Many of us have mixed up details, forgotten something, or remembered things that never really happened. Our memories aren't the most reliable because we all perceive things differently. However, researchers at Radboud University Medical Center in the Netherlands have found specific brain training exercises could double our memory capacity.
"After training we see massively increased performance on memory tests," says first author Martin Dresler, assistant professor of cognitive neuroscience at Radboud, in a statement.
Memory athletes, also known as memory masters, are able to recall and recite long lists of random numbers, facts, dates, and other information. They do this by using loci or memory palace, a technique tied to ancient Greece and Rome, where trainees make an imaginary journey through a place they know well, like their home. Each location within the home is used as a visual prompt to store the information the trainee is trying to recall.
Dresler and his colleagues, including Boris Nukolai Kondrad, a neuroscientist and memory athlete with two world records and a Guinness Book of World Records holder, sought to explore brain connectivity patterns among memory masters, whether they could improve memory via loci in people with typical memory skills, and if this led to any pattern changes.
First, the researchers scanned the brains of 23 of the world's most successful memory masters using functional magnetic resonance imaging (fMRI) to determine if there were any differences in brain connectivity patterns between them and people of a similar age with a similar IQ. In other words, they assessed whether brain regions worked differently between both groups. Subtle differences were found across a large number of brain regions, but there wasn't a single region that stood out.
The memory athletes were not born with these extraordinary memory skills.
Dresler noted: "They, without a single exception, trained for months and years using mnemonic strategies to achieve these high levels of performance."
Since brain connectivity is flexible, the researchers recruited 51 people with typical memory skills to explore the effects of brain training on recollection. They were split into three groups: two training groups — one short-term memory training without loci, and one that used loci training; and a third group that did not train. The short-term memory group did practices, such as remembering sequences, similar to the game Concentration. Meanwhile, the loci group were taught a systematic way to remember lists.
Individuals in training groups received six weeks of training for 30 minutes a day. Researchers performed another brain scan to assess any differences in brain connectivity.
The findings revealed those who trained using loci showed significant improvement in recalling lists of words. Prior to training, these individuals could remember an average of 26 and 30 out of 70. After training, they remembered more than 60. Brain scans of this group also showed changes in brain connectivity, which researchers hypothesize could be the basis of increased memory. The brain connectivity patterns of this group began to resemble those of memory athletes compared to scans taken before training.
Meanwhile, those who received no training only recalled 7 more words. Individuals who did short-term training still showed improvements in recall. Fast forward 4 months later, those with loci training continued to show progress, recalling over 22 more words than before the training.
"Once you are familiar with these strategies and know how to apply them, you can keep your performance high without much further training," said Dresler.
The researchers then investigated how connectivity patterns in the brains of memory masters affected their ability to recall information. A total of 25 connections were observed, with two brain regions being the hubs of connectivity: the medial prefrontal cortex, which is active when we relate new knowledge to pre-existing knowledge; and the right dorsal lateral prefrontal cortex, which is involved in how we learn strategically. However, there's still more to learn about the differences in these patterns and how they influence memory.
The study shows how the human brain is very flexible and can be reshaped. A 2011 study in the Journal of Vision believes we remember things that are more meaningful to us, or if we can connect it to other knowledge (i.e., loci method). It seems that memory is all about context.
Source: Dresler M, Shire WR, Konrad BN et al. Mnemonic training reshapes brain networks to support superior memory. Neuron. 2017.