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Schlagwörter:
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Zusammenfassung:
Berger et al. [1] have shown the general dominance of visual to vestibular perception in a setting
of combined stimulation requiring integration of sensory modalities. In the present study
we evaluate different integration strategies during presentation of dissociated visual-vestibular
stimuli as a function of the individual spacial orientation ability of the subjects. We present the
results of the gymnasts for discussion. The subjects (n = 10, age: 1013, height: 140,33 +/-
4,09, mass: 32,89 +/- 2,32) were rotated in a spherical chamber, with simultaneous presentation
of a planetarium type visual stimulus with an independently controlled velocity. Testing
consisted of a standardized randomized sequence of 26 horizontal rotations in both directions
with different visual-vestibular dissociation factors (the difference between the velocities, normalized
to the rotational velocity). The factors presented were in steps of 0.2 between 1 and
-1, and additionally 2 and -2. Auditory stimuli were blocked using headphones. The rotatory
stimulus consisted of a velocity step of 60deg/s with a duration of 6 seconds. After each turn,
two questions were asked: 1. Which direction did the stars turn in relation to you? (to control
for visual perception and concentration) 2. Which direction did the stars turn in relation to
the room? (to test the visual-vestibular integration). Correlation analysis of correct responses
to question 2 against the individual perrotatory space orientation ability (PSO) as independantly
evaluated by three coaches was performed. Results: A positive correlation between
the visual-vestibular dissociation factors and the number of correct answers to question 2 was
found [Pearson: r = 0,81 with positive dissociation factor (determination coefcient: 0,65); r =
0,81 with negative dissociation factor (determination coefcient: 0,66)]. However, there was a
negative correlation tendency between the ratio of the correct answers and the PSO of the subjects
(Spearman, rank using the coach questionnaires:k=0.60, determination coefcient: 0,36).
Discussion: The rst result corresponds to previous work and demonstrates the dominance of
visual to vestibular perception for lower dissociation factors. More remarkable is the second
result showing the higher the PRO, the worse the ability to determine the stars' direction. The
results require one to consider that perhaps the gymnasts have learned to give a superior weight
to the visual information over the vestibular sensation, not as an integrative strategy, but rather
a form of sensory ltering. This opens the discussion for how best to evaluate the integrative
or ltering abilities of the age-matched group of non-athletes.
