Elevated Arc/Arg 3.1 protein expression in the basolateral amygdala following auditory trace-cued fear conditioning- Chau- 2013

A: Trace     B: Backward     C: Delay

        From the amygdala

This is the first study examining amygdala activation in closer detail following trace fear associative learning. 
The present experiments demonstrate that the amygdala, specifically the BLA, is activated following trace fear conditioning. 
Activation was not found in the CeA or the LA following trace fear conditioning compared to backward-conditioned, delay-conditioned and naïve mice, suggesting that the BLA plays a more critical role in trace fear associative learning than delay fear associative learning. 
Additionally, findings from this study demonstrate that delay-conditioned mice exhibited more Arc expression in the LA compared to any of the other conditioned groups and controls, suggesting that delay fear conditioning taps into an underlying pathway different from trace fear conditioning. 
Together, these findings suggest that the underlying pathway and thus possible neuronal mechanisms for acquisition and subsequent consolidation for trace fear associations are more similar to contextual fear associations than delay fear associations.