Brain Stimulation Used Like a Scalpel to Improve Memory

Precise memory is enhanced with targeted non-invasive brain stimulation

Newswise, February 15, 2017 — CHICAGO - Northwestern Medicine scientists showed for the first time that non-invasive brain stimulation can be used like a scalpel, rather than like a hammer, to cause a specific improvement in precise memory.

Precise memory, rather than general memory, is critical for knowing details such as the specific color, shape and location of a building you are looking for, rather than simply knowing the part of town it’s in.

This type of memory is crucial for normal functioning, and it is often lost in people with serious memory disorders.

“We show that it is possible to target the portion of the brain responsible for this type of memory and to improve it,” said lead author Joel Voss, assistant professor of medical social sciences at Northwestern University Feinberg School of Medicine.

“People with brain injuries have problems with precise memory as do individuals with dementia, and so our findings could be useful in developing new treatments for these conditions.”

Red highlights the "core" of the memory network. " Blue indicates where electromagnetic pulses were applied.

By stimulating the brain network responsible for spatial memory with powerful electromagnets, scientists improved the precision of people's memory for identifying locations.

This benefit lasted a full 24 hours after receiving stimulation and corresponded to changes in brain activity.

“We improved people’s memory in a very specific and important way a full day after we stimulated their brains,” Voss said.

The paper was published Jan. 19 in Current Biology.

The research enhances scientific understanding of how memory can be improved using noninvasive stimulation. Most previous studies of noninvasive brain stimulation have found only very general and short-lived effects on thinking abilities, rather than highly specific and long-lasting effects on an ability such as precise memory.

The memory test that showed improvements due to stimulation. 

Subjects studied ~100 objects, each at specific screen location, and were tested for their ability to recall these locations after a delay.The scientists used MRI to identify memory-related brain networks then stimulated them with noninvasive electromagnetic stimulation. Detailed memory tests were used to show that this improved spatial precision memory, and EEG was used to show that these memory improvements corresponded to indicators of improved brain network function.

Other Northwestern authors include first author Aneesha S. Nilakantan, Donna J. Bridge, Elise P. Gagnon and Stephen A. VanHaerents.

The research was supported by grants P50-MH094263, R01-MH106512, and R01-MH111790 from the National Institute of Mental Health, T32-AG20506 from the National Institute on Aging and F32-NS087885 from the National Institute of Neurological Disorders and Stroke, all of the National Institutes of Health.

Women’s Cognitive Decline Begins Earlier Than Previously Believed

 Newswise, February 15, 2017 — UCLA researchers have found that mental sharpness in women begins to decline as early as their 50s. The study, which followed the same group of healthy women for 10 years after menopause, found that their average decline in mental processing ability was 5 percent during the decade-long period.

Cognitive processing speed, which includes speed of perception and reaction, showed an average decline of around 1 percent every two years and verbal memory declined on average around 1 percent every five years.

Previous longitudinal studies in midlife women had failed to consistently detect these cognitive declines.

For this study, the researchers accounted for what are called “practice effects,” which is when repeat testing using the same tests in the same individuals influence the results.

Practice effects mask some effects of the menopause transition. In this way they were able to uncover evidence of declines in two domains of cognitive functioning — processing speed and verbal memory.

The researchers examined data on more than 2,000 healthy women enrolled in the Study of Women’s Health Across the Nation, or SWAN, who were tested regularly over several years to measure cognitive changes. The women were in their 40s when they enrolled in 1996 and were followed every one to two years for a median period of 6.5 years.

Women in their 40s and 50s who find they are forgetting things more often or think they are slower to react may only be experiencing usual aging, analogous to gradual slowing of physical reaction time, running speed, metabolic rate, and other declines that we all experience in midlife.

The authors of the study were Arun Karlamangla, WeiJuan Han, MeiHua Huang and Gail Greendale of UCLA, and Margie Lachman of Brandeis University

The study is published in the journal PLOS ONE.

SWAN has grant support from the National Institutes of Health (NIH),  the National Institute on Aging, the National Institute of Nursing Research and the NIH Office of Research on Women's Health (Grants U01NR004061; U01AG012505, U01AG012535, U01AG012531, U01AG012539, U01AG012546, 01AG012553, U01AG012554, U01AG012495).

