Featured Research

from universities, journals, and other organizations

Independent Brain Networks Control Human Walking

Date:
August 14, 2007
Source:
Kennedy Krieger Institute
Summary:
Researchers discovered that there are separate adaptable networks controlling each leg and there are also separate networks controlling leg movements, e.g., forward or backward walking. These findings are contrary to the currently accepted theory that leg movements and adaptations are directed by a single control circuit in the brain.

Researchers at the Kennedy Krieger Institute in Baltimore, Maryland found that there are separate adaptable networks controlling each leg and there are also separate networks controlling leg movements, e.g., forward or backward walking.

Related Articles


These findings are contrary to the currently accepted theory that leg movements and adaptations are directed by a single control circuit in the brain. The ability to train the right and left legs independently opens the door to new therapeutic approaches for correcting walking abilities in patients with brain injury (e.g., stroke) and neurological disorders (e.g., cerebral palsy and multiple sclerosis).

Using a split-belt treadmill to separately control the legs, Kennedy Krieger researchers Dr. Amy Bastian and Julia Choi studied forty healthy adults and tracked each person’s ability to learn various walking exercises. Utilizing specialized computer software and infrared tracking devices placed on key joints, researchers found subjects could store different walking patterns for forward versus backward walking simultaneously, with no interference between the two, revealing that separate brain systems control the two directions of walking.

Surprisingly, people could also walk easily with one leg moving forward and the other backward, a pattern referred to as “hybrid walking.” Adaptation of hybrid walking, in which varying speeds were applied to legs walking in opposite directions, was found to interfere with subsequent “normal” forward and backward walking. The combined results demonstrate there are distinct brain modules responsible for right/forward, right/backward, left/forward and left/backward walking. Most significantly, these modules can be individually trained, which would be critical for rehabilitation focused on correcting walking asymmetries produced by brain damage.

“The notion that we can leverage the brain’s adaptive capacity and effectively ‘dial in’ the patterns of movement that we want patients to learn is incredibly exciting,” said Dr. Amy Bastian, senior study author and Director of the Motion Analysis Laboratory at the Kennedy Krieger Institute. “These findings significantly enhance our understanding of motor skills, effective therapeutic approaches and the true adaptive nature of the brain.”

The walking adaptations studied here represent a form of short term learning from practicing on this unusual treadmill. Investigators set different speeds for each belt of the treadmill causing subjects to walk in an abnormal limping pattern. However, within 15 minutes subjects adapted and learned to walk smoothly with a normal pattern and rhythm, as verified by computer models.

This indicates that the phenomenon of brain plasticity can occur in short intervals. When subjects returned to normal conditions (same speed for the two legs), this adaptation caused an after-effect that resulted in a limp that lasted for five-to-ten minutes as they “unlearned” the correction. Regardless of how hard subjects tried, they were unable to stop this after-effect, because walking patterns are controlled by automatic brain systems that recalibrate themselves according to current conditions.

“As we understand more about the way the brain learns, relearns and adapts in relation to motor skills, physical therapy professionals have a vastly expanding toolbox from which to tailor therapeutic interventions,” explains Gary Goldstein, MD, President and CEO of the Kennedy Krieger Institute. “This study and other research from Kennedy Krieger’s Motion Analysis Laboratory provide a glimpse into the rehabilitative potential made possible through the pairing of our talented researchers and cutting-edge technologies.”

Past studies by Bastian and her colleagues have found that certain types of brain damage interfere with walking ability, while others do not. For example, individuals with damage to the cerebral hemispheres can adapt while those with damage to the cerebellum are rarely able to.

This body of work sheds light on the specificity of walking adaptations and demonstrates that patients with certain types of brain damage can store a new walking pattern in the short term. Based on these findings, Bastian’s goal is to learn how to make that pattern last for an extended period. Currently, Bastian is planning a study of stroke victims in order to test the long-term benefits of split-belt treadmill therapy.

She is also studying children with more extreme forms of brain damage, including those that undergo a hemispherectomy, a neurosurgical procedure to treat seizures in which an entire half of the brain is removed. The initial findings are quite promising, showing that these children can adapt in the short term and improve their walking patterns. These and other similar studies are leading researchers down the path to more targeted, rational therapies for patients with brain injuries.

This research is published in the August issue of Nature Neuroscience.


Story Source:

The above story is based on materials provided by Kennedy Krieger Institute. Note: Materials may be edited for content and length.


Cite This Page:

Kennedy Krieger Institute. "Independent Brain Networks Control Human Walking." ScienceDaily. ScienceDaily, 14 August 2007. <www.sciencedaily.com/releases/2007/08/070807135759.htm>.
Kennedy Krieger Institute. (2007, August 14). Independent Brain Networks Control Human Walking. ScienceDaily. Retrieved November 23, 2014 from www.sciencedaily.com/releases/2007/08/070807135759.htm
Kennedy Krieger Institute. "Independent Brain Networks Control Human Walking." ScienceDaily. www.sciencedaily.com/releases/2007/08/070807135759.htm (accessed November 23, 2014).

Share This


More From ScienceDaily



More Mind & Brain News

Sunday, November 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Could Your Genes Be The Reason You're Single?

Could Your Genes Be The Reason You're Single?

Newsy (Nov. 21, 2014) Researchers in Beijing discovered a gene called 5-HTA1, and carriers are reportedly 20 percent more likely to be single. Video provided by Newsy
Powered by NewsLook.com
Milestone Birthdays Can Bring Existential Crisis, Study Says

Milestone Birthdays Can Bring Existential Crisis, Study Says

Newsy (Nov. 21, 2014) Researchers find that as people approach new decades in their lives they make bigger life decisions. Video provided by Newsy
Powered by NewsLook.com
You Don't Have To Be Alcohol Dependent To Need Treatment

You Don't Have To Be Alcohol Dependent To Need Treatment

Newsy (Nov. 21, 2014) A study by the Centers for Disease Control and Prevention found 9 out of 10 excessive drinkers in the country are not alcohol dependent. Video provided by Newsy
Powered by NewsLook.com
Your Complicated Job Might Keep Your Brain Young

Your Complicated Job Might Keep Your Brain Young

Newsy (Nov. 20, 2014) Researchers at the University of Edinburgh found the more complex your job is, the sharper your cognitive skills will likely be as you age. 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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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