Navigation Links
Time-keeping brain neurons discovered
Date:10/22/2009

Groups of neurons that precisely keep time have been discovered in the primate brain by a team of researchers that includes Dezhe Jin, assistant professor of physics at Penn State University and two neuroscientists from the RIKEN Brain Science Institute in Japan and the Massachusetts Institute of Technology (MIT). "This research is the first time that precise time-keeping activities have been identified in recordings of neuron activity," Jin said. The time-keeping neurons are in two interconnected brain regions, the prefrontal cortex and the striatum, both of which are known to play critical roles in learning, movement, and thought control.

The timing of individual actions, like speaking, driving a car, or throwing a football, requires very precise control. Although the lives of humans and other primates are extremely dependent on this remarkable capability, surprisingly little has been known about how brain cells keep track of time. This new discovery, published this week in the Proceedings of the National Academy of Sciences, is an important step toward answering this fundamental question.

To make the discovery, Jin analyzed thousands of neural-activity recordings made by Naotaka Fujii, from RIKEN, who then was a postdoctoral researcher in the lab of Ann Graybiels, an institute professor at MIT. Jin developed the computational tools that enabled the discovery of the novel results to emerge from the team's vast data set.

"The key finding is that neurons in the prefrontal cortex and the striatum encode the time information associated with sensory cues," Jin explained. "Visual cues, for example, elicit a variety of responses in a particular population of neurons. We found that the brain is able to tell the passage of time from the visual cues because different neurons are active at different times. Most remarkably we found that there are neurons that are active at precise times after a particular visual cue, and these neurons act like clocks that mark time."

The team of researchers trained two macaque monkeys to perform a simple eye-movement task. After receiving a "go" signal, the monkeys were free to perform the task at their own speed. The researchers found that neurons in the prefrontal cortex and the striatum consistently fired at specific times after the "go" signal -- at 100 milliseconds, 110 milliseconds, 150 milliseconds, and other intervals. Like a stopwatch, these neurons provided a fine-scale coverage over a period of several seconds. The combined activity of these neurons provided "time stamps" that could specify any given time point with a remarkable precision of less than 50 milliseconds, which is more than sufficient to account for most behaviors.

"Another key finding of our work is that the brains of the monkeys constructed neural activities to encode time even though timing was not required for the experimental task," Jin said. "We suggest that time encoding is the essential function of the brain's neural networks."

Jin said this kind of time-keeping activity long had been suggested in theories of how animals learn to recognize a stimulus that leads to delayed rewards, but his team's work is the first experimental demonstration of this Time-keeping function using recordings of neuron activity.

The discovery opens the door to many investigations, including how the brain produces this time code, and how the time code is used to control behavior and learning. In the longer term, the ability to read the brain's natural time code may facilitate the development of neural prosthetic devices for conditions such as Parkinson's disease, in which neurons in the prefrontal cortex and basal ganglia are disrupted and the ability to control the timing of movements is impaired.


'/>"/>

Contact: Barbara K. Kennedy
science@psu.edu
814-863-4682
Penn State
Source:Eurekalert

Related biology news :

1. Invasion of the brain tumors
2. HIV is a double hit to the brain
3. AIDS interferes with stem cells in the brain
4. 60 second test could help early diagnosis of common brain diseases
5. U of MN researchers discover noninvasive diagnostic tool for brain diseases
6. U of Minnesota researchers discover noninvasive diagnostic tool for brain diseases
7. Influence of sex and handedness on brain is similar in capuchin monkeys and humans
8. Inside the brain of a crayfish
9. Specific brain protein required for nerve cell connections to form and function
10. Brains timing linked with timescales of the natural visual world
11. Adult brain can change, study confirms
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/5/2017)... 5, 2017 Today HYPR Corp. , ... server component of the HYPR platform is officially ... end-to-end security architecture that empowers biometric authentication across Fortune ... already secured over 15 million users across the financial ... connected home product suites and physical access represent a ...
(Date:3/30/2017)... -- On April 6-7, 2017, Sequencing.com will host the world,s ... at Microsoft,s headquarters in Redmond, Washington ... health and wellness apps that provide a unique, personalized ... is the first hackathon for personal genomics and the ... the genomics, tech and health industries are sending teams ...
(Date:3/28/2017)... , March 28, 2017 ... Biometrics), Hardware (Camera, Monitors, Servers, Storage Devices), Software (Video ... and Region - Global Forecast to 2022", published by ... in 2016 and is projected to reach USD 75.64 ... 2017 and 2022. The base year considered for the ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... , ... October 11, 2017 , ... ... gene in its endogenous context, enabling overexpression experiments and avoiding the use of ... small RNA guides is transformative for performing systematic gain-of-function studies. , This ...
(Date:10/11/2017)... -- VMS BioMarketing, a leading provider of patient support solutions, has ... (CNE) network, which will launch this week. The VMS CNEs ... professionals to enhance the patient care experience by delivering peer-to-peer ... care professionals to help women who have been diagnosed and ... ...
(Date:10/11/2017)... ... October 11, 2017 , ... ... has granted orphan drug designation to SBT-100, its novel anti-STAT3 (Signal Transducer and ... of osteosarcoma. SBT-100 is able to cross the cell membrane and bind intracellular ...
(Date:10/10/2017)... ... October 10, 2017 , ... Dr. Bob Harman, founder and ... San Diego Rotary Club. The event entitled “Stem Cells and Their ... 300+ attendees. Dr. Harman, DVM, MPVM was joined by two human doctors: Peter ...
Breaking Biology Technology: