PERCEPTIONCRASH COURSE

The process of organizing and interpreting information, enabling us to recognize meaningful

objects and events.Seeing the world as it isn't

Stare at the blue dot in the middle. You should see the outer edges of the circle fade away!

Troxler’s fadingIt occurs because even if our eyes move a little when we are fixating a point, away from that point, in the perception field, the movements aren’t large enough to observe other elements; in conclusion the neurons remain focused on the main object and our visual system doesn’t involve new ones for the other elements.

You are about to witness the perpetrator of a crime!

Describe who you saw at the crime scene. Keep in mind your eyewitness testimony could be used in a court of law.

Was she a young girl or an old woman???

Perceptual Ideasan illusion

Perceptual set: a mental predisposition to perceive one thing and not another.

Context Effects• Based on immediate context, not

schemas.• You do not hear the word, but can guess

at it based on the context it was said in.

Top-Down Processing• We perceive by filling

the gaps in what we sense.

• I _ant ch_co_ate ic_ cr_am.

• Based on our experiences and schemas.

• Perceptual Set – a mental predisposition; the experiences, assumptions, and expectations that influence our perception

Perceptual Adaptationinverted visionprogram 7: start @ 15:39

• The ability to adjust to an artificially altered visual field

Are the red lines parallel???http://www.michaelbach.de/ot/

Gestalt Psychology• Gestalt – an organized whole; from German

for “form” or “whole”• Gestalt psychologists emphasized the

tendency to integrate pieces of information into a meaningful whole.

• Gestalt Psychology says that we innately look at things in groups, not as isolated elements.

• “The whole is greater than the sum of its parts.”

Grouping & Gestalt Psychology

Khan Academy• Proximity - group objects that are close together as being part of same group

• Similarity - objects similar in appearance are perceived as being part of same group

• Continuity - objects that form a continuous form are perceived as same group

• Connectedness – objects that are uniform and linked are perceived as single units

• Closure - we fill gaps to create a whole or complete image

Closure

Figure Ground RelationshipVisually, our first

perceptual decision is “What is the figure?” in the image and “What is the

ground?” (background).The figure ground relationship can

also be applied as a principle of auditory perception.

Depth Perception• Eleanor Gibson -

Visual Cliff Experiment• If you are old enough

to crawl, you are old enough to see depth perception.

• We see depth by using two cues that researchers have put in two categories: – Monocular Cues– Binocular Cues

Sensory RestrictionBlakemore & Cooper, 1970

Kittens raised without exposure to horizontal lines later had difficulty perceiving horizontal bars.

Binocular CuesKhan Academy

• We need both of our eyes to use these cues.

• Retinal Disparity - as an object comes closer to us, the differences in the images for our eyes becomes greater. “finger sausage” 3-D movies

• Convergence - as an object comes closer, our eyes have to come together to keep focused on the object

Monocular Cueskhanacademy(start 2:00)

• You really only need one eye to use these (used in art classes to show depth).– Linear Perspective– Interposition– Relative Size– Texture Gradient– Light / Shadowing

Motion Perception• Stroboscopic Effect

a rapid series of slightly varying images perceived as moving images (flip book, “old” movies)

• Phi Phenomenonillusion of movement created when two or more -----lights next to each other blink on and off

Constancykhanacademy(start @ 6:10)

• Objects change in our eyes constantly as we or they move….but we are able to maintain content perception

Shape ConstancySize ConstancyColor ConstancyBrightness

Constancyo However, color and

brightness also depends on context!

Parapsychology• the study of

paranormal phenomena, including ESP and psychokinesis

• ESP – extrasensory perception; perception outside of sensory perception – Telepathy– Clairvoyance– Precognition

FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF MANY YEARS.

FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF MANY YEARS.