2. The images are exactly the same except for the thick black area in the right image
(an example of the Poggendorff illusion (1860)). In the figure on the right, there
appear to be two continuous diagonal lines: a red and a blue line. What occurs in
your visual system that could account for the appearance of the continuous
diagonal lines?
8. Gestalt Psychology
• Gestalt means “an organized whole”
• These psychologists emphasize our
tendency to integrate pieces of
information into meaningful wholes
14. Perceptual Constancy
• We perceive objects as being stable and
unchanging despite the fact that sensory
information changes all the time.
• Size Constancy- depends upon
experience and distance cues. In the
absence of distance cues, we still are
pretty accurate despite the disparity
between the retinal image and reality.
15. • Shape constancy – We see an object as the
same shape no matter what angle we view it
from.
• Brightness Constancy- Brightness remains the
same even though the amount of light reaching
the retina changes constantly.
• Color Constancy- Color remains the same
despite the change in light. However, if we are
unfamiliar with a color it can look different in
different light. That’s why you paint a part of a
wall and view it over the course of a few days
rather than buy 4 gallons of paint right away.
16. Observer characteristics
• 1) Motivation-
• 2) Values
• 3) Expectations- we delete, transpose
modify and insert things into what we
perceive
• 4) Cognitive Style- field dependent vs. field
independent
• 5) Experience and Culture- Mbuti pygmies
• 6) Personality
17. Binocular Cues
• The combination of two retinal images gives a 3-
D perceptual experience. This is called
Stereoscopic vision.
• Our eyes are set about 2 ½ inches apart so we
get a diff. view from each eye. The diff between
images is called Retinal Disparity.
• Also, our eyes turn inward to view things that
are close to us. This is called Convergence
18. Sound Cues
• Monaural Cues- only need one ear
• 1) loud sounds are closer than faint
sounds
• Binaural Cues- both ears are necessary
• 1) since sounds from one side hit the ear
at diff. times, we can judge direction.
(“Sound localization”)
19. Perception of Movement
• Real Movement- We perceive things as moving
relative to a stable background. This is generally
accurate. We are also especially attuned to
Biological Movement.
• Apparent Movement occurs when we perceive
movement in stationary objects.
• 1) Autokinetic Illusion- in a dark room, a single
point of light will appear to move because our
eye muscles are constantly moving. In the
absence of other visual data, our eyes cannot
“hide” that fact.
20. • 2) Phi phenomenon- This when lights flash
in a quick sequence and we perceive
motion.
• http://www.yorku.ca/eye/balls.htm
• 3) Stroboscopic motion- apparent motion
caused by rapidly flashing still pictures.
This is how motion pictures work.
