Featured Research

from universities, journals, and other organizations

It's Not All In The Wrist

Date:
December 7, 2004
Source:
University Of Southern California
Summary:
Drum the tip of a finger on a typewriter key quickly “eeeeee.” Now, stop and type “e.” Take a moment, type “e” again. Take another moment, repeat. The motion in all cases is exactly the same, performed by the same finger. But according to a study done by a USC neural specialist and colleagues, the brain processes that make them happen are completely different.

Drum the tip of a finger on a typewriter key quickly “eeeeee.” Now, stop and type “e.” Take a moment, type “e” again. Take another moment, repeat. The motion in all cases is exactly the same, performed by the same finger.

Related Articles


But according to a study done by a USC neural specialist and colleagues, the brain processes that make them happen are completely different.

The insight may lead to better movement control by humanoid robots, new methods of movement rehabilitation for people and an understanding of the effect of music.

Stefan Schaal, associate professor of computer science in the USC Viterbi School of Engineering, led the international team that used functional Magnetic Resonance Imaging (fMRI) scans to test a longstanding question regarding “rhythmic” versus “discrete” movement.

“Rhythmic movements such as walking, chewing or scratching are found in many organisms, ranging from insects to primates,” said Schaal in a recent article published in Nature Neuroscience. “In contrast, discrete movements like reaching and kicking are behaviors that have reached sophistication in young species, particularly in primates.”

Schaal is a robotics expert with an extensive background in neuroscience who draws inspiration for robot controls from biological models. Researchers have historically treated the two different kinds of movement as fundamentally the same in terms of control, he said, considering one as being a special form of the other.

Thus specialists studying discrete movement have considered rhythm a subset of discrete movement – the same thing speeded up and repeated.

But behaviorists studying rhythmic movement such as walking have considered discrete movement as the same thing slowed and aborted after only a single act of rhythmic movement.

In a carefully arranged set of experiments, Schaal and coworkers from Pennsylvania State and ATR Computational Neuroscience Laboratories in Kyoto, Japan, showed that control mechanisms for the two types of movement are drastically distinct.

The study monitored 11 volunteer subjects, who performed a simple flex of the wrist while undergoing fMRI monitoring.

A visual signal instructed the subjects to do one of three actions: rhythm – flexing the wrist repeatedly at a comfortable pace, back and forth; discrete – flexing the wrist, pausing, flexing it back, and rest. Another set of experiments had the timing of the rhythm dictated to the subjects by a metronome.

The resulting fMRI records displayed far-reaching differences. Rhythmic motion created activity only in the motor areas of the opposite brain hemisphere and the cerebellum.

Discrete activity was much more extensive, including numerous areas on both sides of the brain and “planning areas” not directly connected with motor execution.

The difference held up even when careful controls made sure that the amount of actual activity – the number of up-and-down flexes and their velocity – was the same.

“We believe these results provide strong evidence to refute the hypothesis that rhythmic movement is generated with the help of the discrete movement system,” the authors wrote.

However, the opposite is not the case: the authors found that “discrete movement could indeed be generated with the help of the rhythmic movement system.”

“What our results indicate is that we really deal with two very separate systems in movement,” Schaal said. “There is an automatic system that, literally, functions without any thought; and a separate cognitive system that orchestrates more complex movement.

And music?

“Computational neuroscientists theorize that rhythmic movements are generated from oscillator circuits in the brain, and it may be that these inherently rhythmic neural systems make it to easy for us to swing to the rhythmic of music,” the scientist said.

Meanwhile, Schaal and his colleagues are working on converting their results to humanoid robot algorithms that capture such behavior and could give future robots a bit more “rhythm” in their stride.

“But don’t look for them right away in hip-hop videos,” Schaal said.

Dagmar Sternad of the Penn State department of Kinesiology and Rieko Osu and Mitsuo Kawato of ATR-Kyoto were coauthors of the study, which was funded by the National Science Foundation, Japanese Science and Technology Agency, and ATR.


Story Source:

The above story is based on materials provided by University Of Southern California. Note: Materials may be edited for content and length.


Cite This Page:

University Of Southern California. "It's Not All In The Wrist." ScienceDaily. ScienceDaily, 7 December 2004. <www.sciencedaily.com/releases/2004/12/041206210847.htm>.
University Of Southern California. (2004, December 7). It's Not All In The Wrist. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2004/12/041206210847.htm
University Of Southern California. "It's Not All In The Wrist." ScienceDaily. www.sciencedaily.com/releases/2004/12/041206210847.htm (accessed October 25, 2014).

Share This



More Mind & Brain News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Academic Scandal Shocks UNC

Academic Scandal Shocks UNC

AP (Oct. 23, 2014) A scandal involving bogus classes and inflated grades at the University of North Carolina was bigger than previously reported, a new investigation found. (Oct. 23) Video provided by AP
Powered by NewsLook.com
Working Mother Getaway: Beaches Turks & Caicos

Working Mother Getaway: Beaches Turks & Caicos

Working Mother (Oct. 22, 2014) Feast your eyes on this gorgeous family-friendly resort. Video provided by Working Mother
Powered by NewsLook.com
What Your Favorite Color Says About You

What Your Favorite Color Says About You

Buzz60 (Oct. 22, 2014) We all have one color we love to wear, and believe it or not, your color preference may reveal some of your character traits. In celebration of National Color Day, Krystin Goodwin (@kyrstingoodwin) highlights what your favorite colors may say about you. Video provided by Buzz60
Powered by NewsLook.com
First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

Newsy (Oct. 21, 2014) A medical team has for the first time given a man the ability to walk again after transplanting cells from his brain onto his severed spinal cord. 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