Perception

Objectives:

  1. Explain how illusions help us understand perception.

  2. Discuss Gestalt psychology's contribution to our understanding of perception.

  3. Explain the figure-ground relationship, and identify the principles of perceptual grouping in form perception.

  4. Discuss research on depth perception involving the use of the visual cliff, and describe the binocular and monocular cues in depth perception.

  5. Describe stroboscopic movement and the phi phenomenon.

  6. Describe the perceptual consistencies and show how the perceived size distance relationship operates in visual illusions.

  7. Describe the debate over the role of nature or nurture in perception, and discuss what research findings on sensory deprivation and restored vision have contributed to this debate.

  8. Explain what the use of distorting goggles indicates regarding the adaptability of perception.

  9. Discuss the effects of sensory restriction.

  10. Discuss the effects of experiences, assumptions, expectations, and context on our perception.

  11. State the claims of ESP, and explain why most research psychologists remain skeptical.

Vocabulary:

Visual capture- the tendency for vision to dominate the other senses

Gestalt- an organized whole- Gestalt psychologists emphasize our tendency to integrate pieces of information into meaningful wholes

Figure-ground- the organization of the visual field into objects that stand out from their surroundings

Grouping- perceptual tendency to organize stimuli into coherent groups

depth perception- the ability to see objects in three dimensions although the images that strike the retina are two-dimensional; allows us to judge distance

visual cliff- a laboratory device for testing depth perception in infants and young animals

binocular cues- depth cues, such as retinal disparity and convergence, that depend on the use of two eyes

monocular cues- depth cues, such as linear perspective and overlap, that depend on one eye alone

retinal disparity- important cue to the relative distance of different object, the greater the difference the closer the object is to the viewer

convergence- binocular cue for perceiving depth, the extent to which the eyes converge inward when looking at an object

interposition- if one object partially blocks our view of another, we perceive it closer

relative size- assume that two objects are similar in size, the smaller one to our retina is farther away

relative clarity- hazy objects farther away than sharp

texture gradient- objects far away appear smaller and more densely packed

relative height- perceive object higher in our field of vision as farther away

relative motion- as we move object that are actually still, may appear to move

linear perspective- parallel line, appear to converge with distance

light and shadow- given two identical object, the dimmer one seems farther away

Phi phenomenon- an illusion of movement created when two or more adjacent lights blink on and off in succession

Perceptual constancy- perceiving objects as unchanging even as illumination and retinal images change (consistent lightness, color, shape, and size

Perceptual adaptation- in vision- the ability to adjust to an artificially displaced or even inverted visual field

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

ESP- the controversial claim that perception can occur apart from sensory input- includes telepathy, clairvoyance, and precognition

Parapsychology- the study of paranormal phenomena, including ESP and psychokenisis