“…Although the dorsal hippocampus is well equipped with projections from the sensory cortices, providing contextual information, only the ventral hippocampus has direct connections with extrahippocampal structures implicated in formation, processing, and expression of conditioned fear, such as amygdala (e.g., Cahill et al, 1999;Fanselow and LeDoux, 1999), nucleus accumbens (e.g., Riedel et al, 1997;Haralambus and Westbrook, 1999;Murphy et al, 2000;Pezze et al, 2001bPezze et al, , 2002b, and prefrontal cortex (e.g., Lacroix et al, 2000;Feenstra et al, 2001;Pezze et al, 2001aPezze et al, , 2002a2003). For example, it has been proposed that context and US are associated via synaptic plasticity in the projection from the ventral hippocampus to the basolateral amygdala (Maren and Fanselow, 1995;Anagnostaras et al, 2001). Information about the contextual representation formed with participation of dorsal hippocampal mechanisms can reach the ventral hippocampus via direct intrahippocampal connections between dorsal and ventral hippocampus or via the parahippocampal cortices, in particular the entorhinal cortex.…”