It should come as no surprise to anyone who's ever forgotten a friend's birthday or been unable to remember a name, but it's easier to lose or damage a memory than it is to enhance one.

A new report in the journal Science, however, reveals that an increase of PKMzeta, a protein that Discover Magazine calls the "engine of memory," might actually help strengthen old memories -- long after they've been formed.

Study co-author Dr. Todd Sacktor told TIME:

What's new and exciting and frankly a little unexpected is that [increasing] PKMzeta did what nothing else has ever been shown to do before: take an old, faded, weak memory and make it stronger.

The protein in question -- PKMzeta -- acts by strengthening the bond between neurons in the brain, creating a network of connections that Discover describes as the "physical embodiment of our memories." Researchers surmised that by upping the level of the protein in rats (which they did by creating a virus that expressed the gene for the protein and injecting it into their neocortexes), they might be able to improve memory.

So what type of memories do rats actually have? Mainly those associated with tastes, like Saccharine and salt, WIRED reports. In addition scientists conducted CTA or "conditioned taste aversion" memory training, which is what it sounds like: exposing rats to an unpleasant, nausea-inducing drug.

What they found was startling: A week after the rats had undergone CTA, scientists injected them with the PKMzeta protein. Then a week after that, WIRED reports, they tested their memory. Their findings? Rats with more of the protein had better memory retention, which means they improved their memories long after their initial formation.

This, the study's authors conclude, means that "PKMzeta is a potential target not only for memory blockers, which may be useful, for example in treating post-traumatic stress) but also for novel types of memory enhancers in the treatment of amnesia and cognitive decline."

Another promising development in memory preservation research was published earlier today in the journal Stem Cells. Researchers at Northwestern University were able to use embryonic stem cells to make forebrain cholinergic neurons, or BFCNs, the type of neurons that die off early in Alzheimer's patients.

With this success, the BBC reports, scientists have now given themselves an enormous supply of neurons for research, which means they can examine why BFCNs perish in the face of Alzheimer's Disease and what can be done to combat it.

Professor Clive Ballard, Director of Research at the UK's Alzheimer's Society, issued the following statement, calling the discovery a major step forward in developing Alzheimer's research:

For the first time researcher have worked out how to transform stem cells into a specific type of nerve cell that is key in the development of the disease ... We now need further research to find out whether these stem cells actually work in the brain.