Psyc 351 Study Guide Test #2 Pt.1
perceptual capacity
The idea that a person has a given capacity that he/she can use to carry out perceptual tasks
Reichardt detector
But vision is not solely based on what appears on the retina! In order to full consider motion perception, we must also understand the neural signals that travel from the eye to the brain. -Werner Reichert (1969) proposed the neural circuit called the
akinetopsia
Motion blindness -A condition in which motion is difficult or impossible to perceive motion -L.M., a 43 year old woman, was unable to perceive motion following a stroke
optic flow
Movement of objects in a scene relative to an observer
neural synchrony, synchrony
-Attention increases ____ _______, otherwise known as coherence --_______: When neurons fire together
trichromatic theory
-Color vision depends on the activity of three different receptors (red, green, and blue cones) -Supported by color matching experiment --Yellow made from pure yellow light source cannot be differentiated from the combination of red and green. -Supported by the fact that we have three types of cones in our eyes. -The evidence came from the metamer, or color matching experiment, a participant is first presented with colors on the left that came from a monochromatic light source
80, twice, mental resources
-In __% of crashes, the driver was inattentive in some way 3 seconds beforehand. -In 67% of near crashes the same is true. -One of the most distracting activities is pushing buttons on a cell phone. -Strayer and Johnston (2001) gave subjects a simulated driving task that required them to apply the brakes as quickly as possible to a red light. -People where were talking on a cell phone missed _____ as many red lights as when they weren't talking on the phone. -Talking on the phone uses ____ _______ that would otherwise be used for driving a car.
hippocampus, place, grid
-John O'Keefe --Recorded from neurons in the _________—an area of the brain important for memory formation. --_____ Cells: Individual neurons fire when the rat is in specific place within the box --Different cells prefer different locations—Place field -____ Cells: Neurons near the entorhinal cortex which fire in response to the rat being in one of several positions, in a grid-like pattern. Provide information about direction of movement -Taxi Driver vs. Bus Driver—Hippocampal Volume
aperture problem
-Neurons can only perceive one direction of movement in their receptive field. -Viewing a small portion of a large stimulus can lead to misleading information.
mirror neurons
-Neurons that respond both when observing someone perform an action, and when performing an action. -May help us to understand emotional facial expressions and gestures from others. -May play an important role in social interaction
Corollary Discharge theory
-Takes into account: --How the image is moving on the retina --How the eye is moving -a) Image Displacement Signal (IDS): When an image moves across receptors on the retina -b) Corollary Discharge Signal (CDS): A copy of the motor signal from the eye muscles that is sent to the brain.
transcranial magnetic stimulation
-Temporarily disrupts firing of neurons via a series of electromagnetic pulses. -If a behavior is disrupted by pulses to a specific area, this implies that this brain area is involved in behavior. -Why does TMS work to disrupt neural activity? Sodium generates the action potential making the Net charge more positive
red green, blue yellow, complete
-___-_____ Colorblindness: Due to loss or limited function of red cone (protan) or green cone (deutan) photopigments. Protanomaly—Abnormal red cone photopigment Protanopia—No working red cone cells Deuteranomaly—Abnormal green cone photopigment. Most common form of colorblindness X-linked disorder affecting 5% of males. Deuteranopia—No working green cone cells -____-_____ Colorblindness Tritanomaly—Limited blue cone cells Tritanopia—Lack of blue cone cells -_______ Colorblindness Cone monochromacy—Two of Three cone cells fail. Achromatopsia—No cone cells have functional photopigments.
overt, covert
-_____ Attention: Looking directly at the attended object -______ Attention: Attention without looking --Allows you to monitor the actions of someone near you without staring --Important for many sports --Important for sight-reading in music
oculomotor, monocular, binocular
-________: accommodation, convergence -_________: static dynamic -_______: disparity
parahippocampal, hometown, mazes, cognitive map
-___________ Gyrus—Brain structure involved in navigation -Topographical Agnosia: Inability to recognize landmarks in real-world environments --F.G., A man with damage to parahippocampal gyrus had difficulty navigating in a new environment using landmarks. --Interestingly, F.G. could navigate in his _______ using signs and printed building names. -Edward Tolman studied how rats learn to navigate in _____. --Instead of simply turning right every time regardless of where they are, rats use spatial and other cues in order to create a ______ ___ of the layout of the maze.
hues
-chromatic colors such as blue, green and red occur when some wavelengths are reflected more than others, a process called selective reflection -the wavelength, or set of wavelengths, that bounce off an object and into our eyes determine the ___ that we perceive
corollary discharge signal
A copy of the motor signal from the eye muscles that is sent to the brain.
balint's syndrome
A disorder caused by damage to the parietal lobe. --Inability to focus and shift attention when multiple objects are present in a scene. --Inability to perceive the visual field as a whole (simultagnosia) --Difficulty fixating on objects --Inability to move hand to specific object (optic ataxia)
visuomotor grip cells
A neuron that responds when a monkey sees a specific object and also responds when a monkey forms its hand to grasp the same object
comparator
A structure or mechanism in the brain that receives both the IDS and CDS.