Sociology Professor Addresses Caregiving Burden From Personal Perspective

Newswise, February 2, 2017— It’s not every day a researcher draws from their own experiences as the basis for a published study but that’s exactly what Miles Taylor, associate professor of sociology at Florida State University, has done in her latest paper addressing what she calls the structural burden of caregiving.

The study, “The Structural Burden of Caregiving: Shared Challenges in the United States and Canada,” published in the January edition of The Gerontologist, examines the caregiving stress associated with navigating the health care system in the United States and the social care system in Canada.

A call for papers from The Gerontologist prompted Taylor and her colleague Amélie Quesnel-Vallée, sociology professor at McGill University in Quebec, to consider their own experiences caring for aging parents and to see if those experiences exposed gaps in aging literature.

For Taylor and Quesnel-Vallée, the most noticeable void lay in the area of emphasis and quantifiable data on the amount of time caregivers spend negotiating treatment and services for their care recipients.

“Research up until now has really defined caregiving burden in terms of the amount of time and stress it takes to actually provide care to another person — helping with daily tasks and how especially difficult it can be when they need help with things that are very personal, like bathing,” Taylor said.

Taylor said previous models of caregiving burden have done a good job of notating interpersonal stresses, such as strained relationships and the demands in the caregiver’s life.

But what about the time spent negotiating health care systems, getting the care, getting treatments, figuring out when treatments will be covered and under which circumstances? That part of the caregiving burden, Taylor and Quesnel-Vallée say, isn’t well-articulated or measured.

It was 2010 when Taylor began caring for her grandmother, her only living parent, off and on for about 5 years. That was about the same time Quesnel-Vallée began caring for her mother in Canada. The two found their caregiving trajectories and experiences lined up so much, they decided to put their experiences in this paper.

Although they knew providing the direct care would be difficult, they were not prepared for how much time and stress they would spend trying to understand, negotiate and manage medical and related care for their loved ones. They contrasted the two care settings. Ultimately, they concluded that Canada offers more services for older adults and there is more transparency about what is and what is not covered.

However, there were some common themes among the Canadian and American systems. In both systems the researchers found that a great deal of time was spent negotiating and managing care and services but the burden often went unrecognized. They also found in their experience as caregivers that the systems were characterized by discontinuous and fragmented care.

The final common theme researchers noted was the gross potential for inequity for both the caregivers and care recipients.

“We kept telling each other over the course of the past six years, if we felt like this was so difficult and if we had such a hard time, how in the world would other folks begin to deal with this? It must be so much more burdensome,” Taylor said.

Taylor and Quesnel-Vallée felt their education, income and even their race gave them more social currency and health care literacy to help them gain information and access services.

The pair want the paper to not only inform health care professionals and policymakers about the aforementioned issues with the two care systems, but also the caregivers themselves.

“We hope caregivers will understand this part of caregiving, the stress involved in managing care and negotiating services, constitutes caregiving time and stress,” Taylor said. “Often, we felt it wasn’t counted in terms of how much time is spent caring for someone else.”

Through their testimony, Taylor and Quesnel-Vallée also hope other scholars will move forward and try to measure this time and stress related to managing care better. Right now, most surveys only question how much time caregivers take feeding or bathing their care recipient or providing other daily tasks such as taking out the trash.

“I think that now we should increasingly ask how much time and stress did you spend negotiating with medical care, and Medicare, and trying to figure out which services were available and when,” Taylor said.

Taylor says a number of people are experiencing the structural burden of caregiving even though it’s not clearly in the literature yet. They hope caregiving theory can broaden and consider this structural burden, especially considering advanced medical practices are causing people to live longer.

“There was a very recent caregiving report that said over half of caregivers are actually engaged in these kinds of tasks, yet we don’t quantify that,” Taylor said. “We don’t say how much time is this taking up? So that’s what we’re hoping to do, shed more light on it — and I think when you give something a name and a clear theme and definition — that’s when you can get the ball rolling to help people to talk about it more.”