Featured Research

from universities, journals, and other organizations

Sleep improves memory in people with Parkinson's disease

Date:
August 21, 2012
Source:
Emory University
Summary:
People with Parkinson's disease performed markedly better on a test of working memory after a night's sleep, and sleep disorders can interfere with that benefit, researchers have shown.

People with Parkinson's disease performed markedly better on a test of working memory after a night's sleep, and sleep disorders can interfere with that benefit, researchers have shown.

While the classic symptoms of Parkinson's disease include tremors and slow movements, Parkinson's can also affect someone's memory, including "working memory." Working memory is defined as the ability to temporarily store and manipulate information, rather than simply repeat it. The use of working memory is important in planning, problem solving and independent living.

The findings underline the importance of addressing sleep disorders in the care of patients with Parkinson's, and indicate that working memory capacity in patients with Parkinson's potentially can be improved with training. The results also have implications for the biology of sleep and memory.

The results were published this week in the journal Brain.

"It was known already that sleep is beneficial for memory, but here, we've been able to analyze what aspects of sleep are required for the improvements in working memory performance," says postdoctoral fellow Michael Scullin, who is the first author of the paper. The senior author is Donald Bliwise, professor of neurology at Emory University School of Medicine.

The performance boost from sleep was linked with the amount of slow wave sleep, or the deepest stage of sleep. Several research groups have reported that slow wave sleep is important for synaptic plasticity, the ability of brain cells to reorganize and make new connections.

Sleep apnea, the disruption of sleep caused by obstruction of the airway, interfered with sleep's effects on memory. Study participants who showed signs of sleep apnea, if it was severe enough to lower their blood oxygen levels for more than five minutes, did not see a working memory test boost.

In this study, participants took a "digit span test," in which they had to repeat a list of numbers forward and backward. The test was conducted in an escalating fashion: the list grows incrementally until someone makes a mistake. Participants took the digit span test eight times during a 48-hour period, four during the first day and four during the second. In between, they slept.

Repeating numbers in the original order is a test of short-term memory, while repeating the numbers in reverse order is a test of working memory.

"Repeating the list in reverse order requires some effort to manipulate the numbers, not just spit them back out again," Scullin says. "It's also a purely verbal test, which is important when working with a population that may have motor impairments."

54 study participants had Parkinson's disease, and 10 had dementia with Lewy bodies: a more advanced condition, where patients may have hallucinations or fluctuating cognition as well as motor symptoms. Those who had dementia with Lewy bodies saw no working memory boost from the night's rest. As expected, their baseline level of performance was lower than the Parkinson's group.

Participants with Parkinson's who were taking dopamine-enhancing medications saw their performance on the digit span test jump up between the fourth and fifth test. On average, they could remember one more number backwards. The ability to repeat numbers backward improved, even though the ability to repeat numbers forward did not.

Patients needed to be taking dopamine-enhancing medications to see the most performance benefit from sleep. Patients not taking dopamine medications, even though they had generally had Parkinson's for less time, did not experience as much of a performance benefit. This may reflect a role for dopamine, an important neurotransmitter, in memory.

Scullin and Bliwise are planning an expanded study of sleep and working memory, in healthy elderly people as well as patients with neurodegenerative diseases.

"Many elderly people go through a decline in how much slow wave sleep they experience, and this may be a significant contributor to working memory difficulties," Scullin says.

The research was supported by the National Institute of Neurological Disorders and Stroke (R01 NS050595) and the National Institute of Aging (F32 AG041543).


Story Source:

The above story is based on materials provided by Emory University. The original article was written by Quinn Eastman. Note: Materials may be edited for content and length.


Journal Reference:

  1. M. K. Scullin, L. M. Trotti, A. G. Wilson, S. A. Greer, D. L. Bliwise. Nocturnal sleep enhances working memory training in Parkinson's disease but not Lewy body dementia. Brain, 2012; DOI: 10.1093/brain/aws192

Cite This Page:

Emory University. "Sleep improves memory in people with Parkinson's disease." ScienceDaily. ScienceDaily, 21 August 2012. <www.sciencedaily.com/releases/2012/08/120821115003.htm>.
Emory University. (2012, August 21). Sleep improves memory in people with Parkinson's disease. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2012/08/120821115003.htm
Emory University. "Sleep improves memory in people with Parkinson's disease." ScienceDaily. www.sciencedaily.com/releases/2012/08/120821115003.htm (accessed July 28, 2014).

Share This




More Mind & Brain News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Losing Sleep Leaves You Vulnerable To 'False Memories'

Losing Sleep Leaves You Vulnerable To 'False Memories'

Newsy (July 27, 2014) A new study shows sleep deprivation can make it harder for people to remember specific details of an event. Video provided by Newsy
Powered by NewsLook.com
University Quiz Implies Atheists Are Smarter Than Christians

University Quiz Implies Atheists Are Smarter Than Christians

Newsy (July 25, 2014) An online quiz from a required course at Ohio State is making waves for suggesting atheists are inherently smarter than Christians. Video provided by Newsy
Powered by NewsLook.com
Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

AFP (July 24, 2014) A so-called drugs rehab 'clinic' is closed down in Pakistan after police find scores of ‘patients’ chained up alleging serial abuse. Duration 03:05 Video provided by AFP
Powered by NewsLook.com
New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins