Karl F. Van Orden

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BACKGROUND It is unclear whether and how elite athletes process physiological or psychological challenges differently than healthy comparison subjects. In general, individuals optimize exercise level as it relates to differences between expected and experienced exertion, which can be conceptualized as a body prediction error. The process of computing a body(More)
Extreme environments requiring optimal cognitive and behavioral performance occur in a wide variety of situations ranging from complex combat operations to elite athletic competitions. Although a large literature characterizes psychological and other aspects of individual differences in performances in extreme environments, virtually nothing is known about(More)
Five concurrent eye activity measures were used to model fatigue-related changes in performance during a visual compensatory tracking task. Nine participants demonstrated considerable variations in performance level during two 53-min testing sessions in which continuous video-based eye activity measures were obtained. Using a trackball, participants were(More)
Foveal increment thresholds were measured in young, middle-aged, and older observers. These thresholds, which involved the detection of a small test flash as a function of the intensity of a larger background adapting field (AF), were measured at the instant of onset of the AF (transient condition) and when the eye had been fully light adapted to the AF(More)
BACKGROUND Little is known about the neural basis of elite performers and their optimal performance in extreme environments. The purpose of this study was to examine brain processing differences between elite warfighters and comparison subjects in brain structures that are important for emotion processing and interoception. METHODOLOGY/PRINCIPAL FINDINGS(More)
Three visual search experiments evaluated the benefits and distracting effects of using luminance and flashing to highlight subclasses of symbols coded by shape and color. Each of three general shape/color classes (circular/blue, diamond/red, square/yellow) was divided into three subclasses by presenting the upper half, lower half, or entire symbol.(More)
Understanding the neural processes that characterize elite performers is a first step to develop a neuroscience model that can be used to improve performance in stressful circumstances. Adventure racers are elite athletes that operate in small teams in the context of environmental and physical extremes. In particular, awareness of team member's emotional(More)
A brightness estimation experiment was conducted on 10 old (ages 60 to 77) and 10 young (ages 22 to 27) volunteers. Participants were introduced to magnitude estimation by scaling the lengths of line stimuli, after which they dark adapted for 10 minutes. Stimuli for brightness estimation were presented binocularly via a free-viewing system and consisted of(More)
The extent to which pattern reversal evoked potential amplitudes are distributed symmetrically over the scalp was investigated as a function of stimulus spatial frequency. Nine right-handed male subjects viewed sinusoidal grating stimuli of 4.0 and 0.5 c/deg phase reversed every 900 msec. A visual half-field configuration enabled selective stimulation of(More)