Optical Illusions In Vertebrates

Abstract

SOME OPTICAL ILLUSION PATTERNS WERE PRESENTED TO CRUCIAN CARPS, DOMESTIC CHICKS, MISTLE THRUSH, STARLINGS, AMANDAVA-FINCHES, AND GUINEA PIGS. THE ANIMALS HAD TO CHOOSE 1 OF 2 PATTERNS AND WERE POSITIVELY REINFORCED; THEN THEY WERE TESTED WITH 2 OPTICAL ILLUSION PATTERNS WHICH BOTH CARRIED FOOD REWARD. SUSCEPTIBLE TO THE ZOLLNER ILLUSION WERE 4 CRUCIAN CARPS, 1 CHICK, 2 AMANDAVATS, 2 STARLINGS, 1 MISTLE THRUSH, AND 2 GUINEA PIGS. THE EBBINGHAUS ILLUSTRATION WAS FOUND IN 5 CRUCIAN CARPS, 2 AMANDAVATS, 1 STARLING, AND 4 GUINEA PIGS. THE ENRENSTEIN ILLUSION WAS EFFECTIVE IN 7 OUT OF 8 CRUCIAN CARPS, THE STARLING, AND THE GUINEA PIG TESTED. RESULTS ARE COMPARED WITH VARIOUS THEORIES ABOUT OPTICAL ILLUSIONS; THE MOST RELEVANT APPEAR TO BE THE EYE MOVEMENT AND THE ATTENTION THEORIES. (ENGLISH SUMMARY) (113 REF.) (PsycINFO Database Record (c) 2005 APA, all rights reserved).