Kinaesthetic and visual perceptions of orientations

Information, Organisation et Action, EA 4260, UFR STAPS, University of Caen Basse Normandie, 14032 Caen Cedex, France.
Perception (Impact Factor: 1.11). 01/2009; 38(7):988-1001. DOI: 10.1068/p6132
Source: PubMed

ABSTRACT In the present study we compare the kinaesthetic and visual perception of the vertical and horizontal orientations (subjective vertical and subjective horizontal) to determine whether the perception of cardinal orientations is amodal or modality-specific. The influence of methodological factors on the accuracy of perception is also investigated by varying the stimulus position as a function of its initial tilt (clockwise or counterclockwise) and its angle (22 degrees, 45 degrees, 67 degrees, and 90 degrees) in respect to its physical orientation. Ten participants estimated the vertical and horizontal orientations by repositioning a rod in the kinaesthetic condition or two luminous points, forming a 'virtual line' in the visual condition. Results within the visual modality replicated previous findings by showing that estimation of the physical orientations is very accurate regardless of the initial position of the virtual line. In contrast, the perception of orientation with the kinaesthetic modality was less accurate and systematically influenced by the angle between the initial position of the rod and the required orientation. The findings question the assumption that the subjective vertical is derived from an internal representation of gravity and highlight the necessity of taking into account methodological factors in studies on subjective orientations.


Available from: François Jouen, Apr 21, 2015
  • [Show abstract] [Hide abstract]
    ABSTRACT: The 'bucket test' may indicate that patients with known vestibular disorders have spatial orientation deficits but due to the low receiver operating characteristics (ROC) values it is not useful for screening people for vestibular impairments. 1) to verify that patients with unilateral peripheral vestibular weakness (UW) differ from normal subjects on the bucket test, 2) to determine if patients with unilateral benign paroxysmal positional vertigo (BPPV) differ from normal subjects, 3) to determine the sensitivity and specificity of the test. Patients with UW (n = 25) and BPPV (n = 25) were compared to normals (n = 50). Subjects looked into a clean bucket with a vertical line on the bottom, which rested on a table. It was rotated, clockwise or counterclockwise, for three trials per direction until the subject indicated that the line was vertical. The dependent measure was the mean absolute value of the deviations from the true vertical. Some, but not all, patients' responses differed from normal subjects but responses also differed by age and sex. ROC values were all weak, i.e. < 0.8. No good cut-off points differentiated controls from patients. Thus, although the bucket test is useful for describing spatial deficits in patients this test is not useful for screening people for possible vestibular impairments.
    Acta oto-laryngologica 06/2012; 132(8):850-4. DOI:10.3109/00016489.2012.668710 · 0.99 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The study sought to provide norms for a simple test of visual perception of verticality (subjective visual vertical). The study was designed as a cohort study with a balanced design. The setting was the Rehabilitation Department of a University Hospital. Twenty-two healthy adults, of 23-58 years, 11 men (three left handed) and 11 women (three left handed) were enrolled. A luminous bar was displayed on a PC screen, and rotated in steps of 0.4° until the participant perceived it as vertical. A positive sign was attributed to a clockwise rotation of the bar. The detection threshold was set at the angle corresponding to a perceived vertical, which the participant then selected out of three subsequent alternatives (each at +0.4 or -0.4°). The participant's position (sitting vs. standing) and the preset angle of presentation (clockwise vs. counterclockwise) were balanced across sex. The constant or deviation error (dE, in degrees) and the absolute errors (aE, in degrees) were computed. An analysis of variance model tested the dependence of dE on sex, posture, age, handedness, and the preset angle. Both dE and aE were unrelated to sex, posture, handedness, and the preset angle, but were dependent on age (junior, ≤43 years; senior, >43 years). The mean dE was -0.14 ± 0.60 in the junior and 0.42 ± 0.64 in the senior group, respectively. The minimal real difference of the dE was 0.75 and 0.25 in the junior and the senior group, respectively. The overall median aE was 0.4 (5th-95th percentile 0-1.2) in the junior and 0.8 (0.4-1.46) in the senior group, respectively. The whole test took no longer than 15 min in healthy participants, and 25 min in stroke patients. The test was applied to three subacute stroke patients with left hemiparesis, of whom two showed left spatial hemineglect. All three patients presented with a significant clockwise dE. This simple test appears to be valid for the routine assessment of spatial disorders in neurological impairments.
    International journal of rehabilitation research. Internationale Zeitschrift fur Rehabilitationsforschung. Revue internationale de recherches de readaptation 09/2011; 34(4):307-15. DOI:10.1097/MRR.0b013e32834c45bc · 1.14 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The subjective visual vertical (SVV, the visual estimation of gravitational direction) is commonly considered as an indicator of the sense of orientation. The present study examined the impact of two methodological factors (the angle size of the stimulus and the participant's gender) on deviations of the SVV caused by head tilt. Forty healthy participants (20 men and 20 women) were asked to make visual vertical adjustments of a light bar with their head held vertically or roll-tilted by 30° to the left or to the right. Line angle sizes of 0.95° and 18.92° were presented. The SVV tended to move in the direction of head tilt in women but away from the direction of head tilt in men. Moreover, the head-tilt effect was also modulated by the stimulus' angle size. The large angle size led to deviations in the direction of head-tilt, whereas the small angle size had the opposite effect. Our results showed that gender and line angle size have an impact on the evaluation of the SVV. These findings must be taken into account in the growing body of research that uses the SVV paradigm in disease settings. Moreover, this methodological issue may explain (at least in part) the discrepancies found in the literature on the head-tilt effect.
    BMC Neuroscience 03/2012; 13:28. DOI:10.1186/1471-2202-13-28 · 2.85 Impact Factor