end, hypercomplex
Aperture problem: solution one -A neuron can use information about the ___ of a moving object (e.g. the tip of a pencil) in order to determine the direction of motion -What kind of neurons in striate cortex signal this information? ________ cell
combine, orientation, striate cortex
Aperture problem: solution two -Pool or ______ responses from other neurons -Evidence: --Activity of neurons in the monkey MT are recorded while the monkey looks at moving oriented lines (e.g. a pole or pencil) --Initial response of MT neurons (about 70 ms after stimulus onset) is determined by _______ of the bar --140 ms after presentation of moving bars, neurons began responding to actual direction in which bars were moving. --Thus, MT neurons receive signals from other neurons in the _____ _____ and combine these signals to determine the actual direction of motion.
shortest path constraint
Apparent movement occurs along the shortest path between two stimuli. --The longer the delay between the second picture, the more likely a longer path of motion is perceived. -When objects such as boards are used as stimuli, the likelihood of perceiving movement along a longer path does not increase for shorter inter-stimulus-intervals.
deletion, accretion
As you move your head, your left hand appears to cover your right hand. This covering of the farther right hand is _____. if you then move your head back to the right, the nearer hand moves back and uncovers the right hand. This uncovering of the far hand is ______
ishihara plates
Dalton's descriptions of his abnormal color perceptions led to the early use of the term Daltonism to describe color deficiency. We now know that there are a number of different types of color deficiency. This has been demonstrated by color vision tests, which are called _______ _____
implied motion
Despite lack of real or apparent motion, brain perceives this image as a "freeze frame".
head direction cells
Fire depending on the direction the animal is facing
speeding, more quickly, details
How does paying attention to a stimulus in the environment change the way that the visual system processes that stimulus? -________ Responses to Locations -Spatial Attention: Paying attention to a specific spatial location --Does paying attention to a location improve a person's ability to respond to stimuli? -Participants react ____ _____ to valid trials than to invalid trials. -Posner interpreted this as more effective information processing at the place where attention is directed. -Attention speeds responses to objects --Attending to objects can enhance our response to them --When attention is directed to one part of an object, the enhancing effect of attention spreads to other parts of the object. -Attention can enhance the _____ of an object
topographical agnosia
Inability to recognize landmarks in real-world environments --F.G., A man with damage to parahippocampal gyrus had difficulty navigating in a new environment using landmarks. --Interestingly, F.G. could navigate in his hometown using signs and printed building names
place cells
Individual neurons fire when the rat is in specific place within the box ---Different cells prefer different locations—Place field
habituation
Infants are more likely to look at a novel stimulus. Thus, we can familiarize an infant with one stimulus and present another
affordances
Information indicating how an object can be used. --This is what the object offers the animal (e.g. what it provides or furnishes)
load theory of attention
Involves two concepts: --Perceptual Capacity: The idea that a person has a given capacity that he/she can use to carry out perceptual tasks --Perceptual Load: The amount of a person's perceptual ability needed to carry out a specific task.
grid cells
Neurons near the entorhinal cortex which fire in response to the rat being in one of several positions, in a grid-like pattern
mirror neurons
Neurons that respond both when observing someone perform an action, and when performing an action. --It has been proposed that mirror neurons respond to the intention behind what is happening --May help us to understand emotional facial expressions and gestures from others.
real motion
Observing an object which is moving in the environment
spatial attention
Paying attention to a specific spatial location --Does paying attention to a location improve a person's ability to respond to stimuli? --Benefit of attention
apparent motion
Perceiving motion where there is none
saccadic eye movement
Rapid jerking movement from one fixation to the next. --When you are viewing an object, you move your eyes ~3 times per second
color solid
Since we now have a third dimension of color, we can no longer represent all the possible colors in a 2 dimensional wheel. That is why, to represent all the possible colors, we need a ____ ____
attentional capture
Stimulus properties grab a person's attention automatically ---Sudden movement ---Loud sounds ---Angry faces/voices
optic array
Structure created by surfaces, textures, and contours in the environment. --J.J. Gibson, the founder of the ecological approach to perception, proposed a solution to the problem of how we are able to perceive motion.
inattentional blindness
Subjects can be unaware of clearly visible stimuli if they aren't directing attention to them.
perceptual load
The amount of a person's perceptual ability needed to carry out a specific task.
