What lies between grey and white in the brain
Making the superficial white matter visible in the living human brain


Date:
October 19, 2020
Source:
Max-Planck-Gesellschaft
Summary:
A multidisciplinary team has succeeded in making the superficial
white matter visible in the living human brain.



FULL STORY ========================================================================== Traditionally, neuroscience regards the brain as being made up of
two basic tissue types. Billions of neurons make up the grey matter,
forming a thin layer on the brain's surface. These neuronal cells are interlinked in a mindboggling network by hundreds of millions of white
matter connections, running in bundles, deeper in the brain. Until
very recently, not much was known about the interface between the
white and grey matter -- the so-called superficial white matter --
because methods were lacking to study it in living human brains. Yet,
previous investigations had suggested the region to be implicated in devastating conditions such as Alzheimer's disease and autism. Now
a multidisciplinary team led by Nikolaus Weiskopf from the Max Planck
Institute for Human Cognitive and Brain Sciences has succeeded in making
the superficial white matter visible in the living human brain.


==========================================================================
"We demonstrated that the superficial white matter contains a lot of
iron. It is known that iron is necessary for the process of myelination," explains Evgeniya Kirilina, first author of the study published in
Science Advances.

Myelin is what makes the white matter white. It's the fatty coating of
nerve cell axons that speeds up transmission of information through the
brain. The myelination process can occur throughout the lifespan but is predominant during development. In fact, the largest concentration of iron
the researchers found was in the superficial white matter in regions of
the frontal cortex, which happens to be the slowest developing structure
in the human brain. Incredibly, the human frontal cortex is not fully myelinated until the forth decade of life.

The key to the new method is MRI (Magnetic Resonance Imaging) but at
very high field strength. While typical clinical MRI scanners work at
1.5 or 3 Tesla, in terms of the strength of the magnetic field, the Max
Planck Institute for Human Cognitive and Brain Sciences houses a powerful
7 Tesla scanner. This, in combination with advanced biophysical model,
allowed the team to create very high resolution maps of the white-grey
matter border across the entire living brain. The accuracy of their submillimetre maps was assessed against classic and advanced histological methods involving physical dissection and analysis of post mortem brains.

The new method promises many further insights into the organisation of
the interface between white and grey matter. Evgeniya Kirilina adds,
"We hope the method can be used to increase our understanding of brain development as well as pathological conditions involving the superficial
white matter."

========================================================================== Story Source: Materials provided by Max-Planck-Gesellschaft. Note:
Content may be edited for style and length.


========================================================================== Journal Reference:
1. Evgeniya Kirilina, Saskia Helbling, Markus Morawski, Kerrin Pine,
Katja
Reimann, Steffen Jankuhn, Juliane Dinse, Andreas Deistung,
Ju"rgen R.

Reichenbach, Robert Trampel, Stefan Geyer, Larissa Mu"ller, Norbert
Jakubowski, Thomas Arendt, Pierre-Louis Bazin, Nikolaus Weiskopf.

Superficial white matter imaging: Contrast mechanisms and
whole-brain in vivo mapping. Science Advances, 2020; 6 (41):
eaaz9281 DOI: 10.1126/ sciadv.aaz9281 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2020/10/201019103503.htm

--- up 8 weeks, 6 hours, 50 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1337:3/111)