The effects of cross-sensory attentional demand on subitizing and on mapping number onto space

Various aspects of numerosity judgments, especially subitizing and the mapping of number onto space, depend strongly on attentional resources. Here we use a dual-task paradigm to investigate the effects of cross-sensory attentional demands on visual subitizing and spatial mapping. The results show that subitizing is strongly dependent on attentional resources, far more so than is estimation of higher numerosities. But unlike many other sensory tasks, visual subitizing is equally affected by concurrent attentionally demanding auditory and tactile tasks as it is by visual tasks, suggesting that subitizing may be amodal. Mapping number onto space was also strongly affected by attention, but only when the dual-task was in the visual modality. The non-linearities in numberline mapping under attentional load are well explained by a Bayesian model of central tendency.

[1]  H. Hollingworth.  The Central Tendency of Judgment , 1910 .

[2]  Christian N. L. Olivers,et al.  Subitizing requires attention , 2008 .

[3]  Rochel Gelman,et al.  Variability signatures distinguish verbal from nonverbal counting for both large and small numbers , 2001, Psychonomic bulletin & review.

[4]  Julie L. Booth,et al.  Development of numerical estimation in young children. , 2004, Child development.

[5]  D H Brainard,et al.  The Psychophysics Toolbox. , 1997, Spatial vision.

[6]  A. Bonnel,et al.  Divided attention between simultaneous auditory and visual signals , 1998, Perception & psychophysics.

[7]  David C. Geary,et al.  Development of Number Line Representations in Children With Mathematical Learning Disability , 2008, Developmental neuropsychology.

[8]  Michael N. Shadlen,et al.  Temporal context calibrates interval timing , 2010, Nature Neuroscience.

[9]  Andrew Simpson,et al.  Subitizing in Tactile Perception , 2006, Psychological science.

[10]  D. Melcher,et al.  Subitizing reflects visuo-spatial object individuation capacity , 2011, Cognition.

[11]  F. Campbell,et al.  The Magic Number 4 ± 0: A New Look at Visual Numerosity Judgements , 1976, Perception.

[12]  D. Burr,et al.  Optimal Encoding of Interval Timing in Expert Percussionists , 2011, The Journal of Neuroscience.

[13]  Daniel C. Hyde,et al.  Spatial Attention Determines the Nature of Nonverbal Number Representation , 2011, Journal of Cognitive Neuroscience.

[14]  Barbara Tillmann,et al.  Discontinuity in the enumeration of sequentially presented auditory and visual stimuli , 2008, Cognition.

[15]  Hilary C Barth,et al.  The development of numerical estimation: evidence against a representational shift. , 2011, Developmental science.

[16]  Brian Butterworth,et al.  Are Subitizing and Counting Implemented as Separate or Functionally Overlapping Processes? , 2002, NeuroImage.

[17]  David C Burr,et al.  Adaptation affects both high and low (subitized) numbers under conditions of high attentional load. , 2011, Seeing and perceiving.

[18]  F. Gregory Ashby,et al.  Subitizing: Magical numbers or mere superstition? , 1992, Psychological research.

[19]  G. Mandler,et al.  Subitizing: an analysis of its component processes. , 1982, Journal of experimental psychology. General.

[20]  H. Pashler.  Attentional Limitations in Doing Two Tasks at the Same Time , 1992 .

[21]  H. Pashler.  Dual-task interference in simple tasks: data and theory. , 1994, Psychological bulletin.

[22]  J. Ross.  Visual Discrimination of Number without Counting , 2003, Perception.

[23]  D. Somers,et al.  Functional MRI reveals spatially specific attentional modulation in human primary visual cortex. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[24]  P. H. Lindsay,et al.  Quantification of shared capacity processing in auditory and visual discrimination. , 1967, Acta psychologica.

[25]  L. Jäncke,et al.  Attention Modulates the Blood Oxygen Level Dependent Response in the Primary Visual Cortex measured with Functional Magnetic Resonance Imaging , 1999, Naturwissenschaften.

[26]  Vision Research , 1961, Nature.

[27]  Brian Butterworth,et al.  Mapping numerical magnitudes along the right lines: differentiating between scale and bias. , 2011, Journal of experimental psychology. General.

