At its most fundamental level, a memory is an increase in
synaptic strength that persists over time. That persistence requires synthesis
of a specific set of synaptic proteins, a process regulated by so-called
Cytoplasmic Polyadenylation Element Binding (CPEB) proteins. The remarkable
feature of these proteins is their prion-like nature. Their conversion from
monomers to oligomers, via stacking of their prion domains, is essential to the
long-term maintenance of synaptic memory.