ATTENTION Lecture 3 Learning Objectives 1 Describe the

ATTENTION Lecture 3

Learning Objectives 1. Describe the 3 dimensions used to define attention 2. Explain the factors that can drive attention 3. Describe Broadbent’s and Triesman’s filter theories of attention 4. Describe the dichotic listening paradigm and what has been discovered about attention using the technique 5. Explain what is meant by ‘spotlight of attention’

Learning Objectives 7. Explain capacity theories of attention 8. List the characteristics of automatic and controlled tasks; explain Shiffrin & Schneider’s classic experiment and how it demonstrates those characteristics 9. Define 2 versions of the binding problem and how attention might be related to both 10. Describe a classic laboratory visual search task and the typical results 11. Describe Triesman’s Feature Integration Theory 12. Explain the link between attention and consciousness, including inattentional blindness and change blindness

Theories of Attention Everyone knows what attention is, but nobody can define it! There are several theories of the mechanisms of attention; each one explains how attention is used under different circumstances Attention as a filter…………… Attention as a spotlight ………………. . . Attention as a mental resource………… Attention as a feature binder…………… Selective attention Vigilance Divided attention Visual search

Attention is the process of concentrating mental effort on sensory or mental events Attention has a limited capacity There are many different types of attention but they all vary along certain dimensions Exogenous-endogenous Overt-covert Automatic-controlled

Attention is driven by stimulus saliency Motion Colour Brightness Contrast Orientation Attention can be driven by other “important” information and previous knowledge

Attention is closely linked to consciousness but they are not synonymous Change blindness https: //www. youtube. com/watch? v=b. D__D 80 X 3 uc Inattentional blindness https: //www. youtube. com/watch? v=f 94 o 3 B 3 cs. YI

Filter Theories of Attention Selective Attention Filter theories believe attention acts like a bottleneck that only lets some information through at a time The attentional filter selects attended information for processing and filters out everything else

Filter Theories of Attention Dichotic listening task Broadbent first proposed a theory of auditory attention based on results of dichotic listening tasks

Filter Theories of Attention Dichotic listening task People are good at paying attention to message in one ear only – i. e. people are good at selectively attending! People noticed sensory information in unattended ear People did notice the meaning of the message in the unattended ear, unless the message was very brief

Filter Theories of Attention Broadbent’s Early Selection Filter Model

Filter Theories of Attention Broadbent’s Early Selection Filter Model Problems: 1. People are aware of their own name in an unattended message 2. Participants ‘follow’ a meaningful message in the unattended ear

Filter Theories of Attention Triesman’s Attenuation Model Attended signal is stronger than other stimuli after passing through the filter, but… Unattended stimuli may be more intense Unattended stimuli may be ‘more important’ Unattended stimuli may be ‘more likely’

Capacity Theories of Attention Divided Attention We have a fixed amount of attentional resources that we can use to perform mental work More cognitive load = more attentional resources used We have some control over how we allot these resources Primary task Secondary task Available attention capacity

Capacity Theories of Attention Divided Attention We have a fixed amount of attentional resources that we can use to perform mental work More cognitive load = more attentional resources used We have some control over how we allot these resources Primary task Available attention capacity Secondary task

Capacity Theories of Attention Divided Attention The Flanker compatibility task demonstrates this attention ‘spill over’ with low load tasks

Capacity Theories of Attention Divided Attention With practice controlled processes can become automatic Automatic Processes Controlled Processes Do not require attention Require attention Fast Slow Parallel Serial Cannot be modified once started Under conscious control

Capacity Theories of Attention Shiffrin & Schneider (1977) Independent variables: Memory set (target): letters or numbers Frame size: 1, 2 or 4 Target presence: present or absent Distractor items: same category or different category

Capacity Theories of Attention Shiffrin & Schneider (1977) Same category Never became automatic Same category condition required 400 ms to achieve 95% accuracy Response time increased as the number of distracter items increased Different category After ~600 trials task became automatic Required only 80 ms per frame to achieve 95% accuracy Number of items per frame didn’t affect response time

Capacity Theories of Attention Stroop Task yellow red green blue green yellow red blue

Capacity Theories of Attention Driving and Cell Phones We are less able to detect sudden changes and react quickly when using cell phones while driving… …but I have lots of practice driving so it’s automatic… …so I’ll use hands-free… …but I can listen to the radio… …but I can talk to passengers in the car…

Capacity Theories of Attention Cowan suggests we can attend 4± 1 items at a time How many dots are there? Multi-object tracking https: //www. youtube. com/watch? time_continue=9&v=MGBNj 5 i 62 Wo 22

Attention as a Spotlight Vigilance How do we direct attention? Posner, 1980

Attention as a Spotlight Vigilance

Attention as a Spotlight Vigilance Neisser & Becklen, 1975 We can selectively attend objects in the same spatial location

The problem with visual features Stemming in part from research in visual perception and questions from philosophy, attention researchers are faced with the binding problem 1. 2. How are separate features combined into a single “object”? How do brain processes construct phenomenological experience? Patient data indicates that object feature identification can occur without binding Item features outside of conscious awareness are not bound

Attention as a feature binder The binding problem (1) One role of attention may be to bind features Visual search tasks involves using attention to focus on object features in a particular location Consider 2 features: shape and colour

Attention as a feature binder The binding problem (1) Feature search Green circle among blue squares – search for green item OR circular item Conjunction search Green circle among green squares and blue circles – search for green circle

Attention as a feature binder The binding problem (1) Typically a visual search task in a lab has 3 independent variables: Independent variables type of search number of distractors presence of target Dependent variable reaction time to respond

Attention as a feature binder The binding problem (1)

Attention as a feature binder The binding problem (1) According to feature integration theory visual search is a 2 -stage process 1. Single feature does not require attention and “pops out” automatically – this is the preattentive stage

Attention as a feature binder The binding problem (1) According to feature integration theory visual search is a 2 -stage process 2. Binding features requires attention – this is the focused attention stage

Attention as a feature binder The binding problem (2) Evidence suggests that while we can process multiple pieces of information in parallel, there is a limit on what we can consciously process at one time Attention may help select information for conscious processing Attention is closely linked to consciousness but they are not synonymous