Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

How the grid cell system of the brain maps mental spaces

12.10.2018

How exactly the grid cell system works in the human brain, and in particular with which temporal dynamics, has until now been speculation. A much-discussed possibility is that the signals from these cells create maps of “cognitive spaces” in which humans mentally organize and store the complexities of their internal and external environments. A European–American team of scientists has now been able to demonstrate, with electrophysiological evidence, the existence of grid-like activity in the human brain.

It has long been known that so-called place cells in the human hippocampus are responsible for coding one’s position in space. A related type of brain cell, called grid cells, encodes a variety of positions that are evenly distributed across space. This results in a kind of honeycomb pattern tiling the space.


A related type of brain cell, called grid cells, encodes a variety of positions that are evenly distributed across space.

© iStock.com/matejmo


Prof. Christian Doeller, new director of MPI CBS

© TiTT Melhuus/ Kavli Institute for Systems Neuroscience

The cells exhibiting this pattern were discovered in the entorhinal cortex. How exactly the grid cell system works in the human brain, and in particular with which temporal dynamics, has until now been speculation. A much-discussed possibility is that the signals from these cells create maps of “cognitive spaces” in which humans mentally organize and store the complexities of their internal and external environments.

A European–American team of scientists has now been able to demonstrate, with electrophysiological evidence, the existence of grid-like activity in the human brain. Under the direction of Prof. Christian Doeller of the Max Planck Institute for Human Cognitive and Brain Sciences (MPI CBS) in Leipzig and Dr. Tobias Staudigl of the Donders Institute for Brain, Cognition and Behavior, Radboud University, The Netherlands, researchers used various methods to visualize grid cell activity while subjects explored images of everyday scenes.

"We assume that these spatial coding principles in the brain form the basis of higher cognitive performance—here in this study, in the field of perception, but possibly also in decision-making or even in social interaction," explained Prof. Doeller, who is now continuing his research as the new director of the MPI CBS in Leipzig.

To demonstrate the dynamics of the brain activity, the scientists performed independent measurements using two different methods. Thirty-six healthy participants were scanned using magnetoencephalography (MEG) and intracranial electroencephalography (EEG) was measured in an epileptic patient. During an MEG scan, subjects sit under a kind of helmet that measures magnetic fields caused by the electrical currents of active nerve cells.

"This enabled us to record data that is an expression of the momentary total activity of the brain, without any delay" explains Tobias Staudigl, first author of the study. He is currently conducting research at the Cedars-Sinai Medical Center in Los Angeles (USA). The participants viewed 200 pictures containing both indoor and outdoor scenes. "In addition to the MEG measurements, we also recorded their eye movements using an eye-tracker to determine how they visually explored the scenes of the images shown."

In the case of the epileptic patient, the researchers took advantage of the fact that for diagnostic purposes, prior to a brain surgery, he had been implanted with electrodes that could directly record electrical activity in the brain. He was asked to look at similar pictures with indoor and outdoor scenes, as well as with animals and faces. His eye movements were also measured, allowing the scientists to obtain an additional dataset to record the activation patterns of the cells.

"We looked at whether the activity patterns of the entire grid cell system have a specific structure, as has been assumed for a few years," reports Prof. Doeller. "By showing the subjects pictures of visual scenes, we were able to demonstrate that. This is the first time that this effect has been measured by MEG and EEG recordings, and it opens up many exciting opportunities for further research. For example, it could lead to new biomarkers for diseases such as Alzheimer's in the future. This is because in young adults with an increased risk of Alzheimer's disease, we have already seen that the activity of the grid cell system is reduced."

Wissenschaftliche Ansprechpartner:

Prof. Dr. Christian Doeller
Director MPI CBS
Telefon: +49 341 9940-2275
Fax: +49 341 9940-2204
E-Mail: doeller@cbs.mpg.de

Dr. Tobias Staudigl
Cedars-Sinai Medical Center, USA
E-Mail: tobias.stdgl@gmail.com

Originalpublikation:

Tobias Staudigl, Marcin Leszczynski, Joshua Jacobs, Sameer A. Sheth, Charles E. Schroeder, Ole Jensen, Christian F. Doeller (2018)
"Hexadirectional modulation of high-frequency electrophysiological activity in the human anterior medial temporal lobe maps visual space"
https://www.cell.com/current-biology/fulltext/S0960-9822(18)31260-0

Weitere Informationen:

http://www.cbs.mpg.de/970159/20181011-01

Bettina Hennebach | Max-Planck-Institut für Kognitions- und Neurowissenschaften

More articles from Life Sciences:

nachricht RUDN chemist tested a new nanocatalyst for obtaining hydrogen
18.10.2018 | RUDN University

nachricht Dandelion seeds reveal newly discovered form of natural flight
18.10.2018 | University of Edinburgh

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Goodbye, silicon? On the way to new electronic materials with metal-organic networks

Scientists at the Max Planck Institute for Polymer Research (MPI-P) in Mainz (Germany) together with scientists from Dresden, Leipzig, Sofia (Bulgaria) and Madrid (Spain) have now developed and characterized a novel, metal-organic material which displays electrical properties mimicking those of highly crystalline silicon. The material which can easily be fabricated at room temperature could serve as a replacement for expensive conventional inorganic materials used in optoelectronics.

Silicon, a so called semiconductor, is currently widely employed for the development of components such as solar cells, LEDs or computer chips. High purity...

Im Focus: Storage & Transport of highly volatile Gases made safer & cheaper by the use of “Kinetic Trapping"

Augsburg chemists present a new technology for compressing, storing and transporting highly volatile gases in porous frameworks/New prospects for gas-powered vehicles

Storage of highly volatile gases has always been a major technological challenge, not least for use in the automotive sector, for, for example, methane or...

Im Focus: Disrupting crystalline order to restore superfluidity

When we put water in a freezer, water molecules crystallize and form ice. This change from one phase of matter to another is called a phase transition. While this transition, and countless others that occur in nature, typically takes place at the same fixed conditions, such as the freezing point, one can ask how it can be influenced in a controlled way.

We are all familiar with such control of the freezing transition, as it is an essential ingredient in the art of making a sorbet or a slushy. To make a cold...

Im Focus: Micro energy harvesters for the Internet of Things

Fraunhofer IWS Dresden scientists print electronic layers with polymer ink

Thin organic layers provide machines and equipment with new functions. They enable, for example, tiny energy recuperators. In future, these will be installed...

Im Focus: Dynamik einzelner Proteine

Neue Messmethode erlaubt es Forschenden, die Bewegung von Molekülen lange und genau zu verfolgen

Das Zusammenspiel aus Struktur und Dynamik bestimmt die Funktion von Proteinen, den molekularen Werkzeugen der Zelle. Durch Fortschritte in der...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Conference to pave the way for new therapies

17.10.2018 | Event News

Berlin5GWeek: Private industrial networks and temporary 5G connectivity islands

16.10.2018 | Event News

5th International Conference on Cellular Materials (CellMAT), Scientific Programme online

02.10.2018 | Event News

 
Latest News

RUDN chemist tested a new nanocatalyst for obtaining hydrogen

18.10.2018 | Life Sciences

Massive organism is crashing on our watch

18.10.2018 | Earth Sciences

Electrical enhancement: Engineers speed up electrons in semiconductors

18.10.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>