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 Antibiotic resistances spread faster than so far thought
18.02.2019 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht The Lypla1 Gene Impacts Obesity in a Sex-Specific Manner
18.02.2019 | Deutsches Zentrum für Diabetesforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Light from a roll – hybrid OLED creates innovative and functional luminous surfaces

Up to now, OLEDs have been used exclusively as a novel lighting technology for use in luminaires and lamps. However, flexible organic technology can offer much more: as an active lighting surface, it can be combined with a wide variety of materials, not just to modify but to revolutionize the functionality and design of countless existing products. To exemplify this, the Fraunhofer FEP together with the company EMDE development of light GmbH will be presenting hybrid flexible OLEDs integrated into textile designs within the EU-funded project PI-SCALE for the first time at LOPEC (March 19-21, 2019 in Munich, Germany) as examples of some of the many possible applications.

The Fraunhofer FEP, a provider of research and development services in the field of organic electronics, has long been involved in the development of...

Im Focus: Regensburg physicists watch electron transfer in a single molecule

For the first time, an international team of scientists based in Regensburg, Germany, has recorded the orbitals of single molecules in different charge states in a novel type of microscopy. The research findings are published under the title “Mapping orbital changes upon electron transfer with tunneling microscopy on insulators” in the prestigious journal “Nature”.

The building blocks of matter surrounding us are atoms and molecules. The properties of that matter, however, are often not set by these building blocks...

Im Focus: University of Konstanz gains new insights into the recent development of the human immune system

Scientists at the University of Konstanz identify fierce competition between the human immune system and bacterial pathogens

Cell biologists from the University of Konstanz shed light on a recent evolutionary process in the human immune system and publish their findings in the...

Im Focus: Transformation through Light

Laser physicists have taken snapshots of carbon molecules C₆₀ showing how they transform in intense infrared light

When carbon molecules C₆₀ are exposed to an intense infrared light, they change their ball-like structure to a more elongated version. This has now been...

Im Focus: Famous “sandpile model” shown to move like a traveling sand dune

Researchers at IST Austria find new property of important physical model. Results published in PNAS

The so-called Abelian sandpile model has been studied by scientists for more than 30 years to better understand a physical phenomenon called self-organized...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Global Legal Hackathon at HAW Hamburg

11.02.2019 | Event News

The world of quantum chemistry meets in Heidelberg

30.01.2019 | Event News

Our digital society in 2040

16.01.2019 | Event News

 
Latest News

Terahertz wireless makes big strides in paving the way to technological singularity

19.02.2019 | Information Technology

Researchers find trigger that turns strep infections into flesh-eating disease

19.02.2019 | Health and Medicine

Light from a roll – hybrid OLED creates innovative and functional luminous surfaces

19.02.2019 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>