1
Q
What is attention?
A
The ability to focus on specific stimuli or locations in our environment
2
Q
What are the different types of attention?
A
- Selective Attention
- Divided Attention
- Overt Attention
- Covert Attention
- Exogenous Attention
3
Q
Define Attentional capture
A
- a rapid shifting of attention
- usually caused by a stimulus such as load noise, bright light or sudden movement
4
Q
Define Distraction.
A
one stimulus interfering with the processing of another stimulus
5
Q
What is filtering?
A
Dumping away unwanted information
6
Q
What are distractions?
A
One stimulus interfering with the processing of another stimulus?
7
Q
Define Selective Attention.
A
- attending to one thing while ignoring others
- we do not attend to a large fraction of info in the environ
- we filter out some info and promote other info for further processing
- different models of SA proposed that the attention filter comes in different periods of processing
8
Q
What are the main models of Selective Attention?
A
- Broadbent’s filter model of attention
- early selection model - Treisman’s Attenuation theory
- intermediate selection model - McKay’s late seletction model
- late selection model
9
Q
What are the concepts related to Broadbent’s filter model of attention?
A
Dichotic task:
- presenting different stimuli to left and right ears
Shadowing:
- procedure of repeating the words they heard
Cocktail party effect:
- the ability to focus on one stimulus while filtering out other stimuli
- this is because at noisy parties people are able to focus on what one person is saying
- this is despite there are many conversations happening at the same time
10
Q
Explain Broadbent’s filter model of attention.
A
- designed to explain the results by Colin Cherry (1953)
- used dichotic listening to study attention
- parti had to focus on the message in one ear (attended ear)
- and then repeat what he heard out loud (this is known as shadowing)
- RESULTS:
- they could easily shadow a spoken message (by attended ear)
- they could also report whether the unattended message was spoken by male/ female, sound or noise
- BUT they couldnt report what was being said in unattended ear (language, words, regardless of repetition)
- this is known as the cocktail party effect
Broadbent’s theory:
- Sensory memory holds all of the info for a frac of second
- it then gets transferred to the filter - Filter identifies the msg being attended
- based on physical characteristics
- eg. tone, pitch, accent
- then lets attended msg pass through
- ALL other messages are filtered out
- this is to prevent overloading of the limited capacity of filter - Detector processes the info from attended msg
- to determine higher lvl characteristics like meaning
- becos only imp, attended msg has been let thru, detector processes ALL of it - The output of detector is STM
- holds the info for 10-15 secs
- then transfer info to LTM
11
Q
Explain the rationale behind Treisman’s Attenuation theory.
A
- Moray did a dichotic listening task with partis
- dichotic task + shadowing
- but when he presented parti’s name in their unattended ear, 1/3 detected it
- this was in contradiction to Broadbent’s theory (it is supposed to only let one msg thru, based on phy charac!!!)
- ALSO, Treisman conducted a Dear Aunt Jane experi
- attended ear received message: dear 7 jane
- unattended ear: 9 aunt 6
- however rather than reporting dear 7 jane, they reported dear aunt jane
- this means that their attention jumped from one ear to the other
- this means they were taking in the MEANING of the words into account
- hence Treisman made a modi of Broadbent’s model
The Attenuator- analyzes the incoming msg in terms of 1) phy charac, 2) language 3) meaning
Treisman’s Attenuation theory:
- Attended and unattended message are identified
- Both pass through the attenuator
- Attenuated msg goes thru at full speed
- Unattended msg is attenuated (it is present, but weaker then AM)
- Some of the UM gets through the attenuator
- this is why it is called the leaky filter model
- the final output is determined here - Message is analyzed by the dictionary unit
- DU contains words stored in memory
- each word has a threshold for being activated
- threshold: smallest signal strength that can barely be activated
ACCORD to Treisman, words that are common/ imp (our names) have low thresholds so a weak signal in the unattended channel can activate the word (we can hear our name from across the room). Uncommon words have higher thresholds.
HENCE IN THIS MODEL, THE ATTENDED MSG GETS THRU ALONGSIDE SOME PARTS OF THE WEAKER, UNATTENDED MESSAGE.
12
Q
Explain the rationale behind McKay’s late selection model.
A
Late selection model- selection of stimuli for final processing does not occur until after information has been analyzed for meaning. They disagreed with Treisman.