representational momentum
The idea that motion depicted in a picture continues in an observer's mind. -Like in the waterfall illusion, viewing images of implied motion decreases the activity of neurons in the MT and MST cortex to motion in the implied direction, thus subjects are more likely to perceive objects in their environment as moving in an opposite direction
ecological validity
The idea that the thing you are measuring are as close to its natural environment as possible. E.g. We do not simply act as passive observers in our environment, viewing static images of faces or objects. Our environment is constantly moving and changing, thus it is difficult to get good ecological validity in psychological experiments which measure perception—one question that researchers are always asking is how to get the behavior to be as close to what it would be in the natural environment as possible—and that means creating a more authentic experimental environment
noncorresponding points
The images of objects not on the horopter fall on _________ _____
color constancy
The sweater is green but when we consider the interaction between the illumination and the properties of the sweater, we can appreciate that your perception of the sweater as green, both outside and inside, represents a remarkable achievement of the visual system. We perceive the colors of objects as being relatively constant even under changing illumination
focus of expansion
There is no flow at the destination point—meaning that the destination point does not appear to move
binding problem
This describes the question of how an object's individual features come together to form a uniform percept. --When a red ball rolls by, it activates: --Inferotemporal Cortex: Senses shape --Middle Temporal Cortex: Senses movement --V2: Senses Depth --V4: (an associative region of visual cortex) Senses color
feature integration theory
This theory attempts to solve the binding problem via a two-stage model of attention: 1) Preattentive Stage Automatic, unconscious, effortless Features of objects are analyzed by separate areas of the brain 2) Focused Attention Stage Features from stage one are linked together Person becomes consciously aware of red ball rolling to the right
saturation
We can create even more colors by changing the intensity of the light to make colors brighter or dimmer, or by adding white to change a color's ________
familiar size
We use the cue of _______ ____ when we judge distance based on our prior knowledge of the sizes of objects
horopter
Whatever a person is looking at directly falls on corresponding points, and some other objects that fall on corresponding points are located on a surface called the _______
self produced information
When a person uses information from a movement that they make in order to guide further movement. -E.g. If you drive a car, you are using self-produced information in order to guide further movement. If you get into a particular lane and the pavement is very bumpy and uneven or makes a terrible noise, you will likely get into the other lane or be eager to change the road that you are on. -Professional gymnasts perform backflips better with their eyes open. They are able to adjust for their trajectory by making muscle movements that make sense with the visual information they are receiving
image displacement signal
When an image moves across receptors on the retina
disturbance in the optic array
When someone or something moves, they cover and uncover objects that are stationary in the background—this disturbance provides information about the direction and speed of motion.
illusory motion
When stimuli in different locations are alternated with the correct timing, an observer perceives the stimulus as moving back and forth. E.g. flip book animation
salience, valence, less, more
_____: -important (of very high positive or negative valence) -Items that are more salient tend to be initial fixation points e.g. Really dark image is ___ salient. Bright image is ____ salient
decision point, non decision point
_______ _____ Landmarks: Landmarks where you must make turn or change in direction. ___-______ _____ Landmarks: Landmarks that provide no additional information about how to navigate
dual task procedure
a procedure in experimental (neuro)psychology that requires an individual to perform two tasks simultaneously, in order to compare performance with single-task conditions. When performance scores on one and/or both tasks are lower when they are done simultaneously compared to separately, these two tasks interfere with each other, and it is assumed that both tasks compete for the same class of information processing resources in the brain.
crossed disparity
happens for objects that are closer to you, which can remember because to see them you have to cross your eyes
uncrossed disparity
images that are farther away from you than the horopter also don't land on corresponding points on the retina. But when images are farther away, they exhibit this
color matching
observers adjusted the amounts of three different wavelengths of light mixed together in a "comparison field" until the color of this mixture matched the color of a single wavelength in a "test field"
convergence
occurs when a person looks at something that is very close
motion parallax
occurs when, as we move, nearby objects appear to glide rapidly past us, but more distant objects appear to move more slowly
corresponding points
points on the retina that overlap if the eyes are superimposed on each other
task irrelevant stimuli
stimuli that don't provide information relevant to the task with which we are involved. Examples such as the computer pop-up or the billboard are distracting " ", which can potentially decrease our performance of a task
cerebral achromatopsia
the idea of an area specialized for color was put forth by Semir Zeki based on his finding of many neurons in a visual area outside of the monkey's visual receiving area called V4 that responded to color, and on the phenomenon of _____ ________. A condition caused by damage to the brain like that experienced by Mr. I, who suffered an automobile accident that left his perception of form and motion intact but caused him to lose his ability to see color
steopsis
the impression of depth that results from information provided by binocular disparity
opponency theory
the intuition that illusions like the flag one gave Herring was that instead of there being 3 primary colors, there are four, in pairs.
metamerism
the lights in the two fields are physically different but they are perceptually identical. This situation, in which two physically different stimuli are perceptually identical
perceptual completion
the perception of an object as extending behind occluding objects, such as the horizontal boards that partially block the view of the three men
subtractive color theory
the reason blue paint looks blue is that it absorbs all wavelengths that hit it except for the blue ones, leaving only the blue ones to bounce off it and back to our eyeballs
dynamic monocular cues
those you DO have to be moving to use
precuing
to determine whether presenting a cue indicating where a test stimulus will appear enhances the processing of the test stimulus
additive color theory
when two lights are mixed, the wavelengths of both lights are perceived. We perceive a color that is basically "in the middle of the two colors. How your computer monitor, smart phone, tablet create color
relative size
when two objects of equal size, the one that is farther away will take up less of your field of view than the one that is closer
static monocular cues
work with only one eye. They include accomodation, pictorial cues, which are sources of depth information in a two-dimensional picture; and movement based cues, which are sources of depth information created by movement. Those that you don't have to be moving to use
accomodation
your brain is aware, at any given moment, of how flexed your lens muscles are, and you can use this information to guess how far away whatever you are looking at is