High-fidelity color characterization in virtual reality across head mounted displays, game engines, and materials.

We present a comprehensive colorimetric analysis of three head mounted displays (HMDs) - HTC Vive Pro Eye, Pimax 8K X DMAS, and Varjo Aero - focusing on their color calibration and uniformity across different game engines (Unity and Unreal) and for different materials/shaders. We developed a robust methodology combining hardware and software tools, including spectroradiometry and imaging colorimetry, to characterize and calibrate these HMDs for accurate color reproduction. The study showcases substantial advancements in colorimetric accuracy, with a reduction in the average deltaE00 of 90 or more across all tested HMDs and conditions.

Oculomotor routines for perceptual judgments.

In everyday life we frequently make simple visual judgments about object properties, for example, how big or wide is a certain object? Our goal is to test whether there are also task-specific oculomotor routines that support perceptual judgments, similar to the well-established exploratory routines for haptic perception. In a first study, observers saw different scenes with two objects presented in a photorealistic virtual reality environment. Observers were asked to judge which of two objects was taller or wider while gaze was tracked.

The Statistics of Eye Movements and Binocular Disparities during VR Gaming: Implications for Headset Design.

The human visual system evolved in environments with statistical regularities. Binocular vision is adapted to these such that depth perception and eye movements are more precise, faster, and performed comfortably in environments consistent with the regularities. We measured the statistics of eye movements and binocular disparities in virtual-reality (VR) - gaming environments and found that they are quite different from those in the natural environment.

Hiding the Rabbit: Using a genetic algorithm to investigate shape guidance in visual search.

During visual search, attention is guided by specific features, including shape. Our understanding of shape guidance is limited to specific attributes (closures and line terminations) that do not fully explain the richness of preattentive shape processing. We used a novel genetic algorithm method to explore shape space and to stimulate hypotheses about shape guidance.

Fixational stability as a measure for the recovery of visual function in amblyopia.

People with amblyopia have been shown to have decreased fixational stability, particularly those with strabismic amblyopia. Fixational stability and visual acuity have been shown to be tightly correlated across multiple studies, suggesting a relationship between acuity and oculomotor stability. Reduced visual acuity is the sine qua non of amblyopia, and recovery is measured by the improvement in visual acuity.

Comparing search patterns in digital breast tomosynthesis and full-field digital mammography: an eye tracking study.

As a promising imaging modality, digital breast tomosynthesis (DBT) leads to better diagnostic performance than traditional full-field digital mammograms (FFDM) alone. DBT allows different planes of the breast to be visualized, reducing occlusion from overlapping tissue. Although DBT is gaining popularity, best practices for search strategies in this medium are unclear.

Even if I showed you where you looked, remembering where you just looked is hard.

People know surprisingly little about their own visual behavior, which can be problematic when learning or executing complex visual tasks such as search of medical images. We investigated whether providing observers with online information about their eye position during search would help them recall their own fixations immediately afterwards. Seventeen observers searched for various objects in "Where's Waldo" images for 3 s.

Image toggling saves time in mammography.

When two images are perfectly aligned, even subtle differences are readily detected when the images are "toggled" back and forth in the same location. However, substantial changes between two photographs can be missed if the images are misaligned ("change blindness"). Nevertheless, recent work from our lab, testing nonradiologists, suggests that toggling misaligned photographs leads to superior performance compared to side-by-side viewing (SBS).

Memory and incidental learning for visual frozen noise sequences.

Five experiments explored short-term memory and incidental learning for random visual spatio-temporal sequences. In each experiment, human observers saw samples of 8 Hz temporally-modulated 1D or 2D contrast noise sequences whose members were either uncorrelated across an entire 1-s long stimulus sequence, or comprised two frozen noise sequences that repeated identically between a stimulus' first and second 500 ms halves ("Repeated" noise). Presented with randomly intermixed stimuli of both types, observers judged whether each sequence repeated or not.