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Boundary conditions for perception of biological motion were explored with the use of computer-generated point-light animation sequences. Perception of this unique form of structure from motion is immune to variations in dot contrast polarity, dot disparity, and spatial-frequency filtering. Biological motion is perceived in texture-defined animation sequences that presumably stimulate only second-order motion pathways, and it is undisturbed by dichoptic presentation of portions of the animation tokens separately to the two eyes.

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Neuroimaging technologies, such as functional nearinfrared spectroscopy (fNIR), could provide performance metrics directly from brain-based measures to assess safety and performance of operators in high-risk fields. In this paper, we objectively and subjectively examine the cognitive workload of air traffic control specialists utilizing a next-generation conflict resolution advisory. Credible differences were observed between continuously increasing workload levels that were induced by increasing the number of aircraft under control. In higher aircraft counts, a possible saturation in brain activity was realized in the fNIR data. A learning effect was also analyzed across a three-day/nine-session training period. The difference between Day 1 and Day 2 was credible, while there was a noncredible difference between Day 2 and Day 3. The results presented in this paper indicate some advantages in objective measures of cognitive workload assessment with fNIR cortical imaging over the subjective workload assessment keypad.Index Terms-Air traffic control, functional near-infrared spectroscopy (fNIR), human performance assessment, near-infrared spectroscopy, optical brain imaging, workload.

Modernization of Air Traffic Control (ATC) display systems includes increased use of color to code information. While colors can enhance display designs, human factors issues like legibility and salience manipulation are still problematic. Here, we address some of the potential usability issues with integrating traffic and advanced weather information on controller displays. We argue that color palettes that are not specifically designed for layered data and a large number of objects can create legibility and salience problems. We discuss the use of luminance contrast to manipulate salience and present some empirical data showing that air traffic controllers display large individual differences in their preferred brightness settings. We argue that user adjustments of luminance contrast for salience manipulation must be severely constrained in future ATC displays. We present a prototype color palette that uses color-coding to prioritize display information while maintaining good legibility.

When observers see motion that is not really there, they can nonetheless show evidence of motion priming. And when observers do not see motion that is really there, they also show evidence for motion priming. Evidently, the process responsible for establishing motion correspondence is sensitive to contextual information, and this sensitivity is modulated at preconscious levels of visual analysis.

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The effect of basic motion structures on perceptual grouping was studied with five-dot motion patterns. Four basic motion structures were identified in terms of proximal common and relative motion vectors. In a forced-choice situation, the observers had to decide to which of two pairs of dots a fifth critical dot seemed to belong. Thus, one of two possible three-dot units was chosen by the observers. The two possible three-dot units defined different motion structures, and the chosen motion structure was considered to have stronger grouping power than the alternative structure had. It was found that parallel common motions (perceived translation in the plane) had the strongest grouping power; these were followed by circular common motions (perceived rotation in the plane), concurrent relative motions (perceived translation in depth), and, finally, parallel relative motions (perceived rotation in depth). The results also suggested effects of proximity and orientation of axis of rotation. It is further argued that the relative grouping power of the motion structures could not solely be interpreted in terms of changes of directions and distances between the dots. Instead it is suggested that vector analysis is a fundamental perceptual activity and that basic motion structures determine grouping power.