Chapter 5 & 6
absolute threshold
A drop of perfume in a 6-room house. example of
top-down processing
Imagine that you are driving down an unfamiliar street and you see a sign for a convenience store. The sign has several missing letters, but you're still able to read it. Why?
convergence
In order to perceive depth properly, your eyes must move slightly inward
relative clarity
Objects that appear sharp, clear, and detailed are seen as closer than more hazy objects
linear perspective
Parallel lines that converge appear far away.
selective attention
Selective attention is purposely focusing your conscious awareness onto a specific stimulus. This means that if you are in a noisy place with lots of people and you purposely pay attention to the person you are speaking with, you are engaging in selective attention. Easy enough, right? So how is this different from "paying attention" or simply "attention"? I know there are subtle differences, but it seems redundant to me.
texture gradient
Smaller objects that are more thickly clustered appear farther away than objects that are spread out in space.
iris
Specifically it is a ring of muscle tissue that not only forms the colored portion of the eye around the pupil, but also is responsible for controlling the size of the pupil opening.
perception
The brain interprets pain, signals to 'move the foot,' and visualizes a tack or nail. This is example of
webers law (Gustav Fechner)
The law states that the change in a stimulus that will be just noticeable is a constant ratio of the original stimulus
pupil
The opening in your eye that allows light to enter. The light then hits your neural receptors which transforms the stimulus into neural impulses which can be interpreted by your brain (mainly, the occipital lobe).
rods and cones (retina) (also called photoreceptors)
They are responsible for transmitting sensations of light and color to form, and transmit to the brain, images of what the eye is seeing,
perceptual adaptation
This refers to the ability of the body to adapt to an environment by filtering out distractions. For example, someone who lives near a train can perceptually adapt such that they can ignore the train whistle in order to sleep at night.
blind spot
Visual information travels along the optic nerve in the eye before it begins its journey to the brain for processing. There is a certain spot on the optic nerve that does not have any receptor cells (the area where the optic nerve leaves the eye), and, as a result, can't receive information.
volley theory
Volley Principle is part of a hearing theory that was proposed by the research team of Weaver and Bray in 1937. It states that when high frequency sounds are experienced too frequently for a single neuron to adequately process and fire for each sound event, the organs of the ear, specifically the organ of Corti that is found in the cochlea, combine the multiple stimuli into a "volley" in order to process the sounds.
sensory adaptation
When you are wearing a new wristwatch or ring, you may at first be aware of the sensation of pressure on your skin, but after a while you no longer notice it. example of
lens
When you try to focus on something this changes the shape (called accomodation) and then focuses the incoming light onto the back of the eye (the retina) which send the information on to be processed by the brain.
sensation
Your hearing senses detect a loud rumble coming from a distance. This is an example of
retinal disparity
a binocular cue for perceiving depth by comparing images from the retinas in the two eyes, the brain computes distance—the greater the disparity (difference) between the two images, the closer the object.
basilar membrane
a long membrane that is part of the auditory system. The membrane runs the length of the cochlea (inside the ear) and contains those tiny hairs that act as sound receptors.
Decibels
a measure of sound intensity
priming
a person who sees the word doctor will be faster to recognize the word nurse than he will be to recognize an unrelated word because the concepts are closely associated. example of
cochlear implant
a small electronic device surgically implanted in and behind the ear to help deaf people hear. The implants do not restore hearing completely, but they allow sound to bypass damaged cells in the inner ear and stimulate the auditory nerve directly, thereby helping people with profound to severe hearing loss perceive sound.
visual cliff
a test given to infants to see if they have developed depth perception.
bipolar cells
a type of nerve cells that combine the impulses from many of the visual receptor cells in the retina and then transmits those impulses to the ganglion cells
Interposition
a visual signal that an object is closer than the ones behind it because the closer object covers part of the farther object. For example, you know that your keyboard is closer than your desk because you see the desk around the keyboard.
sound localization
ability to determine the location of a sound and where it is coming from
vision
ability to interpret the surrounding environment using light in the visible spectrum reflected by the objects in the environment
subliminal stimulation
advertising rely on that concept and is the practice of using words or images (stimuli) that consumers don't consciously detect. example of
inattentional blindness
also known as perceptual blindness, is an event where the effected person doesn't see new and unexpected things that suddenly appear within their visual field. This phenomenon is believed to be a side-effect of excessive stimuli in the visual field (too many things to keep track of at the same time) and can cause a person to miss important,
auditory nerve
also known as the Cochlear or acoustic nerve, is a sensory nerve, it is found in the head and transmits information from the inner ear (cochlea) to the brain in the form of sound (acoustic) energy that impinges on the ear drum
brightness
amplitude or intensity determines a light's
subliminal stimulation
anything below the threshold, not able to consciously detect a stimulus
feature detectors
are individual neurons—or groups of neurons—in the brain which code for perceptually significant stimuli.
