Ch 8 Sensation Perception Sensation Perception Sensation physical

Ch. 8: Sensation & Perception

Sensation & Perception Sensation – physical process of getting info from senses Perception – brain’s process of interpreting sensations -affected by: illness, stress, personality, experiences, cognition

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

Psychological (Cognitive) Effects on Perception Absolute threshold (p. 210) -abs. limit of what we can sense Difference Threshold -ability to sense minute changes

Sensory Adaptation -more aware of weak stimuli than unchanging stimuli (ex: movement in trees even in a slight breeze) -used for protection; allows us to react Signal Detection -ability to concentrate on necessary stimuli -susceptible to Stroop Effect (p. 213)

The Senses: Vision Here is how we see: Pupil Allows light Lens Focus Retina Stores image Photoreceptors Neurons in retina Optic Nerve Sends info Occiptial Lobe Interprets

Vision Terms Blind spot – optic nerve leaves eye Neurons - Rods - black & white - Cones – color Light - Electromagnetic spectrum – wavelengths allow color After image – complimentary colors

Color Blindness – cones don’t fire Retinal Disparity – eyes perceive different depths -monocular cues -binocular cues Binocular Fusion – blending into one image

The Senses: Hearing How we hear: airwaves vibrate from one part to the next Ear Drum Hammer Middle Anvil Ear Stirrup Cochlea – inner ear Auditory Nerve Temporal Lobe

Hearing Pitch – high/low -# (frequency) of waves -more waves = higher pitch Volume – loud/soft -height of waves -higher waves = louder sound

Deafness Conductive -damage to middle ear (amplifier) -hearing impaired Sensorineural -neurons in cochlea damaged -common, gradual hearing loss

Other Senses: Chemical Senses Smell & Taste Smell -food gives off gases olfactory nerve pariental lobe Taste -bitter, salty, sweet, sour -other tastes from smell

Other Senses: Skin Senses Pressure -receptors at base of hair Temperature -receptors in skin Pain -receptors in skin (prostoglandins) prostoglandins -gate theory: only one skin sense processed at a time

Other Senses: Body Senses Vestibular Sense -in ears -upright, falling Kinethesis -body position

Perception

Perception -a learned response -subliminal perception – beyond threshold Basic Principles 1) Gestalt -whole experience -includes: (p. 224) proximity closure simplicity similarity continuity

2. Figure Ground -need background 3. Interference -illusions -depth perception -monocular cues -binocular cues Assignment: Find computer examples of the Gestalt illusions & figure ground. Copy, paste and label each illusion.

Assignments • Computer Illusions • Ch. 8 Test