Perception, Vestibular
Conditions
Keywords
verticality perception
Brief summary
The long-term goal of this research is to advance our knowledge of how the brain combines the information of multiple sensory systems coding for spatial orientation and how adaptation to vestibular imbalance influences spatial orientation. In healthy human subjects verticality perception is accurate while upright. After prolonged roll-tilt, humans show a systematic bias in perceived direction towards the previous roll-tilted position (so-called post-tilt bias). Here we evaluate different potential explanations for this bias using both vision-dependent and vision-independent paradigms of verticality perception.
Interventions
OTHERperception of vertical after static roll-tilt over 5min
subjects will indicate perceived direction of vertical after 5min of static whole-body roll-tilt.
Sponsors
University of Zurich
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
1. ages 18-65 years 2. informed consent 3. absence of
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Adjustment errors and trial-to-trial variability as assessed by line adjustments (subjective visual vertical (SVV)), adjustments of a rod (subjective haptic vertical (SHV)) or self-adjustments (subjective postural vertical (SPV)) after prolonged roll | measurements will be obtained over periods of 5min in a single session and day | In all three paradigms (SVV, SHV and SPV) the percept of direction of gravity will be assessed. Parameters will be adjustment errors (accuracy) and trial-to-trial variability (precision) based on repetitive adjustments of a luminous line (SVV) or a rod (SHV) after returning to upright position after a period of 5min in static roll-tilt at 90° left-ear down or right-ear down. During the roll-tilt period subjects remain either in the dark or observe a rotating optokinetic (random dot) pattern. Individual mean values and standard deviation (SD) will be calculated for all conditions. Adjustments with the joystick (SPV) will start from 90° ear-down positions after 5min of static roll. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Impact of a rotating optokinetic stimulus (velocity 60°/s) on adjustment errors as assessed by the SVV, the SHV or the SPV after 5min of static roll-tilt at +/- 90° roll. | measurements will be obtained over periods of 5min in a single session and day | During the 5min period with static roll at +/- 90deg ear-down positions subjects will be presented a rotating optokinetic stimulus (random dot pattern, clockwise or counter-clockwise rotation) in some conditions. Adjustment errors and trial-to-trial variability of conditions with the optokinetic stimulus will be compared to those without the optokinetic stimulus. |
Outcome results
None listed