Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sharply focused on neurons, light controls a worm's behavior

19.01.2011
Scientists commandeer a freely moving organism's nervous system without wires or electrodes

Physicists and bioengineers have developed an optical instrument allowing them to control the behavior of a worm just by shining a tightly focused beam of light at individual neurons inside the organism.

The pioneering optogenetic research, by a team at Harvard University, the University of Pennsylvania, and the University of Massachusetts Medical School, is described this week in the journal Nature Methods. Their device is known as the CoLBeRT (Controlling Locomotion and Behavior in Real Time) system for optical control of freely moving animals, in this case the millimeter-long worm Caenorhabditis elegans.

"This optical instrument allows us to commandeer the nervous system of swimming or crawling nematodes using pulses of blue and green light -- no wires, no electrodes," says Aravinthan D.T. Samuel, a professor of physics and affiliate of Harvard's Center for Brain Science. "We can activate or inactivate individual neurons or muscle cells, essentially turning the worm into a virtual biorobot."

Samuel and colleagues chose to work with C. elegans, an organism often used in biological research, because of its optical transparency, its well-defined nervous system of exactly 302 neurons, and its ease of manipulation. They genetically modified the worms so their neurons express the light-activated proteins channelrhodopsin-2 and halorhodopsin.

In conjunction with high-precision micromirrors that can direct laser light to individual cells, the scientists were then able to stimulate -- using blue light -- or inhibit -- using green light -- behaviors such as locomotion and egg-laying.

"If you shine blue light at a particular neuron near the front end of the worm, it perceives that as being touched and will back away," says co-author Andrew M. Leifer, a Ph.D. student in Harvard's Department of Physics and Center for Brain Science. "Similarly, blue light shined at the tail end of the modified worm will prompt it to move forward."

The scientists were also able to use pulses of light to steer the worms left or right. By stimulating neurons associated with the worm's reproductive system, they were even able to rouse the animal into secreting an egg.

Key to the CoLBeRT system is a tracking microscope recording the motion of a swimming or crawling worm, paired with image processing software that can quickly estimate the location of individual neurons and instruct a digital micromirror device to illuminate targeted cells. Because cells in an unrestrained worm represent a rapidly moving target, the system can capture 50 frames per second and attain spatial resolution of just 30 microns.

"This development should have profound consequences in systems neuroscience as a new tool to probe nervous system activity and behavior, as well as in bioengineering and biorobotics," Samuel says. "Our laboratory has been pioneering new optical methods to study the nervous system, and this is the latest, and perhaps our greatest, invention."

Leifer and Samuel's co-authors on the Nature Methods paper are Christopher Fang-Yen of the University of Pennsylvania, Marc Gershow of Harvard, and Mark J. Alkema of the University of Massachusetts Medical School. Their work was supported by the Dana Foundation, the National Science Foundation, and the National Institutes of Health.

Steve Bradt | EurekAlert!
Further information:
http://www.harvard.edu

More articles from Physics and Astronomy:

nachricht Squeezing light at the nanoscale
17.06.2018 | Harvard John A. Paulson School of Engineering and Applied Sciences

nachricht The Fraunhofer IAF is a »Landmark in the Land of Ideas«
15.06.2018 | Fraunhofer-Institut für Angewandte Festkörperphysik IAF

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

Im Focus: Water is not the same as water

Water molecules exist in two different forms with almost identical physical properties. For the first time, researchers have succeeded in separating the two forms to show that they can exhibit different chemical reactivities. These results were reported by researchers from the University of Basel and their colleagues in Hamburg in the scientific journal Nature Communications.

From a chemical perspective, water is a molecule in which a single oxygen atom is linked to two hydrogen atoms. It is less well known that water exists in two...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

A sprinkle of platinum nanoparticles onto graphene makes brain probes more sensitive

15.06.2018 | Materials Sciences

100 % Organic Farming in Bhutan – a Realistic Target?

15.06.2018 | Ecology, The Environment and Conservation

Perovskite-silicon solar cell research collaboration hits 25.2% efficiency

15.06.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>