Brain stimulation improves working memory in adults
May 15, 2019
Science Daily/Duke Department of Neurology
Magnetic stimulation of the brain improves working memory, offering a new potential avenue of therapy for individuals living with Alzheimer's disease and other forms of dementia, according to new research from the Duke University School of Medicine.
Healthy younger and older adult participants who received a therapy called repetitive transcranial magnetic stimulation (rTMS) performed better on a memory task than during an rTMS-like placebo in the study, which was published here in PLoS One.
"This study relies on highly individualized parameters, from the selection of the stimulated target, based on fMRI activation, to the selection of the difficulty, titrated according to subjects' performance. Now that we have shown that these specific parameters can improve performance in healthy subjects, we will be able to extend it to populations with memory deficits," said Lysianne Beynel, PhD, a postdoctoral associate in the Department of Psychiatry and Behavioral Sciences.
Working memory is the process of recalling and then using relevant information while performing a task. It's a key component of day-to-day tasks like driving to a new location, making a recipe, or following instructions. Individuals with Alzheimer's disease, which will more than double by 2050, and other forms of dementia, experience progressive loss of working memory and other forms of cognition, leading to a greater risk of injury or death and reducing their ability to function without home care.
Twenty-nine young adults and 18 older adults completed the study, which involved trying to remember and then reproduce a series of letters in alphabetical order. The authors applied either online high-frequency (5Hz) rTMS, or a placebo-like sham over the left prefrontal cortex, an area on the brain responsible for higher executive function. Participants of all ages who received rTMS performed better than those who received the rTMS-like placebo.
"Interestingly, we only saw this effect during when participants were trying their hardest, suggesting a real use-it-or-lose it principle at work here," said co-author Simon W. Davis, PhD. "Contrary to much of what we hear, aging brains have a remarkable capability to remember past events and to use that information in a flexible manner. The brain stimulation applied in our study shows that older adults benefited just as much as the young."
https://www.sciencedaily.com/releases/2019/05/190515130256.htm
Brain stimulation helps younger, not older, adults' memory
March 1, 2018
Science Daily/University of Illinois at Chicago
A study found that while the younger adults showed memory improvement from transcranial direct current stimulation, the older adults did not.
As people grow older their memory tend to get poorer, so finding ways to improve it is an important matter of investigation given the longer contemporary lifespans that people are experiencing.
Recent research has shown that stimulating the brain with a mild electric current, known as transcranial direct current stimulation, can improve memory in both younger and older adults.
In a study published online for a forthcoming special issue on the cognitive neuroscience of aging from the Journals of Gerontology: Psychological Sciences, researchers at the University of Illinois at Chicago tested these outcomes by having younger and older sets of participants -- 48 people between the ages of 18 and 35, as well as 48 adults between the ages of 60 and 79 -- try to learn information and remember 60 face-name pairs.
Some of the study participants were given stimulation, and others received sham, or fake, stimulation. Their memories were tested both immediately after stimulation and again 24 hours later to assess effects on memory the following day.
Ultimately, the researchers found that while the younger adults showed memory improvement from stimulation, the older adults did not.
"On average the amount of improvement that younger adults showed from brain stimulation was a 50 percent improvement in memory," said Eric Leshikar, UIC clinical assistant professor of psychology and corresponding author of the study. "Importantly, we found these memory improvements both immediately after stimulation, as well as after 24 hours, suggesting that brain stimulation can effectively improve memory."
The results contradict findings from previous studies that showed that a slight electoral current through the scalp had a greater effect on cognition for older adults compared to younger adults.
Leshikar says future work will look at whether using different stimulation procedures can help propel older adults to experience memory improvement.
"It very well may be that older adults may show memory improvement from stimulation, but perhaps not under the stimulation procedures we used in this study," he said.
https://www.sciencedaily.com/releases/2018/03/180301094829.htm