Featured Research

from universities, journals, and other organizations

How neurons control fine motor behavior of the arm

Date:
January 31, 2014
Source:
University of Basel
Summary:
Motor commands issued by the brain to activate arm muscles take two different routes. As a research group has now discovered, many neurons in the spinal cord send their instructions not only towards the musculature, but at the same time also back to the brain via an exquisitely organized network.

Motor commands issued by the brain to activate arm muscles take two different routes. As the research group led by Professor Silvia Arber at the University of Basel's Biozentrum and the Friedrich Miescher Institute for Biomedical Research has now discovered, many neurons in the spinal cord send their instructions not only towards the musculature, but at the same time also back to the brain via an exquisitely organized network. This dual information stream provides the neural basis for accurate control of arm and hand movements. These findings have now been published in Cell.

Movement is a fundamental capability of humans and animals, involving the highly complex interplay of brain, nerves and muscles. Movements of our arms and hands, in particular, call for extremely precise coordination. The brain sends a constant stream of commands via the spinal cord to our muscles to execute a wide variety of movements. This stream of information from the brain reaches interneurons in the spinal cord, which then transmit the commands via further circuits to motor neurons innervating muscles. The research group led by Silvia Arber at the Biozentrum of the University of Basel and the Friedrich Miescher Institute for Biomedical Research has now elucidated the organization of a second information pathway taken by these commands.

Cc to the brain: one command -- two directions

The scientists showed that many interneurons in the mouse spinal cord not only transmit their signals via motor neurons to the target muscle, but also simultaneously send a copy of this information back to the brain. Chiara Pivetta, first author of the publication, explains: "The motor command to the muscle is sent in two different directions -- in one direction, to trigger the desired muscular contraction and in the other, to inform the brain that the command has actually been passed on to the musculature." In analogy to e mail transmission, the information is thus not only sent to the recipient but also to the original requester.

Information to brainstem nucleus segregated by function

What happens to the information sent by spinal interneurons to the brain? As Arber's group discovered, this input is segregated by function and spatially organized within a brainstem nucleus. Information from different types of interneurons thus flows to different areas of the nucleus. For example, spinal information that will influence left-right coordination of a movement is collected at a different site than information affecting the speed of a movement.

Fine motor skills supported by dual information stream

Arber comments: "From one millisecond to the next, this extremely precise feedback ensures that commands are correctly transmitted and that -- via the signals sent back to the brain from the spinal cord -- the resulting movement is immediately coordinated with the brain and adjusted." Interestingly, the scientists only observed this kind of information flow to the brain for arm, but not for leg control. "What this shows," says Arber, "is that this information pathway is most likely important for fine motor skills. Compared to the leg, movements of our arm and especially our hands have to be far more precise. Evidently, our body can only ensure this level of accuracy in motor control with constant feedback of information."

In further studies, Silvia Arber's group now plans to investigate what happens if the flow of information back to the brain is disrupted in specific ways. Since some interneurons facilitate and others inhibit movement, such studies could provide additional insights into the functionality of circuits controlling movement.


Story Source:

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


Journal Reference:

  1. Chiara Pivetta, Maria Soledad Esposito, Markus Sigrist, and Silvia Arber. Motor-Circuit Communication Matrix from Spinal Cord to Brainstem Neurons Revealed by Developmental Origin. Cell, Volume 156, Issue 3, 537-548, 30 January 2014

Cite This Page:

University of Basel. "How neurons control fine motor behavior of the arm." ScienceDaily. ScienceDaily, 31 January 2014. <www.sciencedaily.com/releases/2014/01/140131101201.htm>.
University of Basel. (2014, January 31). How neurons control fine motor behavior of the arm. ScienceDaily. Retrieved August 22, 2014 from www.sciencedaily.com/releases/2014/01/140131101201.htm
University of Basel. "How neurons control fine motor behavior of the arm." ScienceDaily. www.sciencedaily.com/releases/2014/01/140131101201.htm (accessed August 22, 2014).

Share This




More Mind & Brain News

Friday, August 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Lost Brain Cells To Blame For Sleep Problems Among Seniors

Lost Brain Cells To Blame For Sleep Problems Among Seniors

Newsy (Aug. 21, 2014) According to a new study, elderly people might have trouble sleeping because of the loss of a certain group of neurons in the brain. Video provided by Newsy
Powered by NewsLook.com
Do More Wedding Guests Make A Happier Marriage?

Do More Wedding Guests Make A Happier Marriage?

Newsy (Aug. 20, 2014) A new study found couples who had at least 150 guests at their weddings were more likely to report being happy in their marriages. Video provided by Newsy
Powered by NewsLook.com
Charter Schools Alter Post-Katrina Landscape

Charter Schools Alter Post-Katrina Landscape

AP (Aug. 20, 2014) Nine years after Hurricane Katrina, charter schools are the new reality of public education in New Orleans. The state of Louisiana took over most of the city's public schools after the killer storm in 2005. (Aug. 20) Video provided by AP
Powered by NewsLook.com
Researcher Testing on-Field Concussion Scanners

Researcher Testing on-Field Concussion Scanners

AP (Aug. 19, 2014) Four Texas high school football programs are trying out an experimental system designed to diagnose concussions on the field. The technology is in response to growing concern over head trauma in America's most watched sport. (Aug. 19) Video provided by AP
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