j *@ - Sociedade Brasileira de Psicologia

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FIGURE 5 FIGURE 6
running a second experiment in which the subject views two targets defming either a
frontal interval or a depth interval and then, with eyes closed , proceeds toward the
targets and attempts to plant his foot at the location of one target and then a few
stepts later at the location of the second, each tim' e saying 'Yere' to indicate his
response. With just two subjects run so far, Jo'sé has infonned me that subjects seem to
be quite accurate in indicating b0th frontal and depth i .ntervals.
How might we reconcile the results of the two knds of task? First, we tak . e
it as a given that visual perception of near space is distorted even under full cue conditions.
.Folowing Thomson (1983), we assume that the subject establishes an internal
representation of the target and the path to it based on what the subject perceived
when ltis eyes were open. As the subject moves through space with ltis eyes cloRd, this
internal representation is ùpdated or transformed as the subject walks over the pound.
What is the nature of this transformation? Prompted by the thinking of Rieser, Guth ,
and Hil (1986) and Shepard (1984), we argue that the internal representation
transforms much in the same way that visual space transforms as we walk through it .
When we Pove through spacv with our eyes open, depth intervals that are perceptualy
underçstimated in the dijtance incre%e as we approach them . tâkewise, we caù argue