AP Psychology
Guided Notes #5
Fall Semester 2014
Bacile
Unit V: Sensation & Perception
Corresponding Module: 16-21
Topic: Sensation & Perception (6-8%)
SENSATION & PERCEPTION: VISION
 Vision, hearing, smell, taste, touch, pain and body position
o Similarities?
 ________________________________________________________________________________________________
 More sensitive to change than to constant stimulation
 Provide us with information regarding ___________________________________________________
o Differences?
 Each requires ________________________________________________________________________________
 Each sends information to a different region of the brain for processing
Sensation: Vision
Vision: The Stimulus Input
 The Stimulus Input
o Light energy (electromagnetic spectrum)
 Two physical characteristics help to determine our sensory experience of light
o Wavelength
o _____________________________________________________________________
o _____________________________________________________________________
o Amplitude
o ____________________________________________________________________
o ____________________________________________________________________
Vision: The Structure of the Eye
 CORNEA
o Location/Structure
 ______________________________________________________________________________________________
o Function
 Protects the eye
 Bends light towards a central point in order to _______________________________________
 PUPIL & IRIS
o Location/Structure
 ______________________________________________________________________________________________
 Surrounded by the iris (__________________________________________________________________)
o Function
 Controls the amount of light that is able to enter the eye
o In ____________________________________________________
the iris __________________________, making the
pupil smaller
o In ____________________________________________________
the iris __________________________, making the
pupil larger
 LENS
o Location/Structure
 A transparent structure that is located behind the pupil
o Function
 Focuses image on the back of the eye (retina)
o Accommodation
o The process by which the ___________________________________________________________________ to help focus
near or far objects on the retina
 Lens Problems
o Nearsightedness
 _________________________________________________________
 _________________________________________________________
 Image focused in front of the retina
o Farsightedness
 ________________________________________________________
 ________________________________________________________
 Image focused behind retina
 RETINA
o Location/Structure
 A multilayered, light-sensitive surface located
at the back of the eyeball
o Function
 Contains cells that ___________________________________
_________________________________________________________
 Includes three layers of cells
o ______________________________________________ (photoreceptors – cones & rods)
o ______________________________________________
o ______________________________________________
Three Layers of Retinal Cells
Photoreceptor Cells (Cones & Rods)
Cones
Number
Location
(in the retina)
Color sensitive?
Sensitivity in dim
light?
Ability to detect
sharp detail
(acuity)?
Bipolar Cells
Rods
Ganglion Cells
Light energy  Cones & Rods  Bipolar Cells 
Ganglion Cells
 OPTIC NERVE
o Location/Structure
 ________________________________________________________________________________________
o Function
 Sends visual information to the thalamus and then to the occipital lobes
 Where the optic nerve leaves the eye, ____________________________________________________________________________________________
Vision: Visual Processing
 Feature Detectors
o _________________________________________________________
o Nerve cells in the brain that respond to specific features
 ______________________
 ______________________
 ______________________

Parallel Processing
o _________________________________________________________________________________________________________________________________
 The brain divides a visual scene into color, depth, form and movement
Vision: Color Vision
 Young-Helmholtz Trichromatic Theory
o (Hermann von Helmholtz & Thomas Young)
 The theory that the retina contains _______________________________________________________________________________________________
 When stimulated in combination, these receptors can produce the ___________________________________________________________
o Color Blindness?
 Dichromatic Color Vision
 Individuals ________________________________________________________________; usually the red or green receptor
 Opponent-Process Theory
o (Ewald Hering)
 _______________________________________________________________________________________________________________________________________

_________________________________

_________________________________

_________________________________

Light that stimulates one half of the pair inhibits the other half

For example, some cells are stimulated by green and inhibited by red, while others are stimulated by red
and inhibited by green