Lesson 7: Form Perception

Form Perception

The Gestalt Psychologists studied extensively form perception, or the perception of objects, shapes and patterns. Gestalt principles may be broken down into two categories: perceptual organization (grouping) and depth perception. 

 

Gestalt Principles of Perceptual Organization

  • How objects are grouped together Links to an external site.
    • Continuity
      • We tend to perceive figures or objects as belonging together if they appear to form a continuous pattern
    • Closure (Connectedness)
      • We perceive figures with gaps in them to be complete
    • Similarity
      • We perceive figures which look alike as being grouped together
    • Proximity
      • We perceive things close together as being in sets
    • Pragnanz
      • We perceive reality in the simplest way rather than inferring complexity 

Take a minute to take some notes: How are Gestalt grouping principles used in The Human Condition (above)

Monocular depth cues 

  • Depth cues that can be perceived by only one eye
    • Interposition
      • When one object partly blocks your view of another, you perceive the partially blocked object as farther away
    • Linear perspective
      • Parallel lines that are known to be the same distance apart appear to grow closer together, or converge, as they recede into the distance
    • Relative size
      • Larger objects are perceived as being closer to the viewer, and smaller objects as being farther away
    • Texture gradient
      • Near objects appear to have sharply defined textures, while similar objects appear progressively smoother and fuzzier as they recede into the distance
    • Atmospheric perspective
      • Objects in the distance have a bluish tint and appear more blurred than objects closer to the viewer 

 

 Take a minute to take some notes: How are depth cues used in The Human Condition (above)

Gestalt principles help explain how we perceive distance, depth, organization and harmony on a 2 dimensional canvas. 

 

Visual Perception in a nutshell – our visual perceptual system works to heighten differences and impose constancies to help us survive in the big, scary world, often causing disparities between what we see and the physical world.

Or, as Aristotle succinctly put it:  “our senses can be trusted but they can be easily fooled.” 

For example, in the image below both of the orange (middle) circles are exactly the same size. This one of many visual illusions, called the Ebbinghaus Illusion, which explore the effect of context on perception. Our visual system compares the circles and exaggerates the differences between them. 

Ebbinghaus Illusion 

 

 

Another illusion can be seen in the corner of any room. Mach bands form when two uniformly shaded areas meet - the difference in shade will be exaggerated at the juncture. In other words, there will be a small strip that is a bit darker and a small strip a bit lighter where they meet. To demonstrate, look closely at where one shade meets another in the image below:

Mach Bands

Other Perceptual tricks can be found and described here Links to an external site..