The changing face of face research

1. The changing face of face research Vicki Bruce School of Psychology Newcastle University

3. and many, many more......

4. Bruce & Young (1986) EXPRESSION ANALYSIS STRUCTURAL ENCODING FACIAL SPEECH ANALYSIS FACE RECOGNITION UNITS DIRECTED VISUAL PROCESSING PERSON IDENTITY NODES COGNITIVE SYSTEM NAME GENERATION

5. (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

6. Simple ‘box and arrow’ outline replaced in 1990s by computer model – Interactive Activation with Competition

7. 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

10. 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

13. Name retrieval in IAC? • Burton and Bruce (1992) proposed names like other semantic information but with fewer connections.

15. 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.

16. After Bredart et al (1995) QJEP

17. Much better ideas about the kinds of visual representations that form the core of the ‘FRUS’ or equivalent

18. 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.

22. 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

23. Results Face recognition Correct PIN identified

24. Distinctiveness Human subjects rated neutral versions of faces. (1=typical, 15=distinctive) Correlation between human rating and cycles-to-reach-PIN = - 0.31

25. Semantic priming Pairs defined as sharing 2 semantic units Mean cycles to threshold for test faces

26. 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

27. Burton, Bruce & Hancock, 1999

28. 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.

33. Face Recognition Units?

34. 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)

35. Development of cognitive neuroscience models (Haxby)

36. After Bruce & Young (1986) After Haxby et al, 2000 Diagram from Calder & Young (2005)

37. 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...)

38. Exciting hot topics...Gaze • Information from dynamic patterns • Interactions between systems • Gaze and social cognition: certainly eyes are special.. • But why eyes?

39. -dynamics -interactions -gaze! Bruce & Young (1986) EXPRESSION ANALYSIS STRUCTURAL ENCODING FACIAL SPEECH ANALYSIS FACE RECOGNITION UNITS DIRECTED VISUAL PROCESSING PERSON IDENTITY NODES COGNITIVE SYSTEM NAME GENERATION

40. Eyes important for..Social reasons • We look at other people’s eyes for • Intimacy • Control • Regulating conversational turns etc

41. 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

42. From D. Riby & Hancock (2008) Neuropsychologia

43. 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.

44. And if you don’t want to be recognised?

45. 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.