Topic 7 all Flashcards
What is Overt attention?
where we are looking at with out eyes
What do overt shifts of attention require?
eye movements
What are the three components of overt attention?
Saccades
Fixation
Smooth pursuit
What are saccades?
Rapid, ballistic movements from one place to another
What are fixations?
Short pauses on points of interest
What is smooth pursuit?
slower, smooth movements tracking a moving object
When are saccades and fixations used?
When looking at a static object
What is overt attention studied using?
eye tracker
Describe the study on overt attention?
Brought people in and made them wear an eye trackers
then gave them certain tasks for an image
Ex: give the ages of the people in the painting
What does attention depend on according to the painting study on overt attention?
painting itself - bottom up
goals that they were presneted with
What are the two things that direct our attention?
visual salience and cognitive factors
What are the characteristics of visual salience?
Bottom-up
exogenous - outside the mind
In the environment
reflexive - hard not to attend
automatic
What are the characteristics of cognitive factors?
top-down
endogenous
in the mind
voluntary - choosing to follow instructions
intentional
What is visual salience?
The distinct subjective perceptual quality which makes some items in the world stand out from their neighbours and immediately grad our attention
What are the four sources of salience?
Contrast
Colour
orientation
movement
What do saliency maps show?
Typically, no single feature stands out, so saliency is based on a combination of distinct feature dimensions
what parts of an image are salient
What is there a strong correlation between with saliency maps?
where people fixate on a image and saliency maps
What are the three cognitive factors that direct attention?
Scene schema
Task and action plan
Intentions and goals
What is scene schema?
knowledge about what is contained in a typical scene
What do scene schemas help with?
help guide fixations from one areas of a scene to another
What did the study on scene schemas find?
objects that violate the schema attract more attention
it is not based on low-level characteristics like colour or lightness
How are task and action plans cognitive factors?
eye movements precede motor actions by a fraction of a second
attention is the leading edge
What is the study on task and action plans?
track eye movements while making a sandwich
How are intentions and goals cognitive factors?
the purpose for which an observer views a scene influences where they look
What is the study on intentions and goals?
What participant was asked to derive from the scene influenced attentions - painting study and eye tracking
What are the two benefits of attention?
speed and apparent contrast
What is the study that shows attention speeds responding to locations?
Posner spatial cueing task
What is the posner task?
Spatial cueing task
Maintain central fixation
Spatial cue tells you where to attend - valid 80% of the time
stimulus appears on the right or left (50%)
And you press a key to indicate the stimulus
What does the posner task show?
50 ms faster at responding to valid cues
Describe the study on attention speeds responding to objects
Two rectangles
cue on the end of object:
valid
invalid, same object
invalid other object
stimulus on the end of object and you hit a key
What did the task on attention speeds responding to objects find?
attention is based on objects too
attention spreads to entire object
response to cued location was fastest, then invalid location but same object
Explain the study on attention and apparent contrast
maintain fixation
cue flashed on left or right
stimuli presented
indicate which one has the higher contrast
What did the study on attention and apparent contrast find?
attention causes a weaker contrast to appear as if it were stronger
attention increases apparent contrast
when the grating on the left was cued (lower contrast), both gratings appeared to have the same contrast
What is the third benefit of attention?
binding of visual features
Describe the study on attention and binding of visual features. What are the two task?
rapidly flashed a display on the screen, followed by a visual mask
Task 1: report numbers
Task 2: report objects
What did the task on attention and binding of visual features find when participants were asked to attend to numbers?
participants reported combinations of features from different stimuli (i.e red circle) - illusory conjunctions
they saw the features but couldn’t combine them
Why do illusory conjuctions occur?
features are free-floating since attention was focused on numbers
What did the task on attention and binding of visual features find when participants were asked to attend to objects?
participants show fewer illusory conjuctions due to attention
What is the theory that describes attention binding visual features?
feature integration theory
What does feature integration theory state?
attention is required to bind different features into consciously experienced whole
What are the steps of feature integration theory?
preattentive stage happens automatically
What are the two stages of feature integration theory?
Preattentive stage and focused attentive stage
What are the characteristics of the preattentive stage?
automatic
no effort or attention
unaware of process
object analyzed into features
What are the characteristics of the focused attention stage?
attention plays a key role
feature are combined/bound into an object
What parts of the visual scene does the preattentive stage analyze?
the whole visual display in parallel
What are the costs of attention?
inattentional blindness, change blindness, cognitive load
What is the monkey business illusion?
You are looking for the gorilla so you missed the colour of the curtain change
What is inattentional blindness?
we can be unaware of clearly visible stimuli if we aren’t directing our attention to them
What is the study on inattentional blindness?
asked to judge whether the horizontal or vertical line is longer in a cross
A shape shows up on occasion and many people failed to notice it
What is change blindness?
changes in a picture or scene between viewings can go unnoticed if not attended to
if you get rid of the noise it is very obvious
What is the example of change blindness
image flickers back and forth but we fail to notice line or shadow changing
What is the load theory of attention?
