The purpose of our visual system is to see and recognize objects in order to help us interact with the objects around us. However, because our perception of the visual world is not always accurate, it also introduces us to various biases and misconceptions. For example; stereotyping. Our vision is trying to fit the information that we see into a known recognizable category so that we know how to interact with those objects or people. Because the primary purpose of the visual system is to recognize objects, we can be biased towards interpreting something ambiguous as something we know.
Some of the common misconceptions about how our vision operates include, firstly, we believe that the visual world around us is an accurate projection of how those objects truly are. This misconception also suggests that - vision is an automatic and effortless process, and that vision is always accurate. However, is this true? Take for example the Ponzo illusion study (He, Mo, Wang, & Fang, 2015) where two identical objects with the exact same size when placed at different visual depths appear as though the size of the objects are different. Non-parallel lines are placed beside two objects, which create a visual illusion of distance – so that the lower object is perceived as being closer to the viewer and is perceived as larger. Although the study didn’t give us a broad range of perspective due to the limited number of 9 participants and all of them between age 18 to 28, the study did give us enough evidence to suggest that there are gaps in how our vision perceives the real world. And this illusion has been robustly replicated in many other studies.
Second misconception – That we remember everything accurately that we see. Let’s take for example the Elizabeth Loftis experiment (MCLeod, 2014) where 45 students were shown 7 films of traffic accidents ranging from 5 to 30 seconds. After they have watched the film when asked what they saw, most described the incident as though they witnessed the event in-person. When asked specific questions like “what was the speed of the car?” Or “at what speed did the two cars “hit” each other,” students responded with a specific number while that information was not present in the film. Students responses were biased based on the critical verb used in the question. The word “hit” changed the perception of how they interpreted what they saw. In this experiment, although the experiment was confined to students and emphasizes verb impact on memory retrieval, it still gives us enough evidence to consider gaps in the detailed accuracy of our visual perception, particularly if we are trying to relay something that we saw in the past.
Thirdly, a misconception about the visual systems includes that everything around us is a rich and continuous environment, part of some objects/things that can be readily perceived. A study by Resink, Regan and Clark, (Rensink, O'Regan, & Clark, 1997) showed that when as an observer we look at things around us, we feel like we see all the details and we can recall any details accurately; however, there are gaps in the way our mind encodes what we see. If the scene we were observing was modified to include blocks of blank fields between alternating displays, it would be extremely difficult to identify those changes. Again, we interpret ambiguous information as part of a recognizable whole. The study also suggests that, when a verbal cue is provided, identification of the changes become easier and faster.
Although the data on all these studies are minimal and didn’t consider the wide range of participants and scenarios, it does outline evidence that there clearly are various misconceptions to how what we see and how our mind perceives what we see are actually related, and to how the mind changes what we “see” to fit our understandings of our world.
I would like to conclude by saying - as an observer we can never really form a complete detailed representation of events we see around unless we pay attention (Rensink et al., 1997) and backup the visual memory with verbal cues. Our perception of the world is not only based on what we see and how our brain translates what we see but also our stored memory and how our brain uses the stored memory to translate the new visual input it receives. Again, we have strong biases to “see” things that we can label and understand.
He, D., Mo, C., Wang, Y., & Fang, F. (2015). Position shifts of fMRI-based population receptive fields in human visual cortex induced by Ponzo illusion. Experimental Brain Research, 233(12), 3535-3541. doi:10.1007/s00221-015-4425-3
Rensink, R. A., O'Regan, J. K., & Clark, J. J. (1997). To See or not to See: The Need for Attention to Perceive Changes in Scenes. Psychological Science, 8(5), 368-373. doi:10.1111/j.1467-9280.1997.tb00427.x