Navigation Links
Researchers discover workings of brain's 'GPS system'
Date:3/7/2013

Just as a global positioning system (GPS) helps find your location, the brain has an internal system for helping determine the body's location as it moves through its surroundings.

A new study from researchers at Princeton University provides evidence for how the brain performs this feat. The study, published in the journal Nature, indicates that certain position-tracking neurons called grid cells ramp their activity up and down by working together in a collective way to determine location, rather than each cell acting on its own as was proposed by a competing theory.

Grid cells are neurons that become electrically active, or "fire," as animals travel in an environment. First discovered in the mid-2000s, each cell fires when the body moves to specific locations, for example in a room. Amazingly, these locations are arranged in a hexagonal pattern like spaces on a Chinese checker board.

"Together, the grid cells form a representation of space," said David Tank, Princeton's Henry L. Hillman Professor in Molecular Biology and leader of the study. "Our research focused on the mechanisms at work in the neural system that forms these hexagonal patterns," he said. The first author on the paper was graduate student Cristina Domnisoru, who conducted the experiments together with postdoctoral researcher Amina Kinkhabwala.

Domnisoru measured the electrical signals inside individual grid cells in mouse brains while the animals traversed a computer-generated virtual environment, developed previously in the Tank lab. The animals moved on a mouse-sized treadmill while watching a video screen in a set-up that is similar to video-game virtual reality systems used by humans.

She found that the cell's electrical activity, measured as the difference in voltage between the inside and outside of the cell, started low and then ramped up, growing larger as the mouse reached each point on the hexagonal grid and then falling off as the mouse moved away from that point.

This ramping pattern corresponded with a proposed mechanism of neural computation called an attractor network. The brain is made up of vast numbers of neurons connected together into networks, and the attractor network is a theoretical model of how patterns of connected neurons can give rise to brain activity by collectively working together. The attractor network theory was first proposed 30 years ago by John Hopfield, Princeton's Howard A. Prior Professor in the Life Sciences, Emeritus.

The team found that their measurements of grid cell activity corresponded with the attractor network model but not a competing theory, the oscillatory interference model. This competing theory proposed that grid cells use rhythmic activity patterns, or oscillations, which can be thought of as many fast clocks ticking in synchrony, to calculate where animals are located. Although the Princeton researchers detected rhythmic activity inside most neurons, the activity patterns did not appear to participate in position calculations.


'/>"/>

Contact: Catherine Zandonella
czandone@princeton.edu
Princeton University
Source:Eurekalert  

Related biology news :

1. Study by UC Santa Barbara researchers suggests that bacteria communicate by touch
2. UC Santa Barbara researchers discover genetic link between visual pathways of hydras and humans
3. Researchers attempt to solve problems of antibiotic resistance and bee deaths in one
4. UNH researchers find African farmers need better climate change data to improve farming practices
5. Ottawa researchers to lead world-first clinical trial of stem cell therapy for septic shock
6. Researchers uncover molecular pathway through which common yeast becomes fungal pathogen
7. Researchers print live cells with a standard inkjet printer
8. Columbia Engineering and Penn researchers increase speed of single-molecule measurements
9. Researchers reveal how a single gene mutation leads to uncontrolled obesity
10. Researchers discover novel therapy for Crohns disease
11. New paper by Notre Dame researchers describes method for cleaning up nuclear waste
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Researchers discover workings of brain's 'GPS system'
(Date:3/24/2017)... Research and Markets has announced the addition of the ... Forecast to 2025" report to their offering. ... The Global Biometric Vehicle Access System ... over the next decade to reach approximately $1,580 million by 2025. ... forecasts for all the given segments on global as well as ...
(Date:3/22/2017)... 21, 2017 Vigilant Solutions , a ... enforcement agencies, announced today the appointment of retired FBI ... public safety business development. Mr. Sheridan brings ... including a focus on the aviation transportation sector, to ... position, Mr. Sheridan served as the Aviation Liaison Agent ...
(Date:3/9/2017)... , March 9, 2017 4Dx has ... World Lung Imaging Workshop at the University of Pennsylvania. ... invited to deliver the latest data to world leaders ... event brings together leaders at the forefront of the ... lung imaging. "The quality of the ...
Breaking Biology News(10 mins):
(Date:4/20/2017)... ... April 20, 2017 , ... Husson University will be celebrating ... body of knowledge during its Eighth Annual Research and Scholarship Day ... Atrium. During the event, undergraduates, graduate students, and faculty members from all of ...
(Date:4/20/2017)... ... April 20, 2017 , ... ... advanced technology applications, announced today that Chief Executive Officer (CEO) Debbie Gustafson has ... is the global industry association connecting the electronics manufacturing supply chain. The ...
(Date:4/20/2017)... Dutch philosopher Koert van Mensvoort - founder of the Next Nature ... Eindhoven - has written a ,Letter to Humanity, in support of ... becoming a slave and victim to its own technology, but to employ technology ... ... Mensvoort – founder of the Next Nature Network and Fellow of ‘Next Nature’ ...
(Date:4/19/2017)... ... 2017 , ... The Vibrating Orifice Aerosol Generator (VOAG) was ... droplets of known diameters for research applications such as for calibrating droplet measuring ... monodisperse droplets. , The VOAG requires forcing liquid out of an orifice ...
Breaking Biology Technology: