Sensation & Perception

sensation

detecting physical energy with our sense organs (eyes, ears, skin, nose, tongue)

perception

the brains interpretation of raw sensory information

illusions

the way we perceive stimulus doesnt match its physical reality

transduction

conversion of an external stimuli into a neural signal

sensory receptors

specialized cells that convert external info into a neural signal (does transduction)

sensory adaptation

sensory neurons adjust their sensitivity based on recent stimulus history

aftereffects

opposing sensory or perceptual distortions that occur after adaptation

light waves

waves that correspond to light

sound waves

waves that correspond to sound

for light, wavelengths correspond to…

color

for light, amplitude correspond to…

brightness

for sound, wavelengths correspond to…

pitch

for sound, amplitude correspond to…

loudness

psychophysics

study of how our sensations corresponds to the physical events in the world.

absolute threshold

lowest level of stimulus needed for the nervous system to detect a change 50% of the time

just noticeable difference

the smallest change in the intensity of a stimulus that we can detect 50% of the time

weber’s law

the stronger the stimulus, the bigger the change needed to detect it

signal detetction theory

how stimuli are detected under different conditions

signal

what you are trying to detect

noise

similar stimuli that competes with the signal & interferes with your ability to detect the signal

signal-to-noise ratio

difficulty of detecting the signal depends on the strength of the signal in relation to the strength of the noise

attention

the spotlight of experience

dichotic listening

playing different info through each ear of headphones, information is reported only from the attended ear

cocktail party effect

important info pops out of a conversation that you are not attending to (ex. your name)

inattentional blindness

when unattended stimuli are ignored as if they aren’t there

change blindness

when you fail to detect obvious changes in your environment that you weren’t paying attention to (visual)

bottom-up processing

constructing a presentation from parts & basic features (sensation)

top-down processing

processing influenced by previous experience & knowledge (perception & sensation)

perceptual sets

set formed when our expectations influence our perception (ex. 13 & B)