[28]  B. Repp.  Perceiving the numerosity of rapidly occurring auditory events in metrical and nonmetrical contexts , 2007, Perception & psychophysics.

[29]  K L Shapiro,et al.  Temporary suppression of visual processing in an RSVP task: an attentional blink? . , 1992, Journal of experimental psychology. Human perception and performance.

[30]  David C. Burr,et al.  Linear mapping of numbers onto space requires attention , 2012, Cognition.

[31]  R. Siegler,et al.  The Development of Numerical Estimation , 2003, Psychological science.

[32]  E. L. Kaufman,et al.  The discrimination of visual number. , 1949, The American journal of psychology.

[33]  David Alais,et al.  Separate attentional resources for vision and audition , 2006, Proceedings of the Royal Society B: Biological Sciences.

[34]  David C Burr,et al.  Subitizing but not estimation of numerosity requires attentional resources. , 2010, Journal of vision.

[35]  Julie L. Booth,et al.  Developmental and individual differences in pure numerical estimation. , 2006, Developmental psychology.

[36]  C. Gilbert,et al.  Attention and primary visual cortex. , 1999, Proceedings of the National Academy of Sciences of the United States of America.

[37]  D. Burr,et al.  Vision and Audition Do Not Share Attentional Resources in Sustained Tasks , 2011, Front. Psychology.

[38]  Astrid M L Kappers,et al.  One, two, three, many - subitizing in active touch. , 2009, Acta psychologica.

[39]  Mary K. Hoard,et al.  Cognitive mechanisms underlying achievement deficits in children with mathematical learning disability. , 2007, Child development.

[40]  Brian Butterworth,et al.  The Mathematical Brain , 1999 .

[41]  Bahador Bahrami,et al.  Modulating Attentional Load Affects Numerosity Estimation: Evidence against a Pre-Attentive Subitizing Mechanism , 2008, PloS one.

[42]  D. Burr,et al.  Saccades compress space, time and number , 2010, Trends in Cognitive Sciences.

[43]  C. Gallistel,et al.  Nonverbal Counting in Humans: The Psychophysics of Number Representation , 1999 .

[44]  Henry Railo,et al.  The role of attention in subitizing , 2008, Cognition.

[45]  Z. Pylyshyn,et al.  Why are small and large numbers enumerated differently? A limited-capacity preattentive stage in vision. , 1994, Psychological review.

[46]  A. Henik,et al.  A disassociation between physical and mental number bisection in developmental dyscalculia , 2010, Neuropsychologia.

[47]  C. Gallistel,et al.  Preverbal and verbal counting and computation , 1992, Cognition.

[48]  J Driver,et al.  Cross-modal selective attention: On the difficulty of ignoring sounds at the locus of visual attention , 2000, Perception & psychophysics.

[49]  Claus Bundesen,et al.  Seeing or hearing? Perceptual independence, modality confusions, and crossmodal congruity effects with focused and divided attention , 2003, Perception & psychophysics.

[50]  Brian Butterworth,et al.  Exact and Approximate Judgements of Visual and Auditory Numerosity: an Fmri Study , 2006 .

[51]  M. Crommelinck,et al.  When audition alters vision: an event-related potential study of the cross-modal interactions between faces and voices , 2004, Neuroscience Letters.

[52]  E Tulving,et al.  Identification of simultaneously presented simple visual and auditory stimuli. , 1967, Acta psychologica.

[53]  S. Dehaene,et al.  The Number Sense: How the Mind Creates Mathematics. , 1998 .

[54]  D. Burr,et al.  A Visual Sense of Number , 2007, Current Biology.

[55]  Scott T. Grafton,et al.  Neural Evidence Linking Visual Object Enumeration and Attention , 1999, Journal of Cognitive Neuroscience.

[56]  Pierre Pica,et al.  Log or Linear? Distinct Intuitions of the Number Scale in Western and Amazonian Indigene Cultures , 2008, Science.

[57]  Notger G. Müller,et al.  Competing Neural Responses for Auditory and Visual Decisions , 2007, PloS one.

[58]  Z W Pylyshyn,et al.  Tracking multiple independent targets: evidence for a parallel tracking mechanism. , 1988, Spatial vision.