Featured Research

from universities, journals, and other organizations

Researchers Develop Neural Prosthesis Allowing A Monkey To Feed Self Using Only Its Brain

Date:
October 28, 2004
Source:
University Of Pittsburgh Medical Center
Summary:
Researchers at the University of Pittsburgh have demonstrated that a monkey can feed itself with a robotic arm simply by using signals from its brain, an advance that could enhance prosthetics for people, especially those with spinal cord injuries.

SAN DIEGO, Oct. 26 – Researchers at the University of Pittsburgh have demonstrated that a monkey can feed itself with a robotic arm simply by using signals from its brain, an advance that could enhance prosthetics for people, especially those with spinal cord injuries.

The robotic arm, or neural prosthesis, is about the size of a child's arm and moves much like a natural arm, with a fully mobile shoulder and elbow and a simple gripper that allows the monkey to grasp and hold food while its own arms are restrained.

The arm is wired into the monkey's brain and intercepts signals through electrodes attached to tiny probes that tap into neuronal pathways in the motor cortex, a region of the brain responsible for voluntary movement. The neurons' collective activity is fed through an algorithm developed at the University of Pittsburgh and then sent to the arm to tell it what direction to go.

"This is a breakthrough in the development of neural prosthetic devices that will someday lead to devices that could help people who are paralyzed or who have lost limbs," said Andrew Schwartz, Ph.D., professor of neurobiology at the University of Pittsburgh School of Medicine and senior researcher on the project.

The research was detailed in a press conference today at the 2004 Annual Meeting of the Society for Neuroscience in San Diego.

According to Dr. Schwartz, a part of the brain that controls movement, called the primary motor cortex, contains neurons that fire like a Geiger counter in different directions. The direction to which a neuron fires fastest is called its "preferred direction." Many motor cortical cells change their firing rate for each movement, and this activity from the many neurons is routed through the spinal cord to different muscle groups to generate movement.

It takes thousands of neurons firing in concert to allow even the most simple of movements, and it would be impossible to tap into all of them, so the Pitt team developed an algorithm to fill in the missing neuron signals, allowing them to get a useable signal from a manageable number of electrodes. The algorithm they developed to decode the cortical signals acts like a voting machine by using each cell's preferred direction as a label and taking a continuous tally of the population throughout the intended movement.

Monkeys were trained to reach for targets, and once the electrodes were in place, the algorithm was adjusted while the arms were restrained to assume the animal was intending to reach for targets.

"Each cell is movement-sensitive and has a preferred direction, and each cell's preferred direction is like a vote," said Chance Spalding, a bioengineering graduate student in Dr. Schwartz's lab who presented the findings. "When all of the votes are added up it gives us the population vector." These population vectors accurately predict the velocity of normal arm movement, and in the case of this prosthetic, serve as the control signal to convey the monkey's intention to the prosthetic arm.

Because the software had to rely on a small number of the thousands of neurons needed to move the arm, the monkey did the rest of the work, learning through biofeedback how to refine the arm's movements by modifying the firing rates of the recorded neurons.

For the task, food was placed at different locations in front of the monkey, and the animal, with its own arms restrained, used the robotic arm to bring the food to its mouth.

"The next step with this device is to add realistic hand and finger movement," said Meel Velliste, Ph.D., a postdoctoral fellow in the Schwartz lab. "This presents quite a challenge because there are hundreds of different subtle movements we make with our hands and we will need to interpret all of them."

The arm was developed by the Pitt researchers and custom-built by Keshen Prosthetics in Shanghai, China. The software that controls the arm was developed at Pitt and Arizona State University. Modifications to the original arm were made at the Robotics Institute at Carnegie Mellon University.

In addition to Drs. Schwartz and Velliste and Mr. Spalding, other authors include Beada Jarosiewicz, Ph.D., and Gordon Kirkwood, both of the University of Pittsburgh.


Story Source:

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


Cite This Page:

University Of Pittsburgh Medical Center. "Researchers Develop Neural Prosthesis Allowing A Monkey To Feed Self Using Only Its Brain." ScienceDaily. ScienceDaily, 28 October 2004. <www.sciencedaily.com/releases/2004/10/041027143313.htm>.
University Of Pittsburgh Medical Center. (2004, October 28). Researchers Develop Neural Prosthesis Allowing A Monkey To Feed Self Using Only Its Brain. ScienceDaily. Retrieved October 2, 2014 from www.sciencedaily.com/releases/2004/10/041027143313.htm
University Of Pittsburgh Medical Center. "Researchers Develop Neural Prosthesis Allowing A Monkey To Feed Self Using Only Its Brain." ScienceDaily. www.sciencedaily.com/releases/2004/10/041027143313.htm (accessed October 2, 2014).

Share This



More Mind & Brain News

Thursday, October 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Pregnancy Spacing Could Have Big Impact On Autism Risks

Pregnancy Spacing Could Have Big Impact On Autism Risks

Newsy (Oct. 1, 2014) A new study says children born less than one year and more than five years after a sibling can have an increased risk for autism. Video provided by Newsy
Powered by NewsLook.com
Stopping School Violence

Stopping School Violence

Ivanhoe (Oct. 1, 2014) A trauma doctor steps out of the hospital and into the classroom to teach kids how to calmly solve conflicts, avoiding a trip to the ER. Video provided by Ivanhoe
Powered by NewsLook.com
Pineal Cysts: Debilitating Pain

Pineal Cysts: Debilitating Pain

Ivanhoe (Oct. 1, 2014) A tiny cyst in the brain that can cause debilitating symptoms like chronic headaches and insomnia, and the doctor who performs the delicate surgery to remove them. Video provided by Ivanhoe
Powered by NewsLook.com
Burning Away Brain Tumors

Burning Away Brain Tumors

Ivanhoe (Oct. 1, 2014) Doctors are 'cooking' brain tumors. Hear how this new laser-heat procedure cuts down on recovery time. Video provided by Ivanhoe
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