When each dot, of a sequence of dots horizontally aligned, lies within a circle, and the circles are not horizontally aligned, the dots are illusory perceived misaligned (Giovanelli, 1966, Rivista di Psicologia, 60, 327-336). Previous studies have suggested that the illusion of Giovanelli is based on the influence of the frame of reference. In the present research, we tested the role of the factor directionality on the illusory misalignment. A sequence of disaligned circles was adopted to induce the illusion. The directionality (the inclination of the sequence of circles) was .5 degrees. The adjustment method was adopted: participants varied the position of each dot, from the left to the right of the sequence, until an aligned sequence of dots was obtained. The results indicate that the directionality of the sequence of inductive stimuli increases the horizontally misalignment. We conclude that the frame of reference but also the influence of directionality is crucial to provide a comprehensive account of the illusion. The model of orientation maps (Kenet, Bibitchkov, Tsodyks, Grinvald & Arieli, 2003, Nature, 425, 954-956) is discussed.
The role of directionality in Giovanelli's illusion / Giovanelli G.; Sinico M.. - In: PERCEPTION. - ISSN 0301-0066. - STAMPA. - 34:(2005), pp. 107-108. (Intervento presentato al convegno European Conference on Visual Perception tenutosi a A Coruna - Spagna nel 22-26 agosto 2005).
The role of directionality in Giovanelli's illusion
GIOVANELLI, GIULIANA;SINICO, MICHELE
2005
Abstract
When each dot, of a sequence of dots horizontally aligned, lies within a circle, and the circles are not horizontally aligned, the dots are illusory perceived misaligned (Giovanelli, 1966, Rivista di Psicologia, 60, 327-336). Previous studies have suggested that the illusion of Giovanelli is based on the influence of the frame of reference. In the present research, we tested the role of the factor directionality on the illusory misalignment. A sequence of disaligned circles was adopted to induce the illusion. The directionality (the inclination of the sequence of circles) was .5 degrees. The adjustment method was adopted: participants varied the position of each dot, from the left to the right of the sequence, until an aligned sequence of dots was obtained. The results indicate that the directionality of the sequence of inductive stimuli increases the horizontally misalignment. We conclude that the frame of reference but also the influence of directionality is crucial to provide a comprehensive account of the illusion. The model of orientation maps (Kenet, Bibitchkov, Tsodyks, Grinvald & Arieli, 2003, Nature, 425, 954-956) is discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
