Chapter 5 Flashcards
sensation
detection of external stimulus
perception
processing, organizing, and interpreting sensory information
selective attention
we can’t attend to everything in our environment
sensory threshold
what determines what we notice
absolute threshold
the smallest amount of a stimulus that can be detected
sensory adaption
if something is presented continuously, we decrease in sensitivity to it until it stops
bottom-up processing
based on simple input building into complex perceptions
NOT influenced by expectations
top-down processing
memory and other cognitive processes interpret and shape out perception of sensory input
influenced by expectations
example - figure ground
“mental shortcut”
vision
our eyes focus light from an image
what’s the difference between rods and cones?
rods - black and white, night vision, not much detail
cones - color, lots a detail, bright light
how does an image go from our eyes to our brain?
rods and cones – ganglion cells – optic nerve – thalamus – visual cortex
why is there a blind spot and where is it located?
where the optic nerve is, no rods or cones
color perception
wavelengths of light cause us to perceive colors in a certain way
trichromatic theory - there are 3 different types of cones that are sensitive to different wavelengths
what are two different types of color blindness and what causes it?
red and green
yellow and blue
the wavelengths for those colors are very close together so it’s difficult to tell them apart from each other
audition
the sense of sound perception
sound wave
pattern of changes in air pressure produces “sound”
frequency = pitch
amplitude = loudness
how does sound get to the brain
soundwaves – outer ear – middle ear – inner ear – auditory nerve – thalamus – auditory cortex
what is the vestibular system?
perception of balance
semicircular canals
how do cochlear implants work?
the implants stimulate the auditory nerves directly
(for those with hearing loss due to loss of hair cells)
taste
“gustation” is the sense of taste
(sweet, sour, salty, bitter, umami)
taste buds
mostly on our tongue, but some on throat and mouth
8,000-10,000
change over time
receptors send messages straight to the thalamus, then frontal lobe
what are two things that can determine taste preferences?
culture and mother’s diet (while in womb and breastfeeding)
smell
“olfaction” is sense of smell
odorants picked up by the smell receptors in the “olfactory epithelium”
information goes to the “olfactory bulb”, located under the frontal lobe
pheromones
processed like odorants
released by animals and humans that trigger psychological and behavioral reactions in others
other species rely on their sense of smell more than humans
often related to sexual signaling (smell good vs bad)
touch
“haptic” is sense of touch
sensory info from the skin - temperature, pressure, pain, kinesthetic sense (where is my body in space)
touch – sensory receptors – thalamus – somatosensory cortex
what is pain?
an experience created by the brain in response to a stimulus
what are two types of nerve fibers for pain?
fast fibers - sharp immediate pain, myelinated
slow fibers - chronic, dull, steady ache/pain, nonmyelinated
what are two types of pain
fast acting - recoil from harmful objects
slow acting - keep us from using the affected body part
