what is attention?
Mental process of concentrating effort on a stimulus
four ideas of attention
- We are constantly confronted with more info than we can attend to
- There are serious limitations in how much we can attend to at one time
- We can respond to some info + perform some tasks with little if any attention
- With sufficient practise + knowledge, some tasks become less demanding of attention
focused (selective) attention
Select one input while ignoring all others
Eye movements
Move eyes so that input of interest falls on central fovea
Motion triggers reflex of movement
Head movement
Position ears for better hearing
visual search
Indicate as quickly as you can whether a particular target is present
Takes longer + requires more attention when searching for a combo of features
feature integration theory
Two processing stages:
1. Basic features processed rapidly + pre-attentively in parallel across visual search
2. Slower serial process with focused attention
attention networks: exogenous
bottom up
stimulus driven
automatically shift attention
peripheral cues
occurs spontaneously in the environment
illusory conjunctions
No difficulty perceiving features on display
However, unsure how features are combined
Report illusory conjunctions
attention networks: endogenous
top down
goal directed
controlled by expectations
central cues
driven by motivation
Posner (1980)
Select the side a flash of light is presented
left/right of a central fixation cross
Flash preceded by a central cue
Arrow correctly points to a flash location (valid)
Arrow incorrectly points to flash location (invalid)
Flash preceded by peripheral cue
Outline of shape in flash location (valid)
Outline of shape opposite side of flash location (invalid)
majority of cues valid
Central cues: RT’s faster for valid cues
Peripheral cues: RT’s faster for valid cues
Separate exogenous + endogenous systems
- Expect that cues are reliable
- Endogenous attention used when central cues present + controlled by expectations
– Exogenous attention used when peripheral cue present + stimulus driven
majority of cues invalid
Central cues: RT’s same for both valid / invalid
Peripheral cues: RT’s still faster for both valid trials
Separate exogenous + endogenous systems
- Expect that cues should be ignored
- Endogenous attention used when central cues present + controlled by expectations
- Exogenous attention used when peripheral cue present + stimulus driven
focused auditory attention
Lessons learned from vision applied to our sense of hearing
Select sounds of interest, while ignoring others
Must separate different auditory stimuli
cocktail party problem: Cherry (1953)
How do we focus on one convo at a time?
Using physical differences
Extract little info from unattended stimulus
Exogenous, as hear salient info in unattended stimulus
cross modal attention
Coordinate info from two or more modalities simultaneously
ventriloquism effect
Close together in time / space
Match expectations
Example of visual dominance
McGurk effect
Sound same in both clips
Further evidence for visual dominance
Input from vision influences auditory perception
divided attention
Present two stimulus inputs at the same time
Must attend + respond to ALL inputs
Also known as multi-tasking
Tells us the capacity of attention
automatic processing
Practise makes perfect
Assume that processes become automatic
Two major theoretical approaches
1. Traditional approach
2. Definitions of automaticity
traditional approach
Controlled processes (serial)
Limited capacity
Require attention
Used flexibly in changing circumstances
automatic processes
No capacity limitations (parallel)
Do not require attention
Hard to modify once learned
definitions of automaticity
Reject assumption that clear cut distinction between controlled + automatic processes
Four factors associated
1. Unconscious
2. Efficient
3. Fast
4. Goal-unrelated
Not always found together
importance of attention
Helps us to:
Focus on a specific object to gain more info
Bind features together so we can perceive a coherent object
Ignore unwanted distraction
what causes change blindness?
No single answer
- Representations may be incomplete due to limited attentional focus
- Representations may decay or be overwritten
- Representations of pre-change stimulus may be limited to the unconscious
- Impossible to compare pre and post change
- Perceptual accuracy sacrificed; so we have continuous + stable perception of environment
inattentional bias
failure to notice an unexpected, but fully visible item when attention is diverted to other aspects on display