Donald McKay’s experi:
- made parti listen to an ambigous senence
- ‘they were throwing stones at the bank’
- this could be interpreted as a riverbank or a financial institution
- this ambi sentence was presented to attended ear
- meanwhile unattended ear either heard ‘river’ or ‘money’
- after hearing a no. of ambi sentences, they were presented with pairs of sentences
1. they threw stones toward the side of the river yesterday
2. they threw stones at the savings and loan association yesterday - they were then asked to indicate which had closest meaning
- RESULTS: if they heard the biasing word ‘money’ they were likely to pick 2., if not 1.
- McKay proposed that the meaning of ‘river’ or ‘money’ was affecting the partis judgements, the words must have been processed to the level of meaning tho it was unattended
- HENCE, they proposed most of the incoming info is processed to the level of meaning BEFORE the msg to be fur ther processed IS SELECTED.
13
Q
Describe Treisman and Geffen (1967)’s experiment
A
- they wanted to compare the attenutation vs late selection theory
- in shadowing task, they were asked to tap whenever they heard a target word fr either ear
- prediction: AT: detection shd be better in attended ear
- prediction: LST: detection should be equal in both ears
- RESULTS: show that 87% was detected in the attended ear and 8% in unattended ear
14
Q
What is Processing Capacity and Perceptual Load? Give an eg. which can demonstrate this.
A
Processing capacity:
- amount of info people can handle
- sets a limit on their ability to process incoming info
Perceptual Load:
- related to the difficulty of a task
- some tasks (easy/ well practiced ones) have low perceptual loads
Foster and Lavie (2008)
- partis had to respond as quickly when they identified a target as X or N
- they pressed one key when they saw X and another key when they saw N
- the task becomes harder when X or N are surrounded by different letters as compared to only small ‘o’s earlier.
- RESULTS:
- they take longer RT in the hard task
- however, when a unrelated cartoon is shown, responding slows for the easy task > hard task
15
Q
What are low load tasks and high load task?
A
Low load tasks:
- use up only a small amount of a person’s processing capacity
High load tasks:
- tasks that are difficult/ not well practised
- uses more of a person’s processing capacity
16
Q
Explain the Load Theory of Attention, and an eg. that can explain it.
A
LTOA:
- low load tasks that use few cognitive resources may leave resources avail for processing unattended task- irrelevant stimuli
- WHEREAS, high load tasks that use all of a person’s cognitive resources don’t leave any resources to process unattended task irrelevant stimuli
- the ability to ignore task irrelevant stimuli is a function not only of the load of task but also HOW POWERFUL the task irrelevant stimulus is
Stroop Effect Experiment;
- quickly name the color of ink used to print each of the shapes
- then repeat it for the bottom picture where the words of colors are printed in a diff color than the word itself
- this is usually harder as the names of the words cause a competing response
- this slows responding to the target (the color of the ink)
- here, the task irrelevant stimuli is extremely POWERFUL
- cause reading words is highly practiced and it is so automatic that it is difficult not to read them
17
Q
What is Point of Selectivity?
A
- Attention is limited, and its selective
- You may not always be attending to the right thing
18
Q
What is Fixation?
A
when you briefly pause to look at something
19
Q
What is Saccadic eye movement?
A
- when you move your eyes to observe another face
- a rapid, jerky movement from one fixation to the next
20
Q
What is Overt Attention and its related concepts?
A
Overt Attention:
- Shifting attention from one place to another by moving the eyes
- We can see attentional shifts by observing where the eyes are looking at
Bottom up determinants of eye movements:
- Stimulus salience: areas that stand out and capture attention
- The physical properties of stimulus (color, contrast, movement)
Top down determinants of eye movements:
- Scene schema: knowledge about what is contained in a typical scene
- It helps to guide fixations from one area of a scene to another
- People look longer at things that seem out of place in a scene, this is cause their attention is affected by knowledge of what is found in the scene
- eye movements are determined by this task
21
Q
What is Covert Attention?
A
Covert Attention:
- shifting attention while keeping the eye still
- this is cause attentional shift cant be seen by observing the person
- this involves shifting attention with the mind (when you are paying attention to smth but look out the corner of your eye while still looking straight)
22
Q
What are the related concepts to Covert Attention?
A
Precueing:
- directing attention without moving the eyes
- partis respond faster to a light at an expected location than at a unexpected location
Posner (1978) Precueing experi:
- determine whether presenting a cue indicating where a test stimulus will appear enhances the processing of the target stimulus
- partis saw an arrow cue indicating on which side of the display they shd focus their attention on
- task is to press a key rapidly as possible when target square was presented at the side
- on 80% of trials, the cue arrow directed partis attention to the side when the target square appeared (valid trials)
- on 20% of the trials, the arrow directed the partis attention away from where the target was supposed to appear (invalid trials)
- RESULTS: partis reacted to the square more rapidly when their attention was focused on the location where the signal was going to appear
- Posner interpreted this result as showing that info processing is more effective at the place where attention is directed
- this gave rise to the idea that attention is like a spotlight or zoom lens that improves processing when directed towards a parti location
23
Q
What is object based and location based?
