Lecture 4 - Attention Flashcards
What is attention?
Ability to focus on specific stimuli or locations in our environment (including our own body)
- selective: attending to one thing while ignoring others
- divided: paying attention to more than one thing at a time
History of studying divided attention
Attention started being intensely studied in the 1950s as a response to technological developments and human machine interactions, e.g. challenges of optimising procedures for pillions and dirvers of tanks
Selective e attention
The ability to focus one one message and ignore others
- we do not attend to a larger fraction of the information in the environment
- we filter out a lot of information and promote other information for further processing
Research method - dichotic listening
Cherry 1953
One message is presented to the left ear and another to the right ear via headphones (shadowing/dichotic listening)
Ppts “shadows”/ignores one message to ensure they are attending to the other message (selective listening and repeating attended mesaage)
Can er completely filter out the message to the unattended ear and attend only to the shadowed message?
Ppts can’t report the content of the message in the unattended ear but
- knew there wads a message
- knew the gender of the speaker
Hence, the unattended message is processed at some level
- cocktail party effect - we almost always hear our own name, no matter if we are paying attention to something else
- change in voice is noticed
- change in tone is noticed
Models of selective attention
Where does the attention filter occur?
Early or later processing hierarchy?
- early selection model, e.g. Broadbent’s filter model
- intermediate selection model, e.g. Treinsnam’s attenuation model
- late selection model, e.g. MacKay (1973)
Broadbent’s filter model
Sometimes also called a ‘bottleneckj’ model
Filters message before incoming information is analysed for meaning
Messages ——> sensory memory ——> filter -(attended message)-> detector -> to memory
- Sensory memory - holds all incoming information for a fraction of a second. Transfers all information to next stage
- Filter - identified attended message based on physical characteristics. Only attended message is passed on to the next stage - can process different frequencies so we can effectively listen to it (e.g. frequency of male vs female voice)
- Detector - processes all information to determine higher-level characteristics of the message
- Short-term memory - receives output of the detector. Holds information for 10-15 seconds and may transfer it to long-term knowledge
Limitations of Broadbent’s model
Certain things it cannot explain
Why woollen the ppt’s name get through?
- cocktail party phenomenon - ability to focus on one stimuli while filtering out other stimuli, especially at a party where there are a lot of simultaneous conversations
Why ppts can shadow meaningless messages that switch from one ear to another
- dear aunt Jane experiment (Gray and Wedderburn, 1960)
- left ear = dear 7 Jane
- right ear = 9 aunt 6
- what they heard = dear aunt Jane
Tresiman’s attenuation model
Intermediate selection model:
- attended message can be separated from unattended messages early in the information-processing model
- select5ion can also occur later
- this is very similar to Broadbent’s, only difference is that it believes there is still attention of unattended messages (just much less than attended messages), which can explain the cocktail party effect
Messages ——> attenuator -(attended and unattended messages)-> dictionary unit-> to memory
Introduction of the attenuator to replace Broadbent’s filter
- analyses incoming messages in terms of physical characterstics
- attended message is let through the attenuator at full strength
- unattended message is let through at a much weaker strength
Dictionary unit
Contains words, each of which has a threshold for being activated
Words that are common or imprtant have low thresholds
Uncommon words have high threshold
Threshold is determined by saliency
Late selection models n
Selection ones not occur until after meaning has been analysed
MacKay (1973)
- in attended ear, ppts heard ambiguous sentences (e.g. “they were throwing stones at the brink). In unattended ear, ppts heard either ‘river’ or ‘money’
- ppts chose which was the closest meaning of the attended message
- they were throwing stones toward the side of the river yesterday
- they three stones at the savings and loans association yesterday
- meaning of the biasing word affected ppt’s choose while ppts were unaware of the presentation of the biasing word
Load theory of attention
We have a certain capacity for attention
Low-load primary task will take up less resources leaving a lot of remaining perceptual capacity whereas high-load primary task will take up a lot or all of the resources leaving little or no remaining perceptual capacity
Processing capacity
How much information a person can handle at any given moment
Perceptual load
The difficulty of any given task
A) low-load (easy) tasks - take up less processing capacity. Task may leave resources available for processing unattended task irrelevant stimuli
B) high-load (difficult) tasks - take up more processing capacity, meaning use all cognitive resources and don’t leave any reproduces to process unattended task irrelevant stimuli
- you can listen to loud music or audiobooks while driving your car on the motorway (low capacity task)
- you have to pause or turn down the volume while parking your car in a difficult spot (high capacity task)
The strop test
Stroop effect
- name of the word interfered with the ability of name ink colour - e.g. trying to identity the name of the colour blue while the word that is written in blue ink is yellow
- cannot avoid paying attention to the meaning of both words
- this is because reading is high trainers and automised
Training effects
The more you do a type of task, the
A) better you get at it)
B) more automised the task becomes
The more automised a task is, the less processing capacity it takes up (reduced cognitive load because less executive function is used)
Examples:
- frequent video game players are less affected by high visual load
- the more often you speak a foreign language, the more automatic is becomes
How to measure overt attention?
