Visual Illusions

Main Researcher: Ana Pires

Team: Alejandro Maiche, Ana Pires, Anna Vilaró, Juan Ignacio Sanguinetti, Juan Ramón Barrada.

Based on previous research (Jancke et al. 2004; Maiche et al., 2007; Pires, 2010) we propose to study in detail the phenomenon of spatial facilitation in order to understand human perception of motion. This facilitation occurs whenever there is motion near the location of a certain object. Thus, it is necessary to obtain psychophysical data to understand how this mechanism works by detecting the spatial facilitation threshold through psychometric curves and reaction time measures. Therefore, we intend to investigate the influence of different speeds on apparent motion (horizontal) and verify whether there is a correspondence between the phenomenon of spatial facilitation proposed by Maiche et al. (2007) and the psychophysical measures obtained in humans. It is also relevant to discern its effect along the horizontal dimension which comprises a large time window and checking its enhancement or disappearance. Additionally, the influence of the time window is relevant to establish a general mechanism of the effect of this facilitation, and for this we will carry out several experiments that manipulate the time duration between motion stimuli. Another important issue will be distinguishing this effect when motion is central-peripheral (away from the fovea), because there is less pre-activation of neurons. Our results will provide empirical evidence about the shape and size of the space-time window, as well as about the influence of speed and direction of motion on the spatial facilitation effect caused by motion.

Presentations: 

10/06/2011 at Facultad de Medicina-UdelaR. Invited speaker in Seminarios de Fisiología. For acces to the presentation, click Aqui

07/07/2011 en el 4th Iberian Congress of Perception, Mallorca-Spain. Abstract of the talk. For acces to the presentation, click Aqui