Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Surprising network activity in the immature brain

25.10.2018

Developing brain networks act locally to build globally

One of the outstanding mysteries of the cerebral cortex is how individual neurons develop the proper synaptic connections to form large-scale, distributed networks. Now, an international team of scientists including researchers from Goethe University and the FIAS have gained novel insights from spontaneously generated patterns of activity by local networks in the early developing visual cortex. Apparently these form the basis for long-range neural connections that are established through brain activity over the course of cortical development.


Spatial patterns of spontaneous correlation (example in figure on the left) in the immature visual cortex prior to eye-opening are distributed across several millimeters and resemble the layout of the response properties (example on the right) of visual cortex after eye-opening.

Now, as published in Nature Neuroscience, scientists at the Max Planck Florida Institute for Neuroscience, Frankfurt Institute for Advanced Studies, Goethe University of Frankfurt, and the University of Minnesota have investigated the visual cortex of the ferret, an ideal model system to explore the early development of networks in the cortex.

These are composed of thousands of neurons and are distributed over millimetres of the cortical surface. In the visual cortex, network activity encodes specific features of the visual scene like the orientation of edges and the direction of object motion.

By using calcium imaging techniques, the scientists were able to visualize with unprecedented resolution spontaneous activity patterns, i.e. patterns not produced by visual input. To their great surprise, the spontaneous activity patterns were highly correlated between distant populations of neurons – and in fact were so highly correlated that the activity of small populations of neurons could reliably predict coincident network activity patterns millimetres away, and these correlation patterns beautifully predicted the patterns of network activity evoked by visual stimulation.

In their next step, the researchers used this remarkable correspondence of spontaneous and visually-evoked network patterns to find out how the interaction of networks developed in the immature brain.

By looking at the state of spontaneous activity patterns prior to eye opening, they expected to see a striking difference in the patterns of spontaneous activity because the long-range cortical connections that are thought to be the basis for distributed network activity patterns are absent in the immature cortex.

To their surprise, they discovered robust long-range patterns of correlated spontaneous activity prior to eye opening, and found that they extended over distances comparable to what was seen in the mature brain.

Confronted with this paradox, the researchers first considered whether the correlated activity patterns could be spreading through chains of local cortical connections, similar to a forest fire. To test this intriguing possibility, Matthias Kaschube, Professor for Computer Science at Goethe University and Fellow at the Frankfurt Institute for Advanced Studies (FIAS), and his doctoral student Bettina Hein, built a computational model of the neural circuitry in the early visual cortex.

They found that by using a set of parameters that are consistent with the organization of local cortical connections, the model could precisely reproduce the patterns of spontaneous long-range correlations they had observed experimentally, without the need for long-range connections.

Taken together, these results suggest that long-range order in the early developing cortex originates from neural activity driven by short-range connections. In other words, local connections build a network activity scaffold. Following the well-accepted plasticity rule ‘what fires together wires together’, activity mediated by local connections can then guide the subsequent formation of long-range network connections. In a twist of the oft-used phrase, ‘think globally, act locally’, developing cortical circuits act locally to achieve global effects. Future studies will test the prediction that activity dependent plasticity mechanisms shape the structure of long-range connections based on the instructive activity patterns derived from local cortical connections.

Publication:
Gordon B Smith, Bettina Hein, Dave E Whitney, David Fitzpatrick, Matthias Kaschube: Distributed network interactions and their emergence in developing neocortex (2018) Nature Neuroscience. http://www.nature.com/articles/s41593-018-0247-5

An image to download can be found here: www.uni-frankfurt.de/74522335
Caption: Spatial patterns of spontaneous correlation (example in figure on the left) in the immature visual cortex prior to eye-opening are distributed across several millimeters and resemble the layout of the response properties (example on the right) of visual cortex after eye-opening.
Credit: Bettina Hein

Further information: Professor Matthias Kaschube, Institute for Computer Science and Frankfurt Institute for Applied Sciences, Riedberg Campus, Tel. +49 69 798-47521, kaschube@fias.uni-frankfurt.de.

