Scientists have discovered more about the role of an important brain protein which is instrumental in translating learning into long-term memories.
Writing in Nature Neuroscience, they said further research into the Arc protein's role could help in finding new ways to fight neurological diseases.
The same protein may also be a factor in autism, the study said.
Recent research found Arc lacking in the brains of Alzheimer's patients.
Dr Steve Finkbeiner, professor of neurology and physiology at the University of California, who led the research at Gladstone Institutes, said lab work showed that the role of the Arc protein was crucial.
"Scientists knew that Arc was involved in long-term memory, because mice lacking the Arc protein could learn new tasks, but failed to remember them the next day," he said.
Further experiments revealed that Arc acted as a "master regulator" of the neurons during the process of long-term memory formation.
The study explained that during memory formation, certain genes must be switched on and off at very specific times in order to generate proteins that help neurons lay down new memories.
The authors found that it was Arc that directed this process, from inside the nucleus.
Dr Finkbeiner said people who lack the protein could have memory problems.
"Scientists recently discovered that Arc is depleted in the hippocampus, the brain's memory centre, in Alzheimer's disease patients.
"It's possible that disruptions to the homeostatic scaling process may contribute to the learning and memory deficits seen in Alzheimer's."
The study says that dysfunctions in Arc production and transport could also be a vital player in autism.
The genetic disorder Fragile X syndrome, for example, which is a common cause of both mental disabilities and autism, directly affects the production of Arc in neurons.
The Californian research team said they hoped further research into the Arc protein's role in human health and disease would provide even deeper insights into these disorders and lay the groundwork for new therapeutic strategies to fight them.