Perceptual Set

“We perceive the world not as it is, but as it is useful for us to perceive it”

I think we can all agree that the way you or I view the world is different from, a sheep, for example, might view it. It’s useful for us to differentiate between human faces, but all sheep look the same to me. To a sheep, all sheep look unique and humans look the same.

What we don’t realize, however, is that the way I perceive the world is substantially different from your perception. Why? Because the way an individual experiences an environment is a mixture between sensation and perception. Sensation is the raw sensory stimuli sensory receptors and the nervous system detect from our surroundings. Perception is the process where the brain organizes and interprets that stimuli. Since each brain is unique, each person’s perception is also unique. Every individual has a different perceptual set, or mental predisposition, that influences his/her perceptions. A perceptual set may be influenced by experiences, emotions, expectations, context, or motivation. Let me give you a few examples.

Emotions:
Your emotions color your perceptions. For example, class seems longer when you’re bored. In a scientific experiment, people reported a hill as seeming steeper after hearing sad music.

Motivation:
Try to see a sea animal in this drawing.

Did you see a seal? It’s actually an ambiguous drawing, and can be viewed as a horse, but since I motivated you to see a sea animal, I altered your perception and you saw it as a seal.

Context:
The simple McDonald’s logo on a bag of french fires or the Starbucks logo on a cup of coffee itself could heighten your perception of the taste. It’s possible that Starbucks coffee really isn’t any better, but the context effect of the logo makes us perceive it as such.

So if no two people, or animals, perceive the same environment the same way, what is reality? Is there such a thing?

Perceptual Interpretation

Sensation and perception happen automatically for most of us. In fact, we tend to take the process for granted, and don’t think about how experience, emotions, or expectations alter our perceptions. Testimonies from people who don’t have this luxury make us realize how lucky we truly are.

A long time ago, in a letter to the enlightenment philospher John Locke, William Molyneaux posed the question, “Would a man born blind, and now adult, taught to distinguish objects by touch, be able to distinguish those objects by sight if they were suddenly to see?” Locke answered was no, because he believed one needed to learn to see the difference. This question, though entirely hypothetical at the time, has now been answered by modern science. John Locke was an intelligent man.

Studies have been done on adults who have had cataract surgery to regain their sight after being blind since birth. They show that no, after gaining sight they can’t distinguish objects by sight alone. This is because they don’t have the experience to form the acquired aspects of vison that you or I take for granted. So while they are able to distinguish color and brightness and figure-ground relationships (object of focus vs. backround), they can’t visually recognize objects or perceive perceptual constancy (when the image of a person gets smaller as the person walks away, they perceive the person to be physically shrinking), and struggle with facial recognition. Without touching the objects, they also struggle to differentiate between say, a picture of an apple and an actual apple. The movie At First Sight is a great example of this!

Watch a clip from the trailer. At about 1:22 he experiences some of the things I mentioned.

Another example of the wonders of perceptual interpretation is our ability to adapt to an artificially displaced or even inverted visual field. Psychologist George Stratton wore glasses that caused inverted vision (Left becomes right, up becomes down) for eight days, and he adjusted and became fully functional! In my psychology class, we mimicked his experience on a smaller scale. We put on goggles that shifted our vision field to the right or left or turned the world upside down. Then our teacher threw a teddy bear at us and asked us to catch it. At first, we went by our sensory guidance, and couldn’t catch the bear because of our displaced/inverted vison. After awhile, however, we were able to catch the bear with no problem because we learned to correct for the disparity.

Amazing.