Program & Abstract Book - EPFL Latsis Symposium 2009

EPFL Latsis Symposium 2009: Understanding Violence
56
P-2
February 11-13 2009
in D i v i D u a l D i f f e r e n c e s in a g g r e s s i o n
m o D u l a t e e a r l y f r o n t a l r e s p o n s e t o
a g g r e s s i v e f a c i a l D i s p l a y s .
Bediou Benoit, 1 3 ; Eimer, Martin 2 ; Calder, Andrew J. 1
1 Medical Research Council - Cognition and Brain Sciences Unit,
15 Chaucer road, CB2 7EF Cambridge, UK.; 2 School of Psychology,
Birkbeck College, University of London, Malet Street, London
WC1E 7HX, UK; 3 Swiss Center for Affective Sciences CISA – University
of Geneva, Rue des Battoirs, 7, CH 1205 Geneva, SWIT-
ZERLAND
Converging evidence from human and animal research suggest that aggressive
behaviour arises from a dysfunction in the neural circuitry of
emotion-regulation, especially in the connection between the prefrontal
cortex and the amygdala. Both clinically aggressive individuals and healthy
volunteers with elevated risk for aggression show increased amygdala and
decreased prefrontal responses to facial signals of aggression. Individual
differences in reward-drive have been associated with increased attention
toward facial signals of aggression, heightened experience of anger and
vulnerability to display aggressive behaviour.
Here, we investigated the temporal dynamics of the interaction between
an aggression-related personality trait (‘reward-drive’—the drive to gain
reward, Carver &White, 1994) and the neural response to angry faces.
We recorded high-density (64-electrodes) Event Related brain Potentials
(ERPs) in subjects scoring high (N=12) and low (N=12) on the rewarddrive
scale while they viewed angry, sad and neutral faces.
Replicating previous findings, ERP results showed an enhanced frontal and
frontocentral positivity in response to angry and sad faces compared with
neutral faces from 130 to 200ms post stimulus. Crucially, reward-drive selectively
modulated the midline frontocentral response to aggressive facial
displays within 200-300ms after stimulus onset—compared to low rewarddrive
subjects, individuals scoring high on the reward-drive scale showed
a reduced midline frontocentral positivity for angry faces relative to neutral
and sad expressions.
Results are consistent with recent fMRI studies showing reduced ventromedial
prefrontal response to angry faces relative to neutral and sad expressions
in subjects with heightened risk for aggression (see Calder et al
2008). Moreover, the temporal properties of this modulation are consistent
with the idea of a reduced functional coupling from the vmPFC to the
amygdala (but not vice versa) in subjects scoring high on reward-drive
(see Passamonti et al 2008).