What Do We Really See? Memory Provides Miraculous Detail, Not The Eye
Though most of us assume we can see the miraculous detail of the world around us, our eyes and brain are actually deceiving us. According to recent findings published in the Journal of Experimental Psychology, researchers have found that the brain works to fool the human body into believing that we see in sharp detail by calling on the memory of past visual experiences.
"In our study we are dealing with the question of why we believe that we see the world uniformly detailed," said Dr. Arvid Herwig from the Neuro-Cognitive Psychology research group of the Faculty of Psychology and Sports Science. The group is also affiliated to the Cluster of Excellence Cognitive Interaction Technology (CITEC) of Bielefeld University and is led by Professor Dr. Werner X. Schneider, in a news release.
Researchers remind us that only the fovea, otherwise known as the central area of the retina, can actually process objects precisely. In other words, this would mean that we could only see a small area of our environment in sharp detail that's about the equivalent of a thumbnail at the end of an outstretched arm.
However, all visual impressions that occur outside the fovea on the retina become progressively coarse; that's when are memory kicks in-helping us to "believe" that we do, indeed, see large parts of the environment in sharp detail. Unfortunately, in reality, we really don't.
Researchers took an in-depth look at the idea through a series of experiments that approach how people learn through countless eye movements over a lifetime to connect the coarse impressions of objects outside the fovea to detailed visual impressions after the eye has moved to the object of interest.
Researchers used eye-tracking experiments to test the approach, with the technique that harnesses a specific camera that can record 1,000 images per second. Scientists have recorded fast ballistic eye movements.
Though most of the participants did not realise it, certain objects were changed during eye movement. The aim was that the test persons learn new connections between visual stimuli from inside and outside the fovea, in other words from detailed and coarse impressions. Afterwards, the participants were asked to judge visual characteristics of objects outside the area of the fovea
Findings revealed that the connection between a coarse and detailed visual impression occurred after just a few minutes. The coarse visual impressions became similar to the newly learnt detailed visual impressions.
"The experiments show that our perception depends in large measure on stored visual experiences in our memory," says Arvid Herwig. According to Herwig and Schneider, these experiences serve to predict the effect of future actions ("What would the world look like after a further eye movement"). In other words: "We do not see the actual world, but our predictions."