Chapter 5 - Sensation and Perception Flashcards
sensation
- when sensory information is detected by a sensory receptor (specialized neurons that respond to specific types of stimuli)
transduction
- conversion from sensory stimulus energy to action potential
- cells detect surroundings, relay messages through action potential to nervous system
absolute threshold
- the minimum amount of stimulus energy that must be present for the stimulus to be detected 50% of the time
- ex. how dim a light can be and still be detected half the time
subliminal messages
getting messages that are presented below the threshold for conscious awareness
just noticeable difference/difference threshold
how much difference in stimuli is required to detect a difference between them
perception
the way sensory information is organized, interpreted, and consciously experienced
bottom-up processing
- when we sense basic features of stimuli and then integrate them
- comes from the environment
top-down processing
- when previous experience and expectations are first used to recognize stimuli
- typically slow, deliberate, and under your control
sensory adaptation
when we often don’t perceive stimuli that remain relatively constant over prolonged periods of time
inattentional blindness
the failure to notice something that is completely visible because the person was actively attending to something else and did not pay attention to other things
signal detection theory
- the ability to identify a stimulus when it is embedded in a distracting background because you’re looking for it
- ex. showering and hearing your cell ring when expecting a phone call
attention
plays a significant role in determining what is sensed versus what is perceived
amplitude
the distance from crest (top) to the trough (bottom) of a wave
although perceptions are built from sensations…
not all sensations result in perception
wavelength
the length of a wave from one peak to the next
frequency
the number of waves that pass a given point in a given time period
hertz (Hz)
- the unit that is often used to represent frequency
- in cycles/sec
visible spectrum
the portion of the larger electromagnetic spectrum that we can see
electromagnetic spectrum
encompasses all of the electromagnetic radiation that occurs in our environment and includes gamma rays, x-rays, ultraviolet light, visible light, infrared light, microwaves, and radio waves
ROYGBIV
- how to remember the light wavelength that is associated with colors
- red is longer wavelengths, blues and violets are shorter
- larger amplitudes appear as brighter colors
pitch
- frequency of a sound wave is associated with our perception of pitch
- high frequency waves are high pitched, low freq are low pitched
decibels (db)
a logarithmic unit of sound intensity
timbre
a sound’s purity, and it is affected by the complex interplay of frequency, amplitude, and timing of sound waves
cornea
- the transparent covering over the eye
- serves as a barrier between the inner eye and the outside world
- involved in focusing light waves that enter the eye
pupil
- the small opening in the eye through which light passes
- size of the pupil can change as a function of light levels and emotional arousal
- dilates to let light in in darker areas, vice versa
iris
- the colored portion of the eye
- what controls the pupil’s size
lens
- a curved transparent structure that serves to provide additional focus
- attached to muscles that can change its shape to aid in focusing light that is reflected from near or far objects
fovea
- a small indentation in the back of the eye
- where the lens focuses images its receiving
- contains densely packed photoreceptor cells
retina
- the light-sensitive lining of the eye
photoreceptor
- light-detecting cells
- these photoreceptor cells are known as cones
- inside of the fovea
cones
- specialized types of photoreceptors that work best in bright light conditions
- very sensitive to acute detail and provide tremendous spatial resolution
- involved in our ability to perceive color
rods
- specialized photoreceptors that work well in low light conditions
- involved in our vision in dimly lit environments, perception of movement, and peripheral
- located in retina
optic nerve
- nerve carries visual information from the retina to the brain
- formed by retinal ganglion cells that connect cones and rods
blind spot
- even when light from a small object is focused on the blind spot, we do not see it
- visual system fills blind spot so not aware it exists
optic chiasm
- an X-shaped structure that sits just below the cerebral cortex at the front of the brain
- info from right visual field is sent to LEFT side of the brain and vice versa
- where optic nerve from each eye merges below brain
trichromatic theory of color vision
- all colors in spectrum can be made by combining red, green, and blue - three types of cones are each receptive to one of the colors
opponent-process theory
- another color theory, color is coded in opponent pairs: black-white, yellow-blue, and green-red
- idea is that some cells of the visual system are excited by one of the opponent colors and inhibited by the other
afterimage
- the continuation of a visual sensation after removal of the stimulus
- ex. seeing a sun spot after looking away
depth perception
Our ability to perceive spatial relationships in 3D space
binocular cues
rely on the use of both eyes to understand depth
binocular disparity
- the slightly different view of the world that each of our eyes receives
- an ex. of a binocular cue
monocular cues
cues that require only one eye
linear perspective
the fact that we perceive depth when we see two parallel lines that seem to converge in an image (e.g. a painting of a road)
____ and ___ stimuli both occur in the form of waves
visual, auditory
relationship between wave amplitude/frequency and loudness
- higher amplitudes are associated with louder sounds and vice versa
- lower freq., harder to hear and vice versa
pinna
- the visible part of the ear that protrudes from our heads
- part of the outer ear
tympanic membrane
- also known as the eardrum
- part of the outer ear
ossicles
- the three tiny bones that are part of the middle ear
malleus
- one of the three tiny ossicles bones
- also known as “hammer”
incus
- one of the three tiny ossicles bones
- also known as “anvil”
stapes
- one of the three tiny ossicles bones
- also known as “stirrup”
cochlea
- a fluid-filled, snail-shaped structure that contains the sensory receptor cells (hair cells) of the auditory system
- part of the inner ear, which regulates balance and movement
hair cells
auditory receptor cells of the inner ear embedded in the basilar membrane
basilar membrane
a thin strip of tissue within the cochlea
temporal theory
- theory that frequency is coded by the activity level of a sensory neuron
- means a given hair cell would fire action potentials related to the frequency of the sound wave
- can’t account for entire range of frequencies though
place theory
- theory that different portions of the basilar membrane are sensitive to sounds of different frequencies
- so hair cells in base portion would be labeled as high-pitch receptors, and basilar membrane would be low-pitch receptors
monaural
- one eared cues to place where a sound is coming from
- helpful in locating sounds that occur above or below and in front or behind us
binaural
- two eared cues to place where a sound is coming from
- provide information on the location of a sound along a horizontal axis by relying on differences in patterns of vibration of the eardrum between our two ears
interaural level difference
- type of binaural cue
- the difference in the intensity of a sound between the left and right ear
interaural timing difference
- type of binaural cue
- the small difference in the time at which a given sound wave arrives at each ear
- certain brain areas monitor these differences to construct where along a horizontal axis a sound originates
deafness
the partial or complete inability to hear
congenital deafness
people who are born deaf
conductive hearing loss
- condition due to a problem delivering sound energy to the cochlea
sensorineural hearing loss
When the hearing problem is associated with a failure to transmit neural signals from the cochlea to the brain
Ménière’s disease
A disease that results in sensorineural hearing loss
vertigo
- a sense of spinning
cochlear implants
- are electronic devices that consist of a microphone, a speech processor, and an electrode array
- device receives incoming sound information and directly stimulates the auditory nerve to transmit information to the brain
umami
- a Japanese word that roughly translates to yummy, and it is associated with a taste for monosodium glutamate
- a grouping of our taste
taste buds
- formed by groupings of taste receptor cells with hair-like extensions that protrude into the central pore of the taste bud
olfactory receptor
- are located in a mucous membrane at the top of the nose
- hair-like extensions from these receptors serve as sites for odor molecules dissolved in mucus to interact with chemical receptors located on extensions
olfactory bulb
a bulb-like structure at the tip of the frontal lobe where the olfactory nerves begin
pheromones
- chemical messages sent by another individual
- often involves providing information about the reproductive status of a potential mate
Meissner’s corpuscles
- respond to pressure and lower frequency vibrations
- distributed throughout the skin to respond to various touch-related stimuli
pacinian corpuscles
- detect transient pressure and higher frequency vibrations
- distributed throughout the skin to respond to various touch-related stimuli
Merkel’s disks
- respond to light pressure,
- distributed throughout the skin to respond to various touch-related stimuli
Ruffini corpuscles
- detect stretch
- distributed throughout the skin to respond to various touch-related stimuli
thermoception
- temperature perception
- nerve endings respond to a variety of different types of touch-related stimuli and serve as sensory receptors
nociception
- a signal indicating potential harm and maybe pain
- nerve endings respond to a variety of different types of touch-related stimuli and serve as sensory receptors
inflammatory pain
Pain that signals some type of tissue damage
neuropathic pain
- some situations, pain results from damage to neurons of either the peripheral/central nervous system. - - - so pain signals that are sent to the brain get exaggerated.
congenital insensitivity to pain/ congenital analgesia
- when individuals are born without the ability to feel pain
vestibular sense
- contributes to our ability to maintain balance and body posture
- the major sensory organs of this system are located next to the cochlea in the inner ear
proprioception
- perception of body position
- interact with information provided by the vestibular system
kinesthesia
- perception of the body’s movement through space
- interact with information provided by the vestibular system
Gestalt psychology
school of thought that focuses on how the human brain perceives the world as a whole, rather than individual part
figure-ground relationship
- A Gestalt principle
- we tend to segment our visual world into figure (object or person that’s focus of visual field) and ground (the background)
proximity
asserts that things that are close to one another tend to be grouped together
similarity
things that are alike tend to be grouped together
continuity/good continuation
suggests that we are more likely to perceive continuous, smooth flowing lines rather than jagged, broken lines
closure
we organize our perceptions into complete objects rather than as a series of parts
principle of closure
we organize our perceptions into complete objects rather than as a series of parts
pattern perception
- our ability to discriminate among different figures and shapes
- occurs because of principles of closure/continuity
perceptual hypotheses
- educated guesses that we make while interpreting sensory information
- informed by a number of factors
chemical senses
- tase and smell are chemical sense because they both have sensory receptors
