Format

Send to

Choose Destination
Perception. 1998;27(4):393-402.

Reference repulsion when judging the direction of visual motion.

Author information

1
Department of Neurology, University of Tübingen, Germany. rauber@uni-tuebingen.de; treue@uni-tuebingen.de

Abstract

While humans are very reliable (i.e. give highly reproducible answers) when repeatedly judging the direction of a moving random-dot pattern (RDP) we find that their accuracy (i.e. the direction they so reliably report) shows systematic errors. To quantify these errors, we presented a complete set of closely spaced directions and mapped the directional misjudgments by asking subjects to compare the perceived direction of a moving RDP with the direction of a test line. The results show misjudgments of up to 9 degrees, which are best accounted for by a tendency of the subjects to overestimate the angle between the observed motion and an internal reference direction. A control experiment in which subjects had to judge the spatial distance between a point and a line demonstrates that these misjudgments are not confined to motion stimuli but rather seem to reflect a general tendency to overestimate the distance between a stimulus and a reference when they are close to each other.

PMID:
9797918
DOI:
10.1068/p270393
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Atypon
Loading ...
Support Center