Trying to commit something important to memory? Your best bet is to relate that bit of information to something meaningful like a story rather than simply repeating it again and again, a paper from Baycrest Health Sciences reports.

Image credits Andrew Martin.

While it’s relatively easy to put something in your short-term memory, the data encoded this way tends to degrade pretty fast. So if you need to keep a hold of this information, you need to make sure that it stays “fresh” until the brain copy-pastes it into your more durable long-term memory. Us laymen go about it by repeating the tidbit on and on in our mind until it’s seared into memory, but that seems to not be the best way of going about it.

When we are learning new information, our brain has two different ways to remember the material for a short period of time, either by mentally rehearsing the sounds of the words or thinking about the meaning of the words,” says Dr. Jed Meltzer, lead author and neurorehabilitation scientist at Baycrest’s Rotman Research Institute. “Both strategies create good short-term memory, but focusing on the meaning is more effective for retaining the information later on.”

“Here’s a case where working harder does not mean better.”

Meaningful memory

To reach this conclusion, the team looked at the different parts of the brain involved in the two types of short-term memory formation. They recruited 25 healthy adults and recorded their brain activity while they listened to a list of words and sentences. Participants were asked to hold the information in their short-term memory for a few seconds then recite them back, again while their brainwaves were being recorded.

After this, participants were taken to a different room and tested to see how much of the information they could recall. Using the brain scans, the team could tell whether each participant used sound repetition or meaning association to commit the words to memory and correlate that to their memory quality.

Overall, participants who used the sound repetition method to commit words to memory fared worse in the final step of the study compared to those who used meaning to fix short-term memory. The findings are consistent with what high-profile memory champions report about their experience, who create stories packed with meaning to remember random information, such as the order in a deck of cards. The authors explain this happens because there are “distinct neural resources for phonological and semantic maintenance”, with sound-repetition processes demanding much more of your brain’s processing power.

Apart from exploring the little understood semantic process of memory encoding, the team’s work also helps offer some pointers from people who are struggling with memory encoding following brain damage.

“When people have brain damage from stroke or dementia, one of the mechanisms may be disrupted. People could learn to compensate for this by relying on an alternate method to form short-term memories,” Dr. Meltzer says.

The best method seems to be the one which passed the test of time with flying colors: carry a pad around and try to affix the memory until you get a chance to write it down, he adds.

Next, the team plans to use their findings to see if targeted brain stimulation can be used to boost short-term memory performance in stroke patients.

The paper “Electrophysiological signatures of phonological and semantic maintenance in sentence repetition” has been published in the journal NeuroImage.