing conditions, precuing the location of pote ntial lung tumor targets in chest X-ray images was less effective than precuing followed by bounding the region of interest (ROI) with a cir cle directly on the image. Detection performance increased as the imag e was systematically masked so that its size approximated that of the circled ROI. When viewing time was extended to allow shifts in eye pos ition, circling the ROI was found to restrict the dispersion of fixati ons and increase the accuracy of fixating the target tumor. When targe ts were placed outside the ROI, the circle inhibited their detection r elative to detection of targets inside the circled region. These findi ngs suggest that cuing by circling restricts target detection to the R OI, and by doing so reduces the interfering effects of outside distrac tors that compete with the target for attention.