Distance Perception Across Surfaces With Three Different Types of Curvature

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Distance Perception Across Surfaces With Three
Different Types of Curvature

• Allison Adams, Nicholas Rudd, and Cary Feria
• Morehead State University
• Supported by MSU Research and CreativeProductions
  Grant 10-225230

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Background Continued

• Less distance is perceived if a surface contains
  differently textured regions than uniformly
  textured surfaces. (Feria, Braunstein, Anderson,
  2003)

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Theoretical Background

• Previous research has found that distance
  perception can be affected by certain
  characteristics of curved surfaces (Feria,
  Braunstein, Anderson, 2004)
• Our visual systems break down shapes into parts
  using a rule of defining part boundaries
  (Hoffman, Richards, 1984)
• Negative Minima of Curvature

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Question

• Is the perception of distance reduced because of
  a curved surface or object based parts?

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Method

• Participants 15 Morehead State University
  students
• Normal or corrected-to-normal visual acuity
• Procedure Participants were presented with a
  computer image with a 3 D surface in a random
  order (non-constant, constant, and non-zero
  curvature)
• Curved surfaces were either concaved or convex
• Task To manipulate the distances between three
  dots

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Definition of Surfaces

• Bump- Non-constant
• Cylinder-Constant
• Plane-Zero Curvature
• Height of Cylinders and Bumps 4.3 cm, -4.3 cm

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Method Continued

• Design
• Within-Subjects
• IV1 type of surface (plane, convex bump,
  convex cylinder, concave bump, and concave
  cylinder)
• IV2 distance between bottom dots
• Distance between dots 19.5 cm, 21.7 cm
• IV3 side of the monitor on which the response
  dot is located (top dot)
• DV judged distance between the bottom dots

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Sample of Stimulus
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Results
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Results

• There were no significant differences found
  between the perceived distance on a plane and
  curved surfaces
• F (3.120 , 43.683) 2.08, pgt.05 (df Greenhouse-
  Geisser adjusted)

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Discussion

• No significant differences were found between the
  distance judged on a plane and on curved surfaces
• In this study, the cylinder and the bump were
  matched in amplitude (unlike the previous study
  where the bump had a lot more curvature)
• Perceived distance judged across a small amount
  of curvature are not shorter than planar surfaces