Lecture 11

May 2005

(Updated Dec 2006)

Neuroimaging and attitudes to faces

Neuroimaging + attitudes to faces1. Attraction

(ventral thalamus, medial orbito-frontal cortex)

- attractiveness and social interest interact to determine the ‘reward value’ of faces

1. Avoidance(insula)- disgust expressions- unattractive faces- untrustworthy faces

3. Dynamic emotion- moving faces

Attractive Faces

Attractive Faces O’Doherty et al. 2003

Medial orbital-frontal cortex is a reward centre Activity increased by attractive faces

-3-3

Medial orbito-frontal cortex

Smiling and Neutral Faces

Happy Neutral

Attractiveness and Smiling

Happy Mid-range Neutral0.00

0.05

0.10E

ffec

t si

ze

Effect of attractiveness on medial orbito-frontal cortex greatest when faces are engaging the viewer

1. Attractiveness + social interest

Attractive faces activate ‘reward’ structures more than unattractive faces

Responses to attractive faces biggest when the person is engaging with us (i.e. smiling)

In O’Doherty et al. engagement was signalled by expression

Engagement can also be signalled by direct gaze

GAZE

Averted

Direct

Kampe et al. 2001

Kampe et al. 2001

ventral thalamus activity modulated by attractiveness & gaze direction

1. Attractiveness + social interest

Attractive faces activate ‘reward’ structures more than unattractive faces (ventral thalamus, medial orbito-frontal cortex)

Responses to attractive faces biggest when the person is engaging with us (i.e. smiling, direct gaze)

O’Doherty et al. 2003 Kampe et al. 2001

2. Avoidance

- disgust expressions- unattractive faces- untrustworthy faces

75% disgust 150% disgust

Disgust Expressions & Insula Cortex (Phillips et al. 1997)

Increased insula activity when viewing disgusted faces

2. Avoidance

Insula cortex also activated by disgusting odours

Keyser et al. (2004)

Lateral PFC

+22

Insula

R

Unattractive Faces

Activity increases with unattractive facesO’Doherty et al.

Lateral PFC

+22

Insula

R

Untrustworthy Faces

Increased insula response to faces judged untrustworthy (Winston et al., 2002 Nature Neurosci)

2. Avoidance

Faces we might want to to avoid:

unattractive (possibly unhealthy?)

disgusted (there is a source of contagion about?)

untrustworthy (they’ll cheat us?)

activate the insula cortex

[also disgusting odours]

Attraction and avoidance (Key themes)

Attraction

Ventral thalamus

Medial orbito-frontal cortex

!Approach this person!

Avoidance

Insula cortex

‘disgust region’

!Avoid this person!

Activated by attractive faces (especially if engaging with you)

Activated by unattractive, untrustworthy and

disgusted faces

Dynamic expressions

All the studies we’ve discussed in this course

used static images

Sato et al. asked if facial movements might

communicate important information

Dynamic facial expressions caused more brain activity than static

expressions

Dynamic (non-face) mosaics caused no more brain activity than static

mosaics

Movement matters!

Future directions

Individual differences in neural responses to faces

Use of dynamic faces

Use of computer graphic methods to manipulate

dynamic facial cues

Integration of social and physical cues in perception

Next week

4 key revision topics covered

1. Does attractiveness signal health?

2. Self-resemblance as a cue of kinship

3. Effects of hormonal profile on face preferences

4. Condition-dependent mate preferences