18 research outputs found

    Adverse effects of anxiety on attentional control differ as a function of experience: A simulated driving study

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    This study tested whether adverse effects of state anxiety on attention and performance may be modulated by experience. Sixteen experienced and eleven inexperienced drivers drove in a simulator under low- and high-stress conditions. Anxiety was manipulated by competition, the presence of an evaluator, external video camera, and traffic noise. Most drivers showed greater anxiety scores and higher mean heart rates following manipulation. In both groups increased state anxiety decreased car speed control and caused more collisions, accompanied by fewer fixations of longer duration towards the driving lane across a horizontally narrower region. Inexperienced drivers increased the number of short fixations towards cars, while experienced drivers increased the number of short fixations on the speedometer. Although anxiety impairs processing efficiency and performance effectiveness for both groups, attentional changes differ as a function of experience. Inexperienced drivers tended to shift attention to threatening stimuli, while experienced drives were more likely to consciously monitor task goal

    The influence of anxiety on visual entropy of experienced drivers

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    This study tested the use of entropy to identify changes on behavior of drivers under pressure. Sixteen experienced drivers drove in a simulator wearing a head-mounted eye tracker under low- and high-anxiety conditions. Anxiety was induced by manipulating some psychological factors such as peer-pressure. Fixations transitions between AOIs (lane, speedometer and mirrors) were calculated through first-order transition matrix, transformed to Markov probability matrix and adjusted into the entropy equation. Drivers showed greater state-anxiety scores and higher mean heart rates following manipulation. Under anxiety, drivers showed higher visual entropy, indicating a more random scanning. The randomness implies into a poorer acquisition of information and may indicate an impaired top-down control of attention provoked by anxiety

    Perception-action coupling in infants with down syndrome: Effects of experience and practice

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    This study examined the effects of experience and practice on the coupling between visual information and trunk sway in infants with Down syndrome (DS). Five experienced and five novice sitters were exposed to a moving room, which was oscillated at 0.2 and 0.5 Hz. Infants remained in a sitting position and data were collected on the first, fourth, and seventh days. On the first day, experienced sitters were more influenced by room oscillation than were novices. On the following days, however, the influence of room oscillation decreased for experienced but increased for novice sitters. These results suggest that the relationship between sensory information and motor action in infants with DS can be changed with experience and practice

    Gain and phase between visual stimulus and body sway.

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    <p>Gain (A) and phase values (B) for each age group (4-, 8- and 12-year-old and young adults) across all trials. Values are mean ± SD.</p

    Mean sway amplitude.

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    <p>Mean sway amplitude values of each age group (4-, 8- and 12-year-old and young adults) at room’s stationary trial at anterior-posterior (AP) and medio-lateral (ML) directions (A) and lower and higher-amplitude trials at anterior-posterior (AP) direction (B). Values are mean ± SD. </p

    Visual information and body sway coupling in infants during sitting acquisition

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    The purpose of this study was to examine if there is any developmental change in the coupling between visual information and trunk sway in infants as they acquire the sitting position. Twenty-four infants distributed in four groups (6-, 7-, 8-, and 9-month-old) were sat inside a moving room that oscillated back and forward at frequencies of 0.2 and 0.5 Hz. The results revealed that trunk sway matched to the moving room at both frequencies but did not differ among the four age groups. Coherence and gain revealed that the coupling was weaker at 0.2 than at 0.5 Hz. Relative phase showed that at 0.2 Hz, infants were swaying with no lag but at 0.5 Hz they were lagging the room. These results showed that the coupling between visual information and trunk sway in infants varies with the visual stimulus but does not change as infants acquire the sitting position. © 2001 Elsevier B.V
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