TR available: Representation of similarity in 3D ...

[Edelman Shimon]

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Representation of similarity in 3D object discrimination

Shimon Edelman

\begin{abstract}

  How does the brain represent visual objects? In simple perceptual
  generalization  tasks, the human visual system performs as if
  it represents the stimuli in a low-dimensional metric psychological
  space \cite{Shepard87}. In theories of 3D shape recognition, the
  role of feature-space representations (as opposed to structural
  \cite{Biederman87} or pictorial \cite{Ullman89} descriptions) has
  been for a long time a major point of contention. If shapes are
  indeed represented as points in a feature space, patterns of
  perceived similarity among different objects must reflect the
  structure of this space. The feature space hypothesis can then be
  tested by presenting subjects with complex parameterized 3D shapes,
  and by relating the similarities among subjective representations,
  as revealed in the response data by multidimensional scaling
  \cite{Shepard80}, to the objective parameterization of the stimuli.
  The results of four such tests, reported below, support the notion
  that discrimination among 3D objects may rely on a low-dimensional
  feature space representation, and suggest that this space may be
  spanned by explicitly encoded class prototypes.  

\end{abstract}