- A person’s working memory is critically important for functioning in daily life.
- Older people and those who have Parkinson’s disease, dementia, or who have had a stroke may experience a degradation of their working memory.
- A new study finds that combining cognitive exercises and electrical brain stimulation can substantially strengthen working memory.
A person’s working memory may decline with age or if they have dementia, Parkinson’s disease, or have had a stroke. When this occurs, the loss can affect their day-to-day quality of life, turning even simple tasks into often-demoralizing challenges.
Prof. Gail Eskes explained working memory to Medical News Today, and why it is so important.
“Working memory is the brain’s mental scratchpad,” she noted, “and it can be used to keep in mind, and work with, a variety of different types of information.”
“For example,” she offered, “you use working memory when you are keeping in mind someone’s phone number once you’ve looked it up, or keeping in mind an image of a map of the city in order to plan a way to get to your destination.”
“Your working memory ability is important for all kinds of activities,” said Prof. Eskes, “such as reading a newspaper, doing math at a restaurant to figure out a tip, making decisions, and problem-solving.”
Prof. Eskes is a member of the Department of Psychiatry, Department of Psychology and Neuroscience, and Division of Neurology at Dalhousie University in Halifax, Nova Scotia, Canada. She is the co-author of a new study describing a possible means of helping people regain their working memory.
Researchers from Dalhousie, the University of Trento in Italy, and Birmingham University in the United Kingdom contributed to the study, which found that cognitive training alongside transcranial direct current stimulation significantly strengthens working memory.
Dr. Jacqueline Becker, a clinical neuropsychologist and health services researcher at Mount Sinai’s Icahn School of Medicine in New York, who was not involved in the study, told MNT that “with working memory training, the brain can rewire and reorganize itself as a result of repeated training and practice.”
“This is based on neuroplasticity, which refers to the brain’s ability to change and adapt as a result of an experience,” Dr. Becker explained.
Similarly, she said, “[t]ranscranial direct current stimulation can also affect the brain’s plasticity, by activating and increasing activity within specific brain networks.”
In the study, the direct stimulation is provided by a light 2 milliAmpère electric current applied to the scalp.
The study appears in Frontiers in Aging Neuroscience.
The study authors refer to their system as COGNISANT, which stands for “cognitive needs and skills training.”
The study’s senior author is assistant professor Dr. Sara Assecondi of the Center for Mind/Brain Sciences at the University of Trento. She explained how the two aspects of COGNISANT work together: “In our study, working memory training and brain stimulation target the same brain area — the right dorsolateral prefrontal cortex — an area associated with processing spatial information.”
“The repetition of the same cognitive task, at a level of difficulty that is just enough to be challenging but still engaging, promotes brain plasticity […] Brain stimulation further boosts plasticity, giving cognitive training an extra ‘kick,’ particularly effective in those individuals who need it more.”
– Dr. Sara Assecondi
The memory training proposed in the study takes place online. Prof. Eskes, who developed it, explained how it works.
“With our software, one can train using a range of information, like hearing and working with numbers or words, or seeing and working with items in space, or landscape images, etc,” she told MNT.
“This training software was designed to help any adult who wants to enhance their capacity or efficiency of their working memory. It can be done anywhere using a computer with access to the internet,” she noted.
Participants in the study ranged in age from 55 to 76 years, a span that includes potential beneficiaries who may possess a range of online skills.
“We have tested it with adults and patients of all adult ages, and usually the training can be done independently, although different people have different levels of comfort with computer use,” said Prof. Eskes.
“For this study,” explained Prof. Eskes, “we used a therapeutic game we have named ‘N-Igma,’ and it uses the ‘n-back’ technique in which the players must keep track of a stream of information and indicate when they see a match to an item they saw ‘n’ turns ago,” where “n” represents an unspecified numerical value.
“The number of items they have to keep track of adapts to their performance, so they are working at a challenging, but not impossible, level. To keep it game-like and interesting, we also give them lots of feedback, and they can keep track of their score as they go along,” the researcher added.
“These therapeutic games are intensive and challenging, but we also try to keep it engaging and fun,” Prof. Eskes told us.
“We develop approaches to promote healthy aging, so our technique really may be useful to anyone who starts to experience some kind of memory decline,” said Dr. Assecondi.
“Although characterized by huge variability, the older healthy adults are the more likely they are to show a lower working memory, and that is when the combination of working memory training and brain stimulation is more effective,” she told us.
“From the results of the study, it can be inferred that older adults (greater than 69 years of age) with executive dysfunction may derive the most benefit,” noted Dr. Becker.
It may also be that COGNISANT is most appropriate for people whose working memory has declined beyond a certain threshold, although what that threshold might be is unclear for now.
“With the data available,” said Dr. Assecondi, “it’s difficult to estimate an ‘optimal’ level of working memory loss for the approach to be effective. Indeed, this would be important information for future development and use within the healthy population.”
“We would need to collect a large amount of data to obtain a fair representative sample of the healthy population, and this is indeed something we would be interested in exploring,” she added.
“With my group,” she said, “using state-of-the-art statistical approaches, I am working on ways to predict the effectiveness of cognitive intervention from baseline abilities, but we are still in the early stage.”
“There is still much research to do,” acknowledged Dr. Assecondi, “but from our work and that of other laboratories around the world, we know that the combination of cognitive training and brain stimulation holds promise, not only in slowing down the cognitive decline of healthy adults, but also in clinical populations.”
“I hope to contribute to developing an effective low-cost technique that can be used at home and tailored to the individual’s specific needs, reaching those who would otherwise be unable to access such technology,” she said.
The authors are now working with the University of Birmingham and Dalhousie University to identify partners who can help bring COGNISANT to market.
“Home-care technology will ultimately allow individuals to take therapy into their own hands,” concluded Dr. Assecondi, “empowering them to age according to their terms.”