A different recruitment of the lateral and basolateral amygdala promotes contextual or elemental conditioned association in Pavlovian fear conditioning.
Convergent data suggest dissociated roles for the lateral (LA) and basolateral
(BLA) amygdaloid nuclei in fear conditioning, depending on whether a discrete
conditioned stimulus (CS)-unconditional stimulus (US) or context-US association
is considered. Here, we show that pretraining inactivation of the BLA selectively
impaired conditioning to context. In contrast, inactivation of the LA disrupted
conditioning to the discrete tone CS, but also either impaired or enhanced
contextual conditioning, depending on whether the context was in the foreground
or in the background. Hence, these findings refine the current model of the
amygdala function in emotional learning by showing that the BLA and the LA not
only differentially contribute to elemental and context-US association, but also
promote, through their interaction, the most relevant of these two associations.