Perception is active, not passive. We attack you incoming data as it arrives. We don’t wait. We use rules to help us process things more quickly. Perception -principles are primarily simple, fast, and efficient rules. They include sorting like items together and scariest things first. Simple rules are combined into complex ways of locating objects, identifying friends and avoiding enemies.

The earliest school of psychology to focus on perception  principles was the Gestalt school. Contemporaries of the Structuralists, the Gestalt group rejected the reductionism of looking for elemental perceptual structures. They believed perception was more global. It is not like chemistry. It is more like astronomy; think big.

Gestalt is German for shape or form (roughly translated). It was a pre-cognitive theory based on perception research. But the research was unique. Gestaltists preferred to find an illusion or perceptual experience and discuss it. These biotic experiments were more experienced than controlled. They often occurred in natural settings candy real people as subjects. There was little need for trained introspectionists or double-blind studies .The emphasis was on the integrated whole.

Gestalt theory is often summarized as “the whole is greater than the sum of its parts.” It is not the small structures. It was not the functional process. The important thing is the perceptual experience itself.

In Gestalt theory, think is the interconnection of thoughts. This principle of totality proposes that conscious thought is a relational complex. Thinking is the process of self-organizing tendencies. We are organizing and structuring our understanding of the world.

 

Figure-Fround

Probably the best known organizing principle is figure-ground. When we look at an image, we decide what is important (figure) and what can be ignored (ground). We can switch from one important thing to another but we can’t see both at once. We can see the vase or the faces.

We determine what is figure by looking for a bounded (closed) area. In this example, the white is unbounded; it flows around and through the image. The black areas are more closed, and tend to be noticed first.

Figure-ground works best with symmetric areas. Unbalanced images are less effective. Smaller, convex and brighter area are also cues for figure.

A major factor is meaningfulness. We orient ourselves to things that matter to us.

In a broader sense, figure-ground is a good example of how we handle ambiguous figures. We find an explanation, look for other explanations, and switch back and forth between them. The switch is sudden, not a gradual fading or morphing from one to another. This process of multistable perception is indicative of how we process information. We collect as large of a chunk we can, compare it to our database of prior events, make our best guess, and then rethink too. The more ambiguous the situation, the more rethinking goes on.

 

Similarity

We tend not to see this as seven dots but as dots of different color or shades. We sort similar things together. The whole idea of team uniforms is to make it easier to identify which side is ors.

Angle

Similarity is not limited to color. It is a more general rule. We we sort things by similarity of angle, tone, rhythm and melody. We look for similarities of brightness, shapes and faces. We try to simplify incoming data by categorizing as much as we can.

Form

Best form, closest thing to what you know, almost fits the pattern you have previously stored. Not a G but close enough.

Pragnanz

Gestalt theory would fit well with minimalism. There is a preference for the simple, orderly, and symmetrical; perfect for those of us who tend toward having OCD.

Pragnanz is a broader principle than best form of a single figure. It is a fundamental principle of perceptual organization. We filter incoming stimuli, eliminating complexity as much as possible. Our perceptual system prefer simple, family and slow moving stimuli. We can handle difficult inputs but we process it reluctantly.

Unfamiliar stimuli are handled as exceptions to the rules. We don’t like extraneous stimuli or ambiguity. We prefer a string of whole entities, not a stream of bits. Our aversion to ambiguity is true of all senses but it is easiest to demonstrate in vision.

 

Invariance

We see objects as wholes. Based on our experience, we know a cell phone is the same regardless of its orientation. But when we are searching for on a desk covered with papers, we expect to see it in its entirety. It is hard to recognize an object on its side. It’s only when we think about it that we search for the color of the case, the shine of the screen or the thinness of the edge.

Good Continuation

When we look at an object, we think of its most likely construction. We don’t think of two odd objects put together to make a common one. When we see a cross, we think of two straight lines intersecting, because that is how we would do it. We estimate the most likely configuration.

Proximity

We sort things that are close to each other. We tend to see this as a cluster of three items and a cluster of 4 items. The tendency is even stronger if all the dots are the same color.

Closure

We don’t like incomplete objects, so we add the missing pieces ourselves. Here is a box, or an almost box. We close figures as needed.

Symmetry & Convex

This two sets, three items or four items. Our preference is two sets of brackets. We don’t like open brackets. Maybe it is our trading in mathematics but we want open brackets m like doors, to be closed.

[         ]{       }

 

Law of Past Experience

We tend to see this as two letters, not a U needing closure. In our experience, letters are more common than closure. We might wonder if it is two different letters or one letter in two cases, but we tend to go with the letter explanation.

Set & Context

Our knowledge of English makes it more likely to be the start of LIKE. Lloyd has repeated Al’s but other examples come to mind more slowly. In Spanish, Icelandic, and Albanian, the double L is more common. Notice that a shorter middle character here would shift the context more.

Similarly, the middle item here could be a B or a 13, depending on the context.