light and shadows
are used by the visual system as cues to determine depth perception and distance. can also highlight three dimensional elements from a two dimensional image.
outer ear
auditory canal to the pinna, a tight membrane that vibrates
perceptual set
describes a tendency to perceive some sensory stimuli and to ignore others.
cocktail party effect
describes the the ability to focus your hearing on one specific thing even though noise is all around you. It is named such because this occurs when you are at a party- you can focus on the conversation you are having with the person close to you and can ignore all of the other noise and conversation going on around you. Your brain helps you selectively focus on the person you are talking too and 'mutes' the other conversation, music, and general noise around you.
relative height
distant objects are seen or portrayed as being smaller and higher in relation to items that are closer
precognition
e ability to actually perceive or see a future event through extrasensory perception
closure
explains how humans fill in visual gaps in order to perceive disconnected parts as a whole object. For example, becau se (you read because)
bottom-up processing
focusing on incoming sensory data. this is
audition
hearing
stroboscopic movement
in which an appearance of motion (or lack of motion) occurs when the stimulus is not viewed continuously but in distinct separate stages. Film reels work in this way - a film is comprised of many different separate stills that when viewed a certain way seem to have the appearance of motion. Another example is when wagon or bike wheels appear to go backwards when on film.
phi phenomenon
in which lights next to each other blinking on and off in succession appear to actually move. For example, a string of lights across a house appear to "run" even though you know it's just one light turning off and the one next to it turning on and so on down the line.
inner ear
innermost part of the ear, containing the cochlea, oval window, and basilar membrane
color constancy
is a Gestalt principle of perception that suggests that the context in which an object we are viewing appears in, influences the way we perceive the color of that object. an example. You are looking at a bowl of fruit, which has in it a bright red apple, bananas, grapes, and some mangos. If you saw only a small portion of the apple, but did not know that it was an apple, the color would appear to change a little as the light changed. However, once you know it is an apple, you will still perceive the color as bright red even when the light changes a little (really).
cochlea
is a bony, spiral-shaped, fluid-filled tube in the inner ear through which sound waves travel and trigger nerve impulse. Nerve impulses that send auditory signals to the brain for interpretation are sent from it.
nearsightedness
is a common vision condition in which you can see objects near to you clearly, but objects farther away are blurry
connectedness
is a sensation and perception term that refers to the perception of uniform or linked spots, lines, or areas as a single unit. When these these forms are linked together or uniform, they simply appear to form a single unit and seem to go together. For example, do you perceive the following as belonging together?: 0-0 0-0 0-0
telepathy
is communication sent or received directly from one mind to another without using speech, writing, body language, or other signals
touch
is really a collection of several senses, encompassing pressure, pain, cold, and warmth. Touch receptors are stimulated by mechanical, chemical, and thermal energy.
telekinesis
is the ability to move or change objects with the mind rather than with physical action. For example, a magician might claim to move an object across a table just by thinking about
perceptual constancy
is the ability to recognize that an object or organism has not changed (remained the same object or organism) even though other stimuli have changed. For example, when you go to a school reunion you will be able to recognize the other people from your class even though their physical characteristics may have changed such as increased weight, hair loss, etc.
taste
is the sensory experience of a substance that is put in our mouths. Our tongues are coated with taste buds which contain taste receptors cells. These cells react chemically with substances in our mouths to produce the sensation known as taste. Food molecules along with saliva interact with the taste receptor cells which tell us information about the substance. Humans have five recognized taste categories: sweet, bitter, salty, sour, and umani (savory).
shape constancy
is the tendency to perceive an object as having the same shape regardless of its orientation or the angle from which we view it. For example, when we look head-on at a rectangular picture frame hanging on the wall, it appears as a rectangle. If we walk off of to the side and look at the frame from an angle, we still recognize that it's in the shape of a rectangle, but really, from that angle, the image processed by our retina is that of a trapezoid.
cornea
is the transparent outer layer of the eye responsible for protection and vision. It bends the light that enters the eye which is responsible for the ability to focus on objects
difference threshold
let's say I asked you to put your hand out and in it I placed a pile of sand. Then, I add tiny amounts of sand to your hand and ask you to tell me when you notice any change in the overall weight. As soon as you can detect any change in the weight, that difference between the weight of the sand before I added that last bit of sand and the amount of sand after I added it, example of
vision stimulus input
light
proximity
means how close an object or person is physically to you. Someone sitting next to you on a bench is closer in proximity than a person sitting three rows away.
oval window
membrane-covered opening from the middle ear to the cochlea of the inner ear. through which sound vibrations of the stapes are transmitted.
difference threshold
minimum level of stimulation that a person can detect 50 percent of the time
sensorineural hearing loss (nerve deafness)
occur as a result of the loss of neural inputs (death of nerve cells) that connect the eardrum to the brain. This is the most common cause of hearing loss.
conduction hearing loss
occurs when there is a physical problem conducting sound waves through the ear mechanisms
afterimages
occurs when visually perceiving an image after you are not looking at the stimulus anymore. For example, if you look at the sun for a bit and then look away you can see the afterimage of the sun even though you are not looking at it anymore. A negative afterimage sensation of opposing colors that occurs after staring at a colored stimulus.
colorblindness
occurs when you are unable to see colorsin a normal way
optic nerve
one of the twelve cranial nerves, it's behind the eyeball and transmits visual information to the brain.
lightness/brightness constancy
our visual ability to perceive objects as having the same level of brightness even though the level of lighting changes
in audition, wavelength and frequency determines a sound's
perception of speech
psychophysics
railroad tracks look like they come closer in the distance, but we know their parallel. this is
place theory
refers to how sound is received and perceived by the human ear. It refers to how sound waves affect different areas of the tympanic membrane, or eardrum, to create the perception of different types of sounds. A similar effect can be seen by hitting a tamborine in different spots; hitting near the side gives a flatter sound that hitting it in the center.
visual capture
refers to our tendency to allow visual images to dominate our perception. For example, when we watch a movie in a theater, we tend to think that the voices we hear come from the moving images on the screen, rather than from the speakers that could be located all around the theater.
phantom limb
refers to physical sensations that are experienced by many amputees. This is where the brain continues to register physical sensations and/or pain signals from an arm or leg that no longer exists.
smell/ olfacoception
refers to the ability to perceive, identify and discriminate between smells. As part of a chemical receptive system odorant (scent) molecules are taken in by the nose and processed by olfactory (odor-detecting) receptors that are located in the sinus cavities. These odor signals are then processed by the olfactory bulb and transmitted to the brain.
in audition, amplitude or intensity determine's a sounds
volume (loudness)
gate control theory of pain
was developed by Melzack and Wall's who indicated that the spinal cord contains a type of neurological "gate" which opens and closes to either allow or block pain signals to travel to the brain. This gate does not actually open and close like the gate on a fence, but simply allows pain signals to pass onto the brain when they are traveling on the small nerve fibers, and does not allow pain signals to pass when they are traveling on the larger fibers. In this case, there doesn't really need to be anything physical to produce pain; you only need to have the small nerve fibers send signals onto the brain to feel pain. This is why, for example, some people who are missing a limb often indicate that they can feel the missing limb, have pain in the missing limb, etc.
color
wavelength or frequency determine a light's
priming
what we call it when exposure to some thing influences the behavior of an individual later on, without that individual being aware that the first thing is guiding their behavior to a certain extent.
parallel processing
when a person sees an object, they don't see just one thing, but rather many different aspects that together help the person identify the object as a whole. example of
signal detection theory
when you think your phone is ringing, but you check and no one was calling
signal detection theory
when you think your phone is ringing, but you check and no one was calling. example of
relative size
which allows you to determine how close objects are to an object of known size
similarity
which refers to the tendency for humans to group together objects or stimuli that seem similar to each other. For example, what do you see here: $$$$$ 88888 !!!!! Most people would say they see 5 dollar signs followed by 5 number 8's, and 5 exclamation points. But why not see this as 15 items that mean nothing together, or random symbols and numbers?
