Hemispatial asymmetries in judgment of stimulus size

Recent research has demonstrated a leftward bias in judgments of size. In the present experiments, hemispatial size bias was measured through simultaneous presentation of a circle and an ellipse varying in horizontal or vertical extent. A consistent leftward bias of horizontal size judgments (but not vertical) was obtained; at the point of subjective equality, the width of the objects that were presented in left hemispace was smaller than the width of the objects that were presented in right hemispace. These data suggest that the horizontal extent of stimuli appear larger in left hemispace than in right hemispace. Results also indicated that symmetrical stimulus presentation, with respect to the vertical meridian, is required for the bias to emerge. Furthermore, increasing or decreasing stimulus eccentricity weakened the effect. Attenuation of this bias upon the manipulation of parameters indicates that this phenomenon is context specific and is affected by similar parameters that are known to influence the magnitude of error in pseudoneglect.

[1]  Mark Mapstone,et al.  Cerebral hemispheric specialization for spatial attention: spatial distribution of search-related eye fixations in the absence of neglect , 2003, Neuropsychologia.

[2]  David T Wilkinson,et al.  Stimulus symmetry affects the bisection of figures but not lines: evidence from event-related fMRI , 2003, NeuroImage.

[3]  M. McCourt,et al.  Pseudoneglect: a review and meta-analysis of performance factors in line bisection tasks , 2000, Neuropsychologia.

[4]  J. Marshall,et al.  Individual variation in line bisection: A study of normal subjects with application to the interpretation of visual neglect , 1990, Neuropsychologia.

[5]  E. Renzi,et al.  Attentional Shift Towards the Rightmost Stimuli in Patients with Left Visual Neglect , 1989, Cortex.

[6]  Mark E McCourt,et al.  Stimulus modulation of pseudoneglect: influence of line geometry , 2000, Neuropsychologia.

[7]  Jerre Levy,et al.  Perceptual asymmetries for free viewing of several types of chimeric stimuli , 1991, Brain and Cognition.

[8]  A. Milner,et al.  To halve and to halve not: An analysis of line bisection judgements in normal subjects , 1992, Neuropsychologia.

[9]  K. Heilman,et al.  Right hemisphere dominance for attention , 1980, Neurology.

[10]  A. Milner,et al.  Line bisection errors in visual neglect: Misguided action or size distortion? , 1993, Neuropsychologia.

[11]  M. Nicholls,et al.  The nature and contribution of space- and object-based attentional biases to free-viewing perceptual asymmetries , 2005, Experimental Brain Research.

[12]  Mark E. McCourt,et al.  Visuospatial attention in line bisection: stimulusmodulation of pseudoneglect , 1999, Neuropsychologia.

[13]  Peter W Halligan,et al.  The effects of stimulus symmetry on landmark judgments in left and right visual fields , 2002, Neuropsychologia.

[14]  M. Kinsbourne.  Mechanisms of Unilateral Neglect , 1987 .

[15]  M. McCourt,et al.  Cognitive and perceptual influences on visual line bisection: Psychophysical and chronometric analyses of pseudoneglect , 1997, Neuropsychologia.

[16]  I. Mcmanus,et al.  Objects look different sizes in the right and left eyes. , 2004, Laterality.

[17]  R. Menzel,et al.  Symmetry perception in an insect , 1996, Nature.

[18]  P. Reuter-Lorenz,et al.  Vertical orienting control: evidence for attentional bias and "neglect" in the intact brain. , 1996, Journal of experimental psychology. General.

[19]  B. Anderson,et al.  A mathematical model of line bisection behaviour in neglect. , 1996, Brain : a journal of neurology.

[20]  G Gainotti,et al.  The relationships between disorders of visual perception and unilateral spatial neglect. , 1971, Neuropsychologia.

[21]  R. Thornhill,et al.  Bilateral Symmetry and Sexual Selection: A Meta‐Analysis , 1998, The American Naturalist.

[22]  P Wenderoth,et al.  Detection of Bilateral Symmetry in Complex Biological Images , 2000, Perception.

[23]  P J Locher,et al.  Effects of Element Type and Spatial Grouping on Symmetry Detection , 1993, Perception.

