9/16 - Exam 2
● Perception is the process of organizing and interpreting sensory information so that it
has meaning
○ Recognizing what we see, hear, feel, taste, and smell
○ Identifying distal (actual) things from proximal (sensory) information
○ Assessment
■ The study of the correspondence between the physical characteristics of
a stimulus and our psychological experience of that stimulus is known as
psychophysics (studying perceptual proficiency) (psychophysics employs
numerous measures)
○ Psychophysics
■ The absolute threshold is the smallest amount of sensory stimulation that
can be consciously detected
● Subliminal sensation (fact) (can influence our responses)
● Subliminal influence (fact)
● Subliminal persuasion (mostly fiction)
● The brain can register sensations without us being aware of them
■ The difference threshold is the smallest change in sensory intensity that
can be consciously detected
● The “just noticeable difference”
● Follows Weber’s law where stimuli must vary by a certain
percentage to be recognized as different
■ The recognition threshold is the smallest amount of sensory information
required for a known entity to be identified
● Elements of perception
○ Sensation is the detection of external stimuli energy by sensory organs
, ■ Sight (Vision) is the most highly developed and important sense for
humans and most other mobile animals
● Color vision
○ Stages
■ Particles of energy (photons) are emitted from light
sources
■ Photos reflect off of surfaces at different
wavelengths
■ The retina contains three types of cones each
responding best to a different wavelength of light
(trichromatic theory [young-helmholtz, 1852])
● S cones are shortwave (blue)
● M cones are mediumwave (green)
● L cones are longwave (red)
■ Outputs from cones are transmitted to ganglion
cells via bipolar cells
■ “X” ganglion cells transmit color information to the
visual cortex via three channels (opponent-process
theory [Hering, 1878])
■ Wavelength information is combined with and
interpreted by the visual cortex allowing us to
perceive many different colors and shades
■ Sound
● Audition is the sense that compliments vision by allowing us to
orient our gaze toward sounds, or to hear things before seeing
them
● Perception is the process of organizing and interpreting sensory information so that it
has meaning
○ Recognizing what we see, hear, feel, taste, and smell
○ Identifying distal (actual) things from proximal (sensory) information
○ Assessment
■ The study of the correspondence between the physical characteristics of
a stimulus and our psychological experience of that stimulus is known as
psychophysics (studying perceptual proficiency) (psychophysics employs
numerous measures)
○ Psychophysics
■ The absolute threshold is the smallest amount of sensory stimulation that
can be consciously detected
● Subliminal sensation (fact) (can influence our responses)
● Subliminal influence (fact)
● Subliminal persuasion (mostly fiction)
● The brain can register sensations without us being aware of them
■ The difference threshold is the smallest change in sensory intensity that
can be consciously detected
● The “just noticeable difference”
● Follows Weber’s law where stimuli must vary by a certain
percentage to be recognized as different
■ The recognition threshold is the smallest amount of sensory information
required for a known entity to be identified
● Elements of perception
○ Sensation is the detection of external stimuli energy by sensory organs
, ■ Sight (Vision) is the most highly developed and important sense for
humans and most other mobile animals
● Color vision
○ Stages
■ Particles of energy (photons) are emitted from light
sources
■ Photos reflect off of surfaces at different
wavelengths
■ The retina contains three types of cones each
responding best to a different wavelength of light
(trichromatic theory [young-helmholtz, 1852])
● S cones are shortwave (blue)
● M cones are mediumwave (green)
● L cones are longwave (red)
■ Outputs from cones are transmitted to ganglion
cells via bipolar cells
■ “X” ganglion cells transmit color information to the
visual cortex via three channels (opponent-process
theory [Hering, 1878])
■ Wavelength information is combined with and
interpreted by the visual cortex allowing us to
perceive many different colors and shades
■ Sound
● Audition is the sense that compliments vision by allowing us to
orient our gaze toward sounds, or to hear things before seeing
them
