Seeing is believing, or is it?March 26th, 2008 - 3:16 pm ICT by admin
New York, March 26 (IANS) People do see objects but it is the assumptions they make about them that colour their perceptions. A study has thrown up insights into how the brain and the eye work together to interpret daily sights.
The study sought to discover how people visually interpret a changing or uncertain environment in the absence of common visual assumptions.
The study also suggests that when in doubt, people are biased towards believing that they were looking directly at what they have seen.
Prior studies have confirmed that people’s familiarity with the world around them allows them to make credible assumptions about what they see.
Eight subjects participated in two experiments to identify the location of a jumping target (a circular green cursor). In the first session, the target jumped to different locations within five concentric circles (arranged around a fixation point) every 250 milliseconds.
The subjects had to position a mouse cursor at the location where the target had been at the moment of a flash. The second session mimicked the first except a tone replaced the flash. Each session continued until subjects made 250 responses.
The authors found that participants clearly preferred to select target positions nearer to where their eyes were looking. This finding held true whether a tone or a flash indicated the moment of interest.
“Without making assumptions about our environment, our possibilities for interpreting visual stimulation would be quite limited,” explained EM Brenner of Vrije Universiteit, Amsterdam, who led the research team.
The study appeared in the Journal of Vision.
Tags: absence, assumptions, brain, brenner, concentric circles, eye work, familiarity, fixation, fixation point, insights, milliseconds, mouse cursor, participants, perceptions, possibilities, second session, target positions, visual stimulation, vrije universiteit amsterdam, when in doubt