, 2010), object-place (Lee and Solivan, 2008) and fear memories (Corcoran and Quirk, 2007), learned 1 or 2 days before testing. Despite strong evidence that mPFC http://www.selleckchem.com/products/isrib-trans-isomer.html is needed for both recent and remote memory, the many studies showing greater involvement of mPFC in remote memory cannot be ignored (see Table S1 available online). The most straightforward explanation is that mPFC participates in recent memory but plays an even greater role in retrieval of remote memory. Indeed, one study of contextual fear memory after mPFC lesion found a weak but significant impairment in recent memory and a stronger impairment in remote memory ( Quinn et al., 2008).

While our framework does not predict this phenomenon, it can be extended to accommodate the data. During the recall of recent memory, the role of mPFC is to represent Cell Cycle inhibitor context, events and responses while the mapping between them is stored within the hippocampus. During remote recall, on the other hand, the mPFC both represents and stores context-event-response mappings while the

hippocampus becomes disengaged. Because mPFC serves for both storage and representation, the brain may be less able to compensate for its loss during remote retrieval than during recent. While the preceding section emphasized the role of mPFC in the retrieval of long-term memories, there is now considerable evidence that mPFC plays an important role in the consolidation of a wide range of memories. These studies demonstrate that activity in mPFC immediately after a task is needed for retrieval on subsequent days. Evidence that mPFC is needed for stabilization of recently acquired memories spans a wide

range of appetitive tasks. One study used an odor-reward association, acquired in just a few trials. When disruptive agents were injected into mPFC immediately after learning, subsequent testing 48 hr later revealed a severe memory impairment (Carballo-Márquez et al., 2007; Tronel et al., 2004; Tronel and Sara, 2003). Similar effects have been observed in lever-press for reward (Izaki et al., 2000), socially transmitted food preference (Carballo-Márquez et al., 2009), object recognition (Akirav and Maroun, 2006), and the Morris water maze (Leon et al., 2010). Activity in mPFC immediately after learning is also important for unless the consolidation of fear memory. For example, interfering with mPFC plasticity immediately after trace fear conditioning (i.e., with a delay between tone and shock) has been shown to cause deficits in memory retrieval both 24 and 72 hr later (Runyan et al., 2004); however, the results for simple tone-shock fear conditioning are equivocal (Morrow et al., 1999; Zhao et al., 2005). Like trace fear conditioning, the consolidation of contextual fear conditioning is also dependent upon mPFC ( Zhao et al., 2005). Contextual fear has also been examined using inhibitory avoidance.