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The effects of facial emotions upon orienting visual attention
Dr. David Crundall
Rm 315
Office hours: 10 am – 12 noon, Wed.
Catherine Thompson
Rm 320 email: [email protected]
In class: Outside class:
• Week 1: Introductory lecture; devise initial design
• Week 2: Finalise design; set up and pilot experiment
• Week 3: Problem solving class
• Week 4: Analyse data• Week 5: Present
results to the group
• Week 1: Reading and discussion in experiment groups
• Week 2: Piloting can be done outside class
• Week 3: Run all participants
• Week 4: Finish analysis and write talk
• Week 5: Write up the project
Today’s sessionQ1. Do emotional faces capture our attention?
Q2. Do emotional faces direct our attention?
After the background lecture you will split into groups of three. Have a look at the experimental templates in E-prime and decide in your group which question you want to answer and which variables you wish to manipulate.
A quick (re)introduction to attention
• The spotlight metaphor of attention (e.g. Eriksen & Eriksen, 1974)
• Modifications include the zoom lens metaphor (e.g. Eriksen and Yeh, 1985) and the gradient model (La Berge, 1989)
• Attention moves like the eyes (often preceding eye movements) focusing first on one thing and then the next
• How do we shift attention?
These theories evolved from the single channel theories of
Broadbent and others.
Four types of attention shift
Automatic
(Superior Colliculus)
Controlled
(Prefrontal, FEFs)
Overt
Covert
Reflexive saccade
(e.g express saccade, target
ellicited saccade)
Voluntary saccade
(e.g anti-saccade)
Exogenous attention
Endogenous attention
Sereno, 1992
Peripheral cuing:
XF
Peripheral cuing…
• orients attention quickly (Cheal & Lyon, 1991),• benefits for the cued location occur without costs
to the uncued location (Posner & Snyder, 1975), • the cue does not need to be predictive (Jonides,
1981), • benefits rapidly disappear over time (Muller &
Rabbitt, 1989).• Also called exogenous orienting
Central cuing:
XF <
Central cuing…
• orients attention more slowly • can produce costs for uncued locations• can be overcome by conscious (top-down)
control• also called endogenous orienting
There has been much argument about whether these two types of cue effect represent two distinct underlying systems.
Q1. Do emotional faces capture attention like a peripheral cue?Negative faces are easier than happy faces to pick out of a
matrix of neutral faces (Hanson & Hanson, 1988; Fox et al., 2000)
Hermans, Vansteenwegen and Eelen (1999) found Ss looked more at spiders than flowers in a display at short durations. From 2000-3000 ms however the high spider-anxious Ss looked less at spiders and more at flowers. Vigilance-avoidance? Rohner (2002) found the same with pairs of faces
RTs to a probe task were faster when the probe occupied the location of an angry or fearful face (Bradley, Mogg, & Miller, 1998; Fox, 2001)
+F
Q2. Do emotional faces direct attention like a central cue?
Friesen and Kingstone,1998:
They believed that gaze direction was of special significance in orienting an observer’s focus of attention.
Using schematic faces they found that participants were faster to respond to targets that were validly cued by gaze direction.
Though gaze direction was a central cue, the results were more akin to those found using a peripheral cue.
F
Matthews et al. 2003:• They used photos of faces showing fear (compared to neutral-emotion, control faces). • Gaze direction could be a valid, invalid or neutral predictors of target location:
• They used two Stimulus Onset Asynchronies: 300 ms and 700 ms
F
T
F
Valid
Invalid
Neutral
F
F
Matthews et al. 2003:
They found that fear faces produced faster responses to validly cued targets than faces with no emotion – but only in high anxiety (HA) individuals.
HAs were also slower when the fear faces had a central gaze (a neutral cue) suggesting that they had difficulty disengaging from a fear face.
A small pilot study however failed to replicate these results with anger (perhaps something to do with amygdala function? – Adams et al, 2003) .
Problems with Matthews et al. study:
1. They used valid, invalid, and neutral gaze cues. However the neutral gaze cues removed temporal cues as well as location cue.
2. If fear faces make us orient attention in order to identify the location of a threat, surely starting with a direct-gaze fearful face, places the source of the fear with the observer?
Use criticisms of others’ research as starting points for
your own design
F
F
Neutral, Fear, Anger, Disgust – Happy faces could also be arranged!
Things to consider for your experiment
Obvious Factors to manipulate:
2 levels 3 levels
Cue Validity Valid vs invalid vs neutral?
Emotion Neutral vs fear vs anger?
SOAs e.g. 300 vs 700 vs 1100?
Cue predictability?
50:50 vs 70:30 vs 30:70?
Participant anxiety
High vs low
There are many more less obvious factors that might be
more exciting
Cuing effects will be increased if more time is given to process the face before the cue appearsVary cue validity and time from face onset to cue onset Fear faces will produce greater cuing benefits at short SOAsVary cue validity, facial emotion, and SOAHighly anxious individuals will show a greater sensitivity to cue predictability than low anxious individualsVary cue validity, cue predictability, and participant anxiety. Only use fear faces, or use fear and neutral faces, creating a fourth variable
Which type of Analysis of Variance is most appropriate
for each design?
Sample hypotheses:
Where to run and save your experiment:
The Psychology Server
Your personal file space
Practicals on 'XServe (upsyc)'
class_share on 'XServe (upsyc)'
Write protected
Where to run and save your experiment:
• Copy a template from the Practicals folder into either your personal server area or a class_share folder (pros and cons to each)
• Modify the template to produce your experiment.• To run the experiment, copy down the e-prime
file to the C drive of the computer you are working on. Place it in ‘DECs Second Yr Lab’
• When your participant has finished copy the data files back to either your personal server area or your class_share folder.
Mistakes to avoid
• Don’t get your SOAs and your ISIs mixed up• A neutral cue is not the same as a neutral
emotion• Don’t forget to make sure that your subjects are
sitting at an exact distance from the screen• Do not run your experiment from the server. All
your timings will be incorrect• Do not leave data on the C drive of any computer
(preferably save it to your personal server space)
What next?
• Get into groups of three or four• Have a look at the e-prime template experiment
available in practicals\DECs Second Yr Lab on the server
• Discuss your design in your group• Have your basic design agreed with the lecturer
or the demonstrator before you leave.