A
Location based:
- moving attention from one place to another
Object based:
- attention being directed to one place on an object
24
Q
Describe Egly’s (1994) bar precueing experiment.
A
- cue signal appeared on one place in the display
- bar magnets experi
- then a cue is turned off and a target is flashed at one of the 4 possible locations A,B,C,D
- partis task is to press a button when the target was presented anywhere on the display
- RESULTS: respondeed most rapidly when target was at A where the cue had bene presented
- but they responded even more rapidly when the target was presented at B than at C
- B’s advantage is that is located within the object that was receiving the parti’s attention
25
What is Same object advantage?
the faster the responding that occurs when enhancement spreads within an object
26
What is Divided Attention and an eg. to describe it.
Divided attention:
- Paying attention to more than one thing at a time
Shiffrin and Schneider (1977):
- carry out 2 tasks simultaneously
- 1) hold info abt target stimuli in memory
- 2) paying attention to a series of distractor stimuli to determine whether one of the target stim is present among these distractor stim
- followed by rapid presentation of 20 test frames (each contained distractors)
- on half the trials, one of the frames contained a target stim from memory set
- a new mem set was presented on each trial (the target changes from trial to trial)
- RESULTS:
- beginn: perf was 55% correct, took 900 trials to reach 90%
- after 600, it became automatic
- practice made it possible for partis to divide attention and deal with target and test items simul
- led to automatic processing
27
What is Automatic Processing?
1) occurs without intention and happens automatically
| 2) at a cost of some of a person's cognitive resources only
28
Define Exogenous attention.
- The redirection of attention toward an unexpected stimulus
- sudden, high intensity stimuli in the periphery
- eg. loud thunderstorm outside
29
What is Inattentional blindness and Change Detection?
IB:
- when people are unaware of clearly visible stimuli
- if they arent directing their attention to them
- usually a stim that is not attended is ot perceived, even tho it is clearly visible
- gorilla in ball passing video
CD:
- lack of attention can affect perception using CD
- one pic is presented followed by another
- the task is to determine what the differences are betw them
30
What is Binding?
- the process by which features (color, form, motion) are combined
- to create our perception of a coherent obj
- this leads to binding prob where
- we dont know how our brain binds all of these features to create a coherent perception
31
Explain the Feature Integration Theory (FIT).
Preattentive Stage:
- occurs bef we focus attention on an obj
- this stage is automatic, unconscious, effortless
- here features are analyzed independently in separate areas of the brain
- not yet associated with a specific obj
- eg. rolling ball -> color, form, rightward movement are viewed separately
Focused attention stage:
- second stage
- attention is focused on an obj
- the independent features are combined
- this causes the observer to become consciously aware of the rolling red ball
Object -> preventive stage -> focused attention stage -> perception
32
Explain some evidence for the FIT.
Treisman and Schimdt
- FIT approach involves mostly bottom up processing becos knowledge is usually not involved
- but sometimes top down processing also comes into play
- 4 objs with 2 black no.s
- flash for 1/5 sec
- followed by random dot masking field (to eliminate any residual perception that might remain after the stimuli were turned off)
- told to report the black nos.
- then saw at the four locations where the shapes have been
- here, they have to divide their attention into IDENTIFY NO. AND SHAPE
- this reduces their ability to focus on the shapes
- RESULTS:
- they ended up seeing shapes that were made of a combi of the features from 2 diff stimuli
- these combis of features of diff stim are called illusory conjunctions
- IC happens cause in preatten stage, each feature exist independently of the others
- IC also occurs when not enough atten is given to objs
- redness or curvature at this stage is not assoc with a specific obj
- they are free floating here
NOTE THAT:
1. FIT involves rapid initial parallel process (preattentive)
2. A serial process (attention demanding)
- features can be combined by focusing attention to the location of the obj
- feature combination can be influenced by stored knowledge
33
What is Single feature search and Conjunctive search?
Single feature search:
- focus on identifying a target amongst distractors that differ from target by a unique visual features
- eg. color, shape, orientation, size
Conjunctive Search:
- Focus on identifying a target amongst distractors processing one or more common visual features with the target itself
- eg. same visual character, same color
- eg. searching for (red) K among (red) C and K
