THURSDAY, June 16 (HealthDay News) -- Your ability to remember things may vary according to levels of certain brain waves at a given moment, a new study suggests.

"It's been assumed that the process of retrieving a memory is cued by an external stimulus, but we found that the levels of brain activity before items came up were correlated with memory," Charan Ranganath, a professor with the Center for Neuroscience and the psychology department at the University of California, Davis, said in a university news release.

The researchers measured levels of brain waves called theta oscillations in the brains of volunteers during a test in which they had to memorize a series of words with a related context. Theta waves are associated with active monitoring by the brain.

The volunteers did better on the memory test if they had high levels of theta waves immediately before they were asked to remember a word, the study found.

The findings, published June 13 in the Proceedings of the National Academy of Sciences, challenge the belief that the brain is waiting to react to the external world, according to Ranganath.

The research team is now investigating whether it's possible for people to deliberately put their brain in a better state for memory recall -- research that they say could lead to new treatments for memory loss.

More information

The American Academy of Family Physicians has more on the brain and memory.