Characterizing the development of visual search expertise in pathology residents viewing whole slide images.

The goal of this study was to examine and characterize changes in the ways that pathology residents examine digital whole slide images as they progress through the residency training. A series of 20 digitized breast biopsy whole slide images (half benign and half malignant biopsies) were individually shown to 4 pathology residents at four points in time--at the beginning of their first, second, third, and fourth years of residency. Their task was to examine each image and select three areas that they would most want to zoom in on in order to view the diagnostic detail at higher resolution. Eye position was recorded as they scanned each whole slide image at low magnification. The data indicate that with each successive year of experience, the residents' search patterns do change. Overall, with time, it takes significantly less time to view an individual slide and decide where to zoom, significantly fewer fixations are generated overall, and there is less examination of nondiagnostic areas. Essentially, the residents' search becomes much more efficient. These findings are similar to those in radiology, and support the theory that an important aspect of the development of expertise is improved pattern recognition (taking in more information during the initial Gestalt or gist view) as well as improved allocation of attention and visual processing resources. Progression in improvements in visual search strategies was similar, but not identical, for the 4 residents.