Featured Research

from universities, journals, and other organizations

GPS in the head? Rhythmic activity of neurons to code position in space

Date:
September 15, 2011
Source:
Ruhr-Universitaet-Bochum
Summary:
Researchers investigated how the rhythmic activity of nerve cells supports spatial navigation. The scientists showed that cells in the entorhinal cortex, which is important for spatial navigation, oscillate with individual frequencies. These frequencies depend on the position of the cells within the entorhinal cortex.

Cell in the entorhinal cortex.
Credit: Image courtesy of Ruhr-Universitaet-Bochum

Prof. Dr. Motoharu Yoshida and colleagues from Boston University investigated how the rhythmic activity of nerve cells supports spatial navigation. The research scientists showed that cells in the entorhinal cortex, which is important for spatial navigation, oscillate with individual frequencies. These frequencies depend on the position of the cells within the entorhinal cortex.

Related Articles


"Up to now people believed that the frequency is modulated by the interaction with neurons in other brain regions," says Yoshida. "However, our data indicate that this may not be the case. The frequency could be fixed for each cell. We may need new models to describe the contribution of rhythmic activity to spatial navigation."

The researchers report in the Journal of Neuroscience.

Rhythmic brains find their way

"The brain seems to represent the environment like a map with perfect distances and angles," explains Yoshida. "However, we are not robots with GPS systems in our head. But the rhythmic activity of the neurons in the entorhinal cortex seems to create a kind of map."

The activity of individual neurons in this brain region represents different positions in space. If an animal is in a certain location, a certain neuron fires. The rhythmic activity of each cell may enable us to code a set of positions, which form a regular grid. Computer simulations of previous studies suggested that signals from cells in other brain regions influence the rhythmic activity of the entorhinal neurons. Using electrophysiological recordings in rats and computer simulations, Yoshida and his colleagues examined the nature of this influence.

Expressing the cellular rhythm in numbers

In order to simulate the input signals from other cells, Yoshida and his colleagues varied the voltage at the cell membrane (membrane potential). A change of the membrane potential from the resting state to more positive values thereby resembled an input signal from another cell. The membrane potential of the cells in the entorhinal cortex is not constant, but increases and decreases periodically; it oscillates. The scientists determined how fast the membrane potential changed (frequency) and how large the differences in these changes were (amplitude), when they shifted the mean membrane potential around which the potential oscillated.

Position determines the frequency

In the resting state, the membrane potential oscillations of the entorhinal cells were weak and in a broad frequency range. If the membrane potential was shifted to more positive values, thus mimicking the input of another cell, the oscillations became stronger. Additionally, the membrane potential now fluctuated with a distinct frequency, which was dependent on the position of the cell within the entorhinal cortex. Cells in the upper portion of this brain region showed oscillations with higher frequency than cells in the lower portion. However, the frequency was independent of further changes in membrane potential and thus largely independent of input signals from other cells.


Story Source:

The above story is based on materials provided by Ruhr-Universitaet-Bochum. Note: Materials may be edited for content and length.


Journal Reference:

  1. M. Yoshida, L. M. Giocomo, I. Boardman, M. E. Hasselmo. Frequency of Subthreshold Oscillations at Different Membrane Potential Voltages in Neurons at Different Anatomical Positions on the Dorsoventral Axis in the Rat Medial Entorhinal Cortex. Journal of Neuroscience, 2011; 31 (35): 12683 DOI: 10.1523/JNEUROSCI.1654-11.2011

Cite This Page:

Ruhr-Universitaet-Bochum. "GPS in the head? Rhythmic activity of neurons to code position in space." ScienceDaily. ScienceDaily, 15 September 2011. <www.sciencedaily.com/releases/2011/09/110915102210.htm>.
Ruhr-Universitaet-Bochum. (2011, September 15). GPS in the head? Rhythmic activity of neurons to code position in space. ScienceDaily. Retrieved December 18, 2014 from www.sciencedaily.com/releases/2011/09/110915102210.htm
Ruhr-Universitaet-Bochum. "GPS in the head? Rhythmic activity of neurons to code position in space." ScienceDaily. www.sciencedaily.com/releases/2011/09/110915102210.htm (accessed December 18, 2014).

Share This


More From ScienceDaily



More Mind & Brain News

Thursday, December 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Yoga Could Be As Beneficial For The Heart As Walking, Biking

Yoga Could Be As Beneficial For The Heart As Walking, Biking

Newsy (Dec. 17, 2014) Yoga can help your weight, blood pressure, cholesterol and heart just as much as biking and walking does, a new study suggests. Video provided by Newsy
Powered by NewsLook.com
1st Responders Trained for Autism Sensitivity

1st Responders Trained for Autism Sensitivity

AP (Dec. 16, 2014) More departments are ordering their first responders to sit in on training sessions that focus on how to more effectively interact with those with autism spectrum disorder (Dec. 16) Video provided by AP
Powered by NewsLook.com
Guys Are Idiots, According To Sarcastic Study

Guys Are Idiots, According To Sarcastic Study

Newsy (Dec. 12, 2014) A study out of Britain suggest men are more idiotic than women based on the rate of accidental deaths and other factors. Video provided by Newsy
Powered by NewsLook.com
Believing in Father Christmas Good for Children's Imaginations

Believing in Father Christmas Good for Children's Imaginations

AFP (Dec. 12, 2014) As the countdown to Christmas gets underway, so too does the Father Christmas conspiracy. But psychologists say that telling our children about Santa, flying reindeer and elves is good for their imaginations. Duration: 01:57 Video provided by AFP
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