Farsightedness
which you can see distant objects clearly, but objects nearby may be blurry
transduction
your ears receive energy (sound waves) and transduce (or convert) this energy into neural messages that make their way to your brain and are processed as sounds. this is an example of
Weber's law formula
1. lights must differ in brightness by 8% 2. objects must differ in weight by 2% 3. tones must differ in frequency by .3%
retina
Contains sensory receptors that process visual information and sends it to the brain
sensory interaction
refers to the interaction of the senses to each other and how they influence each other. Taste and smell are two senses that work together. Food tastes more bland when a person has a stuffy nose and can't smell it properly. Some senses even overrule others if information seems contradictory. For instance, if someone hears speaking but the sounds of the speaking do not match the movements of the speaker's lips, the person will pay more attention to what they see. Vision dominates all the other senses.
relative motion
refers to the motion or speed of any object in respect to a particular point. For example, a ball thrown upward while in a moving object such as a bus, would be traveling the same speed with respect to the bus and would fall again in relation to that speed.
visual acuity
refers to the sharpness, clearness and focus of a person's vision. It is a measure of the eye's spatial resolution, or ability to perceive shapes and figures in a 3-dimensional setting. This is what is being checked when you take an eye test at a doctor's office or when applying for driver's license.
illusory contours
refers to the visual phenomenon or optical illusion of perceiving contours (curves, etc.) in an object where none exist. For example, this may occur when looking at a tree, or a telephone pole, from a distance and thinking that they see curves or bends in it that really don't exist.
continuity
refers to vision and is the tendency to create continuous patterns and perceive connected objects as uninterrupted.
signal detection theory
refers to whether or not we detect a stimulus, especially amidst background noise
audition stimulus input
sound waves
Young-Helmholtz trichromatic theory
states that within your eye are tiny cells that can receive waves of light and translate them into one of three colors: blue, green, and red.
top-down processing
using models, ideas, and expectations to interpret sensory information
opponent-process theory
suggested by Solomon where emotional reactions to a stimulus are followed by opposite emotional reactions. This theory may explain why stunt people enjoy their work. First the individual will feel intense anxiety before performing a stunt and then the person will receive an opposite reaction of relief after the stunt is completed. The theory also postulates that repeated exposure to the stimulus will cause less of an initial reaction and a stronger opposing reaction. This may explain why drugs, such as opiates, give diminishing returns after prolonged use yet the effects of withdraw become more intensified and unpleasant.
bottom-up processing
taking sensory information and then assembling and integrating it (body to brain)
human factors psychology
that studies how the human mind and body interacts with its tools and environmen
parallel processing
the ability of the brain to simultaneously process incoming stimuli of differing quality
clairvoyance
the ability to see or know things without actually perceiving them via the senses. It is a form of extrasensory perception (ESP). For example, psychic medium Teresa Caputo claims to communicate with the dead, and magician David Blaine can guess what card you have chosen out of a deck.
fovea
the central focal point on the retina in the eye around which the cones cluster. In fact, this has only cones around it, which are better for detecting fine detail. So, when trying to really see some fine detail or focus something, people tend to move the image onto this
absolute threshold
the minimum level of stimulus intensity needed to detect a stimulus half the time
gestalt theories of grouping
the observation that humans naturally perceive objects as organized patterns and objects
sensation
the process by which our sensory receptors & nervous system and receive and represent stimulus energies from our environment
perception
the process of organizing and interpreting sensory info enabling us to recognize meaningful objects and events
electromagnetic spectrum
the range of wavelengths of electromagnetic radiation from gamma rays (very short waves) to radio waves (very long waves).
auditory cortex
the section of the brain that processes information received through hearing. Located in the temporal lobe, a part of the cerebral cortex, it receives signals from the ears pertaining to pitch and volume of sound. For example, it registers sirens, door bells, telephone ringers, etc. , any sound that is designed to gain attention.
middle ear
the space between the eardrum and the inner ear, where three tiny bones (also known as ossicles) are located
psychophysics
the study of how physical stimuli are translated into the psychological experience (how do we process the things we see and hear around us)
frequency theory
theory of how we hear sounds states that there are pulses that travel up the auditory nerve, carrying the information about sound to the brain for processing, and that the rate of this pulse matched the frequency of whatever tone you are hearing exactly. We thus hear the tone because the pulse traveling up the auditory nerve matches the actual tone. Essentially, we are getting a copy of the real sound.
sensory adaptation
to detect novelty in our surroundings, our senses tune out a constant stimulus
transduction
transforming this cell stimulation into neural impulses
figure-ground
two main visual components necessary for a person to see an object properly;the object and the background or surroundings in which the object occurs. Thus, when you look at a picture on a wall, the picture is the figure and you can distinguish it clearly from its surroundings, the wall (ground).