Common Fate

Birds moving in same direction are presumed to be headed to the same place. If always surprises us when the split into separate groups and fly off in different directions. We like simple explanations.

Focal Point

We focus on the first unused thing we see. This is an example of primary distinctiveness. Something distinctively different is the environment gets our fullest attention.

Reification

This is the brain making more of what is actually there. We add to actual information until it makes sense to us. There is no triangle here but we see one. This is the brain augmenting reality.

Phi Phenomenon

Implied movement of theater light’s or neon signs telling you where to eat are attention-getters. We orient to movement. Max Wertheimer’s phi phenomenon takes good advantage of our preference for movement. Nothing is actually moving but a sequence of lights turning on in order suggests movement to us. It is an approximate of the real thing.

Top-down processing

Humans are very sensitive to language. We scan incoming signals to identify anything we can read. The Stroop Effect shows how quickly we process written words. Ignore the word (impossible) and say to color it is printed in. Do it out loud for the full effect.

The first word probably went quite well, the second was harder, and the 3rd or 4th tripped you up. A long list is even worse. The brain had to look at the color but it couldn’t ignore the word. Language is so important, we search it out.

Bottom-up processing

The Coke-Pepsi challenge shows how different parts of the brain have different functions. One part of the pre-frontal cortex (PFC) interprets taste. Another keeps track of rules and bands,

If you take the challenge blindfolded, you’re likely to pick Pepsi. The sweet, Carmel and salty sensations taste good. this is bottom-up perception.

‘If you can see the logo, or in Coke’s case the distinctive bottle, you prefer Coke. This is top-down processing.

Interpretation

The involvement of the brain on perception cannot be overstated. Humans are thinkers. When we see something scary, we perceive that object as bigger. The person who yelled at us wasn’t just tall, he was super tall. A rock is a bolder, a dart is a spear, a pony is a horse.

Imagine you are on a boat walk from stem to stern. You look in the cabin window and see a plate of cookies on the table. Most people zoom in on the plate of cookies. Like a movie director, we get a close up shot of the food. We also zoom in real life. Our eyes don’t have a zoom feature but our brain does. If it is important, it takes up the whole frame.

When we are adding to reality, we are not limited to flat images. We can create our own 3-D objects.

Illusions

Gestalt psychology loves illusions. They are so interesting and consistent. Illusions are false perceptions. They are systematic perceptual errors. They show the flaws in our systems.

People don’t perceive length, area, angle, brightness the way they “should.” We don’t do it simply. We adjust our systems to the environment. We use our brains.

 

Brightness contrast

A gray square on white background looks pretty gray. But put it against a dark background, it looks darker. We don’t measure actual gray-ness, we use relative gray. We don’t track actual speed; we know which horse is running faster. We are very good at relative judgements.

Delboeuf Illusion

This illusion asks you to compare two lines, one with regular arrow heads, and one with reversed arrow heads. The lines are the same length. Compare them yourself. But that is not what your mind says.

Estimation

Our measuring systems are very practical. We have great binocular vision within 20 feet, the practical distance for throwing a rock to kill dinner. We can accurately estimate height up to about 25 feet. But given a four-story building, we tend to overestimated its height by 25%. Anything over w stories is tall. Anything over 4 stories is really tall. At some point we give up direct estimates and count windows.

Horizontal-Vertical Illusion

These two lines are the same length but the vertical one looks longer. And the longer you stare at it, the taller the vertical line seems to be.

Impossible Objects

Some creations of ours are fun and impossible. They don’t exist in the real word.

The People

Max Wertheimer (1880-1943)

Best known for exploring the phi phenomenon, Wertheimer challenged Wundt’s explanation as being the result of eye movement. The perception of apparent movement is proof for the Gestalt theorists that we perceive things as a whole experience.

Kurt Kofka (1886-1941)

Like Wertheimer, Koffka was a student of Stumpf. He assisted Wertheimer in many of his experiments. He maintained that perception should not be thought of as a narrow focus on a single process. Gestalt perception is broader that that. They are general processes of our minds.

Wolfgang Köhler (1886-1941)

The third pioneer of Gestalt psychology, Kohler is better known for his research into chimpanzees’ intelligence.

 

Depth Perception

Want to jump ahead?

• What Is Perception?
• Perceptual Efficiency
• Vision
  • Principles
  • Depth
  • Light & Eyes
  • Eye
  • Retina
  • Color Vision
  • LGN
  • Occipital Lobe
  • Pathways
• Taste
  • Simple
  • Tongue
  • Throat
• Smell
  • Basic
  • Nose
  • Olfactory bulb
• Flavor
• Touch
  • Receptor
  • Pressure
  • Haptic Perception
  • Temperature
  • Pain
  • Itch
• Hearing
  • Ear
  • Cochlea
  • Pathway
  • Temporal Lobe
• Vestibular
• Visceral
• Proprioception
• Time

Photo by Rafael Leão on Unsplash