[24]  S. Tipper,et al.  Object-centered not scene-based visual neglect. , 1996, Journal of experimental psychology. Human perception and performance.

[25]  M. Jeannerod.  Neurophysiological and neuropsychological aspects of spatial neglect. , 1987 .

[26]  Daniel C. Javitt,et al.  Right hemisphere control of visuospatial attention: line-bisection judgments evaluated with high-density electrical mapping and source analysis☆ , 2003, NeuroImage.

[27]  J. Marshall,et al.  Right-sided cueing can ameliorate left neglect , 1994 .

[28]  K M Heilman,et al.  Peripersonal and vertical neglect. , 1990, Brain : a journal of neurology.

[29]  K. Heilman,et al.  Pseudoneglect: Effects of hemispace on a tactile line bisection task , 1980, Neuropsychologia.

[30]  J. Driver,et al.  Can Visual Neglect Operate in Object-centred Co-ordinates? An Affirmative Single-case Study , 1991 .

[31]  M. Nicholls,et al.  Free-viewing perceptual asymmetries for the judgement of brightness, numerosity and size , 1999, Neuropsychologia.

[32]  D. LaBerge,et al.  Theory of attentional operations in shape identification. , 1989 .

[33]  M. Nicholls,et al.  An investigation of the relationship between free-viewing perceptual asymmetries for vertical and horizontal stimuli. , 2004, Brain research. Cognitive brain research.

[34]  J. Mattingley,et al.  Can task specific perceptual bias be distinguished from unilateral neglect? , 1994, Neuropsychologia.

[35]  H. Barlow,et al.  The versatility and absolute efficiency of detecting mirror symmetry in random dot displays , 1979, Vision Research.

[36]  M. Kinsbourne.  The cerebral basis of lateral asymmetries in attention. , 1970, Acta psychologica.

[37]  Kenneth M. Heilman,et al.  Hemispace and Hemispatial Neglect , 1987 .

[38]  M. Carrasco,et al.  The eccentricity effect: Target eccentricity affects performance on conjunction searches , 1995, Perception & psychophysics.

[39]  M. Nicholls,et al.  Can Free-Viewing Perceptual Asymmetries be Explained by Scanning, Pre-Motor or Attentional Biases? , 2002, Cortex.

[40]  S. Ferber,et al.  Size perception in hemianopia and neglect. , 2001, Brain : a journal of neurology.

[41]  P Wenderoth,et al.  The Salience of Vertical Symmetry , 1994, Perception.

[42]  A. Kirk,et al.  A Normal Bias Toward a Pictorially Defined Top in Line Bisection , 1996, Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques.

[43]  Mark E. McCourt,et al.  Asymmetries of Visuospatial Attention are Modulated by Viewing Distance and Visual Field Elevation: Pseudoneglect in Peripersonal and Extrapersonal Space , 2000, Cortex.

[44]  J. Wolfe,et al.  Why are there eccentricity effects in visual search? Visual and attentional hypotheses , 1998, Perception & psychophysics.

[45]  M. Nicholls,et al.  The effect of strategy on pseudoneglect for luminance judgements. , 2005, Brain research. Cognitive brain research.

[46]  R. B. Post,et al.  Contributions of object- and space-based mechanisms to line bisection errors , 2001, Neuropsychologia.

[47]  K M Heilman,et al.  Hemispace-visual field interactions in visual extinction. , 1987, Journal of neurology, neurosurgery, and psychiatry.

[48]  K. Luh.  Line bisection and perceptual asymmetries in normal individuals: What you see is not what you get. , 1995 .

[49]  A. Milner,et al.  Distortion of size perception in visuospatial neglect , 1995, Current Biology.

[50]  Mark E. McCourt,et al.  The Influence of Unimanual Response on Pseudoneglect Magnitude , 2001, Brain and Cognition.

[51]  J. Marshall,et al.  Hemispheric activation vs spatio-motor cueing in visual neglect: A case study , 1991, Neuropsychologia.

[52]  M. P. Bryden,et al.  Different Dimensions of Hand Preference That Relate to Skilled and Unskilled Activities , 1989, Cortex.