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The changing face of face
research
Vicki Bruce
School of Psychology
Newcastle University
and many, many more......
Bruce & Young (1986)
EXPRESSION
ANALYSIS
FACIAL
SPEECH
ANALYSIS
DIRECTED
VISUAL
PROCESSING
COGNITIVE
SYSTEM
STRUCTURAL
ENCODING
FACE
RECOGNITION
UNITS
PERSON IDENTITY
NODES
NAME
GENERATION
(Selective) developments since
1986
•
•
•
•
Simple �box and arrow’ outline replaced in
1990s by computer model – Interactive
Activation with Competition
Much better ideas about the kinds of visual
representations that form the core of the
�FRUS’ or equivalent
Development of cognitive neuroscience models
(Haxby and many others)
Emergence of �social cognition’ and central role
played by gaze
Simple �box and arrow’
outline replaced in 1990s
by computer model –
Interactive Activation
with Competition
Burton, Bruce and Johnston
(1990)
• IAC - Interactive activation with
competition (cf early McClelland &
Rumelhart)
• Pools of units for features, FRUs, PINS,
SIUs
• Excitation between pools, inhibition within
pools
• Familiarity decisions when PIN reaches
threshold
Provides good simulations of
• Repetition priming - via strengthened
connections (so long-lasting, but not cross
domain)
• Associative priming - via temporary
activation (so short-lasting but crosses
domains)
• Covert recognition in prosopagnosia
• Predicted face-name matching in patient
ME
Name retrieval in IAC?
• Burton and Bruce (1992) proposed names
like other semantic information but with
fewer connections.
Name retrieval in IAC?
• This position, however, has not stood up
to empirical test.
• E.g. Bredart et al (1995) showed that you
were not slower (actually faster) to name
people about whom you knew a lot rather
than a little information.
After Bredart et al
(1995) QJEP
Much better ideas about the
kinds of visual
representations that form
the core of the �FRUS’ or
equivalent
Burton, Bruce & Hancock
(1999)
Cognitive Science
• IAC model of person
recognition (familiar)
• FRUs driven by
distributed reps PCA
• Look at how model
behaves in
recognition and
priming now using
real faces as input.
Data set
• 50 young men
• all captured in a neutral expression and
2 or 3 other expressions
In total
• 50 neutral faces + 136 expressive faces
Results
Face recognition
Correct PIN identified
E xpressing
N eutral
faces (/50) faces (/136)
Shape-free (50-bit)
50
129 (95% )
R aw im age (50 bit)
50
113 (83% )
Shape-free plus shape (70 bit)
50
131 (96% )
Distinctiveness
Human subjects rated neutral versions of faces.
(1=typical, 15=distinctive)
Correlation between human rating and cycles-toreach-PIN
= - 0.31
Semantic priming
Pairs defined as sharing 2 semantic units
Mean cycles to threshold for test faces
U n related p rim e
R elated p rim e
Face p rim e
65
38
N am e p rim e
63
41
Repetition priming
Procedure:
1. Present prime face
2. Cycle model & Hebb update
3. ISI - present lots more faces (c. 100)
4. Present test face (same or different view)
Mean cycles to threshold for test faces
U n p rim ed
7 8 .6
P rim ed w ith sam e
im age
6 0 .1
P rim ed w ith
d ifferen t im a ge
6 4 .8
Burton, Bruce & Hancock,
1999
How do we represent familiar
faces?
• Just the average of each distinct image we see
of them?
• See Burton, A.M., Jenkins, R., Hancock, P.J.B.
& White, D. (2005) Robust representations for
face recognition: The power of averages.
Cognitive Psychology, 51 (3), 256-284
• Jenkins, R. & Burton, A.M. (2008), Science, 319,
p.435.
Face Recognition Units?
What about Face Space?
• Valentine (1991) and later
• Adaptation studies (Rhodes et al..)
• PCA dimensions can be thought of as
forming the dimensions of �face space’
(though this is not the only possible model)
Development of cognitive
neuroscience models
(Haxby)
After Bruce & Young (1986)
After Haxby et al, 2000
Diagram from Calder & Young (2005)
Are faces special?
Or, is face recognition special?
• Innateness (congenital prosopagnosia,
congenital cataracts suggest sensitive
period)
• Localisation (FFA active even in
congenital Ps)
• Specificity (still debated...)
Exciting hot topics...Gaze
• Information from dynamic patterns
• Interactions between systems
• Gaze and social cognition: certainly eyes
are special..
• But why eyes?
Bruce & Young (1986)
EXPRESSION
ANALYSIS
-dynamics
-interactions
-gaze!
FACIAL
SPEECH
ANALYSIS
DIRECTED
VISUAL
PROCESSING
COGNITIVE
SYSTEM
STRUCTURAL
ENCODING
FACE
RECOGNITION
UNITS
PERSON IDENTITY
NODES
NAME
GENERATION
Eyes important for..
Social reasons
•
•
•
•
We look at other people’s eyes for
Intimacy
Control
Regulating conversational turns etc
Cognitive reasons
• We look at other people’s eyes to
– Mind-read (Baron-Cohen)
– Establish shared attention
– Dogs do this too..(Miklosi et al, 2003)
• Can’t ignore what another person gazes at
– Gaze cuing
– But sometimes we must look away (gaze
aversion)
• Different gaze patterns in different genetic
learning disorders
From D. Riby &
Hancock (2008)
Neuropsychologia
So, why eyes?
• We need to look at them/use them for
other social and cognitive purposes
• They tell us about gaze and also other
expressions
• They don’t change when other facial
features do.
• Probably explains why representations of
familiar faces are weighted to the eyes.
And if you don’t want to be
recognised?
School of Psychology
Summing up
• Bruce and Young (1986) mapped broad
relationships between different processes
of face perception.
• In past 25 years we have begun to
understand the mechanisms.
• Social cognition is the new hot topic, and
there’s plenty left to learn.
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