Current news about science, teaching, and society in GOETHE-UNI online (www.aktuelles.uni-frankfurt.de)
Goethe University is a research-oriented university in the European financial centre Frankfurt The university was founded in 1914 through private funding, primarily from Jewish sponsors, and has since produced pioneering achievements in the areas of social sciences, sociology and economics, medicine, quantum physics, brain research, and labour law. It gained a unique level of autonomy on 1 January 2008 by returning to its historic roots as a "foundation university". Today, it is among the top ten in external funding and among the top three largest universities in Germany, with three clusters of excellence in medicine, life sciences and the humanities. Together with the Technical University of Darmstadt and the University of Mainz, it acts as a partner of the inter-state strategic Rhine-Main University Alliance. Internet: www.uni-frankfurt.de

Publisher: The President of Goethe University Editor: Dr. Anne Hardy, Referee for Science Communication, PR & Communication Department, Theodor-W.-Adorno-Platz 1, 60323 Frankfurt am Main, Tel: (069) 798-13035, Fax: (069) 798-763 12531.

Wissenschaftliche Ansprechpartner:

Professor Matthias Kaschube, Institute for Computer Science and Frankfurt Institute for Applied Sciences, Riedberg Campus, Tel. +49 69 798-47521, kaschube@fias.uni-frankfurt.de.

Originalpublikation:

Gordon B Smith, Bettina Hein, Dave E Whitney, David Fitzpatrick, Matthias Kaschube: Distributed network interactions and their emergence in developing neocortex (2018) Nature Neuroscience. http://www.nature.com/articles/s41593-018-0247-5

Jennifer Hohensteiner | idw - Informationsdienst Wissenschaft
Further information:
http://www.uni-frankfurt.de

More articles from Life Sciences:

nachricht A new view of microscopic interactions
02.07.2020 | University of Missouri-Columbia

nachricht B-cell protectors
02.07.2020 | Max Delbrück Center for Molecular Medicine in the Helmholtz Association

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Gentle wall contact – the right scenario for a fusion power plant

Quasi-continuous power exhaust developed as a wall-friendly method on ASDEX Upgrade

A promising operating mode for the plasma of a future power plant has been developed at the ASDEX Upgrade fusion device at Max Planck Institute for Plasma...

Im Focus: ILA Goes Digital – Automation & Production Technology for Adaptable Aircraft Production

Live event – July 1, 2020 - 11:00 to 11:45 (CET)
"Automation in Aerospace Industry @ Fraunhofer IFAM"

The Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM l Stade is presenting its forward-looking R&D portfolio for the first time at...

Im Focus: AI monitoring of laser welding processes - X-ray vision and eavesdropping ensure quality

With an X-ray experiment at the European Synchrotron ESRF in Grenoble (France), Empa researchers were able to demonstrate how well their real-time acoustic monitoring of laser weld seams works. With almost 90 percent reliability, they detected the formation of unwanted pores that impair the quality of weld seams. Thanks to a special evaluation method based on artificial intelligence (AI), the detection process is completed in just 70 milliseconds.

Laser welding is a process suitable for joining metals and thermoplastics. It has become particularly well established in highly automated production, for...

Im Focus: A structural light switch for magnetism

A research team from the Max Planck Institute for the Structure of Dynamics (MPSD) and the University of Oxford has managed to drive a prototypical antiferromagnet into a new magnetic state using terahertz frequency light. Their groundbreaking method produced an effect orders of magnitude larger than previously achieved, and on ultrafast time scales. The team’s work has just been published in Nature Physics.

Magnetic materials have been a mainstay in computing technology due to their ability to permanently store information in their magnetic state. Current...

Im Focus: Virtually Captured

Biomechanical analyses and computer simulations reveal the Venus flytrap snapping mechanisms

The Venus flytrap (Dionaea muscipula) takes only 100 milliseconds to trap its prey. Once their leaves, which have been transformed into snap traps, have...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Dresden Nexus Conference 2020: Same Time, Virtual Format, Registration Opened

19.05.2020 | Event News

Aachen Machine Tool Colloquium AWK'21 will take place on June 10 and 11, 2021

07.04.2020 | Event News

International Coral Reef Symposium in Bremen Postponed by a Year

06.04.2020 | Event News

 
Latest News

International conference QuApps shows status quo of quantum technology

02.07.2020 | Event News

A new view of microscopic interactions

02.07.2020 | Life Sciences

B-cell protectors

02.07.2020 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>