title: Drawing ability in typical and atypical development; colour cues and the effect of oblique lines.
abstract: BACKGROUND
  Individuals with Williams syndrome (WS) have poor drawing ability. Here, we investigated whether colour could be used as a facilitation cue during a drawing task.
  
  
  METHODS
  Participants with WS and non-verbal ability matched typically developing (TD) children were shown line figures presented on a 3 by 3 dot matrix, and asked to replicate the figures by drawing on an empty dot matrix. The dots of the matrix were either all black (control condition), or nine different coloured dots (colour condition). In a third condition, which also used coloured dots, participants were additionally asked to verbalise the colours of the dots prior to replicating the line drawings (colour-verbal condition).
  
  
  RESULTS
  Performance was stronger in both WS and TD groups on the two coloured conditions, compared with the control condition. However, the facilitation effect of colour was significantly weaker in the WS group than in the TD group. Replication of oblique line segments was less successful than replication of non-oblique line segments for both groups; this effect was reduced by colour facilitation in the TD group only. Verbalising the colours had no additional impact on performance in either group.
  
  
  CONCLUSIONS
  We suggest that colour acted as a cue to individuate the dots, thus enabling participants to better ascertain the spatial relationships between the parts of each figure, to determine the start and end points of component lines, and to determine the correspondence between the model and their replication. The reduced facilitation in the WS group is discussed in relation to the effect of oblique versus non-oblique lines, the use of atypical drawing strategies, and reduced attention to the model when drawing the replication.
authors.affiliation: Department of Psychology and Human Development, Institute of Education, University of London, London, UK.
authors.forename: E K
authors.initials: EK
authors.lastname: Farran
authors.forename: G F
authors.initials: GF
authors.lastname: Dodd
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003118:Color Perception / Q000502:physiology*; D003463:Cues; D006801:Humans; D010364:Pattern Recognition, Visual / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D018980:Williams Syndrome / Q000503:physiopathology*; D055815:Young Adult
keywords: Williams syndrome; colour; drawing; oblique lines; visuo-spatial cognition