We only have so much attention to go around
For low-load tasks we can notice other things because it doesn’t take up much attention
High-load tasks take up a lot of attention to we fail to notice other things
What was the question of the flanker task?
can participants focus attention on detecting the target so that the distractors (flankers) will not affect their performance?
What is the flanker task?
show participants letters and they have to respond to the middle
But there are distractors on the outside
Respond left for A and B and right for C and D
What is an example of a compatible, neutral and incompatible trial for the flanker task?
BAB - compatible
XAX - neutral
CAC - incompatible
What did the results of the flanker task show on the graph
responded fastest for compatible, then neutral, then incompatible
What is the flanker compatibility effect between?
difference in time between the incompatible and compatible trial
How does the flanker compatibility effect relate to the load theory for the neutral stimulus?
still have lots of attention left
What is the second version of the flanker compatibility task? What are the low-load and high-load conditions? Describe the compatible and incompatible conditions for both?
Respond left for X and right for N
Low-load - stimulus in a bunch of Os
High load - stimulus in a bunch of random letters
LL:
Compatible - X presented as a flanker and X presented as the cue
incompatible - N presented as the flanker and X presented as the cue
HL:
Compatible - X presented as a flanker and X presented as the cue
incompatible - N presented as the flanker and X presented as the cue
What were the results of the second flanker compatibility task?
Flanker compatibility effect was observed in the low-load condition
Flanker compatibility effect goes away for the highload condition - nothing left to get distracted because all of the load is being used by the primary task
What did the second flanker compatibility test show (overall lesson)?
high perceptual load reduces distraction
What did this study do intially? What did they do after?
Created a retinotopic map of primary visual cortex - map of visual field as presented in cortex
Get participants to fixate in the center and attend to 1 of 18 locations
observe change in brain activity due to attention
What did the study on brain activity and attention show?
Attention to a spatial location increases neural activity in brain areas representing that location
What did the study on the face and the house do?
Told to attend to either the face or the house and recorded activation in the FFA and the PPA
What did the FFA show when told to attend to the face vs the house?
greater activation when attending to the face
What did the PPA show when told to attend to the house instead of the face?
more activation to the house than the face
What did the results of the study on the face/house show?
Attention to an object increases neural activity in brain areas representing that object - higher level objects attention not just location
Describe the study where a single cell recording in neuron of monkey with receptive field at location of peripheral light
monkey trained to fixate eyes on fixation light when peripheral light was flashed
Two conditions:
Fixation only: release bar when fixation light is dimmed - look and attend to fixation light only
Fixation and attention: look at fixation light but attend to perpheral light
release bar when peripheral light is dimmed
What did the single cell response of a neuron in V1 with receptive field in the periphery show?
Single neuron activity increased when monkey payed attention to a spatial location - attention boosted response when attending to periphery
Describe the study on neural synchronization
recording local field potentials on the surface of the brain
Present two visual stimuli: 1 and 2
give animal a cue about which circle to attend to - release bar when blue stimulus changes
What areas were activated for each stimulus in the neural synchronization study?
Stimulus 1 - activates A (V1A) and C (V4)
Stimulus 2 - activates B (V1B and C (v4)
V4 receptive field is large enough that it responds to both
What did the brain recordings for the synchronization study show?
When the person did not attend to stimulus 1, areas A and C did not have synchronized activation
When they did attend to stimulus 1 - areas A and C became synchronized
What were the results of the study on neural synchronization?
attention to stimulus increases synchronization between brain areas representing that stimulus
What could synchronization be a neural mechanism for?
binding features maybe - attention causes us to bind features together and also causes brain synchronization
Describe the study on attention and receptive fields?
record MT neuron with indicated receptive field
eyes at fixation and attend to S1, S2, S3 based on cue
2 of the cues are located in the receptive field
What were the results of the study on attention and receptive field
Attending to the stimuli in the neurons RF caused the receptive field to shift towards the stimulus
If the stimulus was outside the receptive field then the receptive field stayed in its normal spot
What was the conclusion of the study on attention and receptive fields?
attention to a stimulus within a receptive field can modify the location of the receptive field
What is the neural basis of attention?
Increased neural activity in brain areas representing attended location and objects
Increased synchronization of neural activity between brain areas representing attended locations and objects
Modification of receptive field location folllow attentional focus
What are magicians?
artists of attention and awareness
Name all the magic effects
Appearance
Vanish
Restoration
Penetration
Transformation
Extraordinary feats
Telekinesis -
Extrasensory perception (ESP)
What is telekinesis?
magical levitation or animation of an object
What is Extrasensory perception (ESP)?
clairvoyance, telephathy, precognition, mental control etc
What is needed to be a magic pickpocketer?
follow the attention and manipulate peoples attention
