The earliest memories after conditioning may be represented by coexisting traces within three nodes of the network—the PNs of the ALs, the α′/β′ MBNs, and the GABAergic APL neurons. It seems possible that because the APL neurons may provide GABAergic innervation of the α′/β′ MBNs, that these two memory traces are PCI-32765 solubility dmso interrelated with one another. Because the earliest detectable changes after conditioning were discovered in these three nodes, it is also possible that the process of acquisition occurs within one or all of these nodes, although

it is not yet possible to exclude acquisition occurring in an alternative node with rapid transfer of the acquired information to these nodes. An intermediate temporal phase of memory may be represented by the memory trace observed in the DPM neurons, given its emergence

and disappearance across the time window that generally defines ITM at the behavioral level. Long-term and protein synthesis-dependent memory may be represented by two (or three, if one counts the increased dendritic protein synthesis in the AL), temporally overlapping memory traces in two other nodes of the olfactory nervous system—the α/β MBNs and the γ MBNs. Provisionally, we have named the memory traces occurring in these nodes as a long-term and a late-phase, long-term memory trace, respectively. Thus, an emerging model to explain Selleck DAPT temporal phases of memory is that these forms of memory are underlain by multiple memory traces that form at discrete Bumetanide times after conditioning in discrete nodes of the olfactory nervous system. The evidence that these memory traces are truly related to behavioral memory ranges from fair to exceptionally strong. The evidence tying the APL and PN traces to STM resides in their coincidence in time after conditioning and in the requirement for a temporal association of the CS and US. In other words, training protocols that decouple the

presentation of the CS and US like backward conditioning, CS-only, US-only, etc., fail to generate short-term behavioral memory and fail to generate the memory traces. Therefore, the memory traces cannot be assigned as emerging from nonassociative, experience-dependent plasticity. In addition to time window coincidence and training protocol-dependence, the DPM memory trace is tied to ITM with results from experiments that block synaptic transmission from these neurons and ascertain the effects of the blockage on later memory. As described above, blocking synaptic transmission over the time window of 30- < 150 min (the endpoint has not yet been accurately established) after conditioning impairs 3 hr memory. This time window is very similar to the time window over which the DPM trace is detectable (30-70 min).