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
Neutral Expressing
faces (/50) faces (/136)
Shape-free (50-bit)
50
129 (95%)
Raw image (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
Face prime
Unrelated prime
65
Related prime
38
Name prime
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
Unprimed
78.6
Primed with same
image
60.1
Primed with
different image
64.8
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.