Cramming for an exam is not always the best learning strategy. Studies have suggested that learning across several sessions is much more effective. But even after learning something, we tend to forget it with time and age. Molecular studies have indicated that certain signaling proteins that regulate synaptic strength may underlie learning, memory, and forgetfulness. Genoux et al. confirm through rodent behavioral studies that three of these molecular suspects are indeed the culprits. When protein phosphatase 1 (PP1) was genetically inhibited in mice, animals exhibited enhanced learning, that is, long intervals between learning episodes were no longer needed. This also correlated with increased activation of a transcription factor called cAMP-dependent response element binding (CREB) protein and of Ca2+/calmodulin-dependent kinase II (CaMKII), molecules implicated in long- and short-term memory, respectively. Memory tests of these mice also indicate that these same signaling molecules may also underlie forgetfulness that occurs with time and age.
D. Genoux, U. Haditsch, M. Knobloch, A. Michalon, D. Storm, I. M. Mansuy, Protein phosphatase 1 is a molecular constraint on learning and memory. Nature 418, 970-975 (2002). [Online Journal]