Featured Research

from universities, journals, and other organizations

Parkinson's disease brain rhythms detected: Finding suggests better way to monitor, treat disease with deep brain stimulation

Date:
March 4, 2013
Source:
University of California - San Francisco
Summary:
Scientists have discovered how to detect abnormal brain rhythms associated with Parkinson's by implanting electrodes within the brains of people with the disease.

A team of scientists and clinicians at UC San Francisco has discovered how to detect abnormal brain rhythms associated with Parkinson's by implanting electrodes within the brains of people with the disease.

The work may lead to developing the next generation of brain stimulation devices to alleviate symptoms for people with the disease.

Described this week in the journal Proceedings of the National Academy of Sciences (PNAS), the work sheds light on how Parkinson's disease affects the brain, and is the first time anyone has been able to measure a quantitative signal from the disease within the cerebral cortex -- the outermost layers of the brain that helps govern memory, physical movement and consciousness.

"Normally the individual cells of the brain are functioning independently much of the time, working together only for specific tasks," said neurosurgeon Philip Starr, MD, PhD, a professor of neurological surgery at UCSF and senior author of the paper. But in Parkinson's disease, he said, many brain cells display "excessive synchronization," firing together inappropriately most of the time.

"They are locked into playing the same note as everyone else without exploring their own music," Starr explained. This excessive synchronization leads to movement problems and other symptoms characteristic of the disease.

The new work also shows how deep brain stimulation (DBS), which electrifies regions deeper in the brain, below the cortex, can affect the cortex, itself. This discovery may change how DBS is used to treat Parkinson's and other neurologically based movement disorders, and it may help refine the technique for other types of treatment.

Functions Like a Pacemaker for the Brain

Over the last decade, doctors at UCSF and elsewhere have turned to deep brain stimulation to help people with Parkinson's disease and movement disorders like essential tremor and primary dystonia, an extremely debilitating conditionthat causes painful, twisting muscle spasms.

In addition, deep brain stimulation is now being explored to treat psychiatric diseases like depression and obsessive-compulsive disorder.. Last year a team at UCLA showed that electrical stimulation of the temporal lobe in patients during learning activities helped them recall specific types of spatial information.

Similar to putting a pacemaker inside a heart patient's chest, deep brain stimulation requires a neurosurgeon to implant electrodes inside tiny parts of the brain, to deliver electrical current.

In Parkinson's these electrodes are generally implanted in people who have mid-stage disease and cannot obtain full benefit from commonly used drugs due to complications -- about 10- to 15-percent of all patients with the disease. For them, deep brain stimulation can free them of severe mobility problems and other symptoms, helping them live with much improved motor function for many years. Eventually the progressive nature of Parkinson's disease overwhelms the ability of deep brain stimulation to alleviate symptoms.

However, while doctors have witnessed for years the sometimes miraculous recovery of function that can come with one of these surgeries, said Starr, the odd thing is that nobody understands exactly why deep brain stimulation works. The prevailing hypothesis is that it alleviates symptoms by overriding the abnormal, "bad" brain circuitry, much like turning down the noise can increase the fidelity of a musical recording.

The new work supports this hypothesis. Working with 16 patients with Parkinson's disease and nine with cervical dystonia undergoing neurosurgical treatment over the past three years, Starr and his colleagues showed clearly how to detect excessive brain synchronization at the surface of the brain in people with Parkinson's disease and how deep brain stimulation can return those surface cells to their independent state.

Patients in the study consented to have temporary, flexible electrodes placed on their brain surface for a few hours during surgery, in addition to having the permanent deep stimulating electrodes implanted for long-term therapy.

The first author on the study is Coralie de Hemptinne, PhD, a postdoctoral fellow in Starr's laboratory. Patients were managed before and after surgery by study co-authors Jill Ostrem, MD, and Nicholas Galifianakis, MD, neurologists in the UCSF Surgical Movement Disorders (SMD) Center.

For controls, they compared the surface brain recordings of those 25 patients with nine more people who were undergoing surgery for epilepsy and did not have abnormal brain patterns while they were not having seizures.

The ability to monitor excessive brain synchronization on the surface of the brain points the way to next-generation brain stimulators that would be more sophisticated, Starr said. Right now most devices implanted into patients deliver continuous electrical stimulation. But modern heart pacemakers deliver jolts only when needed.

If DBS implants could be made to detect an abnormal signal in the surface of the brain and deliver their electrical stimulation only when needed, they might function better, require much less work from clinicians to adjust stimulator settings, and be able to automatically adjust stimulation levels to match changes in patient's movement symptoms. Symptoms can often vary greatly throughout the day, but existing DBS devices have no way to adjust themselves for changing conditions in the patient's brain.

The next step, said Starr, will be to find ways to detect these signals automatically with an implanted DBS device so that the electrical brain stimulator would respond automatically and flexibly to a patient's needs.

UCSF, Starr, and co-investigators hold a provisional patent titled "Detection of a cortical biomarker in movement disorders using a non-penetrating electrode."


Story Source:

The above story is based on materials provided by University of California - San Francisco. Note: Materials may be edited for content and length.


Cite This Page:

University of California - San Francisco. "Parkinson's disease brain rhythms detected: Finding suggests better way to monitor, treat disease with deep brain stimulation." ScienceDaily. ScienceDaily, 4 March 2013. <www.sciencedaily.com/releases/2013/03/130304151809.htm>.
University of California - San Francisco. (2013, March 4). Parkinson's disease brain rhythms detected: Finding suggests better way to monitor, treat disease with deep brain stimulation. ScienceDaily. Retrieved July 26, 2014 from www.sciencedaily.com/releases/2013/03/130304151809.htm
University of California - San Francisco. "Parkinson's disease brain rhythms detected: Finding suggests better way to monitor, treat disease with deep brain stimulation." ScienceDaily. www.sciencedaily.com/releases/2013/03/130304151809.htm (accessed July 26, 2014).

Share This




More Mind & Brain News

Saturday, July 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

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
Can Watching TV Make You Feel Like A Failure?

Can Watching TV Make You Feel Like A Failure?

Newsy (July 24, 2014) A study by German researchers claims watching TV while you're stressed out can make you feel guilty and like a failure. 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