Overt attention is observable attention and can be observed in eye movements
- saccades - rapid movement of the eye from one place to another - we are actually blind during saccades and our brain is falling in the image
- fixations - short pauses on points of interest - fixates = central vision
- studies by using an eye tracker
Salience of stimuli (bottom up)
Some objects are more salient that others e.g. people, houses, moving objects
Contrast is also salient
Top-down determinants of eye movements
Scene schemas
Study done where ppts were shown an image of a kitchen
First asked to look at the images and imagine they were making breakfast - eye movements focused in areas you may need, e.g. cupboard, counter, oven, table - attenton mao showed a lot of attention in specific places
- then told to look at image and image they were looking for their keys - movements and attention much more spread across the room
Determinants of eye movement
Stimulus salience:
Areas and objects that stand out and captive attention
- bottom-up process
- depends on characteristics of the stimulus
- colour and motion are highly salient
Scene schemas:
- knowledge about hat is contained in typical scenes
- top-down process
- help guide fixations from one area of a scene to another
Eye movements are determined by task
- eye movements precede motor action b y a fraction of a second
Covert attention: attention without eye movements
Coding procedure:
Procedure for testing memory in which a ppt is presented with cues, such as words and phrases, to aid recall of previously experienced stimuli
- donder’s subtraction method for response times
- attention to a location: ppts respond faster to a target at an expected location than at an unexpected location
- even when eyes kept fixed
Magic tricks - cueing can be used as a form of deception in magic tricks
Divided attention
Practise enables people to simultaneously do two things that were difficult at first
- hug holy practised (automised) tasks allow us to divide our attention to other things
- depends on the difficulty of the task
- true multitasking is almost impossible unless all tasks are easy to highly practised
Divided attention between remembering target and monitoring readily presented stimuli (Schneider and Shiffrin, 1977)
There is one target stimulus in the memory set (the 3) and four target stimuli in each frame
Memory set
- one to four characters called stimuli
Test frames
- could contain random dot pattern, a target, distractors
Improvements in performance with practise in this experiment
Around indicates the point at which ppts reported that the risk task has become automatic
Automatic processing occurs without intention and only used some of a person’s cognitive resources
Distractions - cell phone use
Driving (bike or car) can be a highly automised task (at least under easy conditions i.e. no traffic, known route)
- phone sue (hands or no hands) drastically reduces our ability to focus and drive safely
- ppts on phone missed twice as many red lights and took longer to apply the brakes - Strayer and Johnston (2001)
~ some result suing hand-free cell phone
hat happens if we don’t attend?
Stimuli that are not attended are not perceived, even though a person might be looking directly at it (inattentional blindness)
Difficulty in detecting changes in similar, but slightly different scenes that are presented one after another
These changes are often easy to see once attention is directed to them, but are usually undetected in the absence of appropriate attention (change blindness)
The blinding problem
Binding is the process by which features such as colour, form, motion and location are3 combines to create our perception of a coherent object
- binding problem” the problem of explaining how an object’s individual features become bound together, explained by Treisman’s feature interpretation theory
Feature integration theory
Every object has multiple features that need to be integrated after feature detected have or vessels them individually
Objects have a shape, colour, filling, size, position, orientation, etc
Object -> pre attentive stage (analyses into features) -> focused attention stage (combine features) -> perception
Mostly bottom-up processing
Top-down processing influences processing when ppts are told what they would see
- top-down processing combines with feature analysis to help one perceive things accurately
Preattentive stage
- object analysed into features
- automatic -> no effort or attention, unaware of process
Focused attention stage
- attention plays a key role
- features are combined into perceptual object
Illusory conjunction is a situation in high features from different objects are inappropriately combined
Ppts report combination of features from different stimuli
Illusory conjunctions occur because features are “free floating” combined the second stage of FIT called the focus attention stage
Balint’s syndrome
Bilateral parietal lesions
Patients fail to apprehend all but one of simultaneously presented objects at the same location
Condition is object-based, not location based
- multi coloured dots are seen properly is they are connected by the lines
Inability t focus attention on individual objects
High Humber of illusory conjunctions reported
Neural correlates of attention
Attention network - switch on, switch off
Default mode network - day dreaming
Never on at the same time, never both off at the same time
