Quantitative MRI to observe the thalamus

A small cerebral structure buried deep in the middle of the brain, the thalamus plays an important role in the integration of sensory information, particularly a part of it called the lateral geniculate body (CGL), which is essential for visual healing. Information from the retina. Simply put, it acts as a bridge between the eyes and the cerebral cortex.

a brain structure that is difficult to study

Because of its small size and location in the brain, CGL is not easy to study. So far, most of what is known about this brain structure comes from invasive studies in primates (non-humans). Conventional MRI is not of sufficiently precise quality to fully capture the subtleties between brain tissue of the different sub-layers that make up the CGL, and it is nearly impossible to study without resorting to invasive methods because it is buried so deeply in the brain. Is.

Quantitative MRI for non-invasive observation

A team from the Technical University of Dresden in Germany (later abbreviated as TU Dresden) had the idea to attempt to observe CGLs not with conventional imaging techniques, but using a more recent method: quantitative MRI. Christa Müller-Eckt, a doctoral student at TU Dresden and one of the study’s authors, explains that “Unlike conventional MRI, the purpose of quantitative MRI is to measure the physical properties of the tissue rather than just the intensity of the image.“She specifies that”These magnetic physical properties depend on the type and structure of brain tissue, i.e. they differ for example for white matter, gray matter and cerebrospinal fluid.“Quantitative MRI therefore allows researchers to observe brain structures that would be invisible in conventional MRI … exactly the case of the thalamus!

See also  Cervical cancer screening campaign has been started

Christa Müller-Eckt and the rest of the team thus decided to measure a parameter called “quantitative T1”, which the researcher describes as “Particularly sensitive to the amount of white matter in brain tissue, especially myelin.“Their objective was to oversee not only the CGL, but also its two main sub-sectors:”Although both are composed of the same type of tissue (ie subcortical gray matter), studies in invasive animals have told us that cells in these two subcortical regions differ in the amount of material. The white that is in them.

two different viewable sub-areas

And it worked! “We were thrilled to learn that the two sub-regions of the CGL could actually be distinguished based on the amount of myelin in living humans through quantitative measurements,“indicates the researcher. Indeed, as indicated by their results published in the journal neuroimage, this new method allowed them to identify two distinct components in quantitative measurements, respectively, corresponding to two subregions of the CGL: a dorsal subdivision with high myelin density, and a ventral subdivision containing less white matter.

Paving the way for a better understanding of dyslexia

These results pave the way for a better understanding of the essential structure of the thalamus. Alterations in certain subregions of the CGL have been associated with several disorders in humans, for example dyslexia, a specific learning disorder with reading deficits. However, the role of these subregions in dyslexia has so far been studied only in post-mortem human samples, due to the difficulty of their access: this method of observation does not allow us to study the operation of the structure in question, and Its activity in real time. The German team hopes that quantitative MRI will allow us to study this structure in depth, both in healthy people and in people with, for example, dyslexia, to better understand this disorder.

See also  Climate change: Earthquake ‘hack’ reveals scale of ocean warming

More broadly, according to Christa Muller-Ext, “Quantitative MRI looks very promising for visualizing brain structures (and structures) composed of the same type of tissue, but with different compositions, such as the CGL and its sub-levels.“She specifically cites the medial geniculate body (CGM), which is equivalent to the CGL but for auditory pathways:”It will be very interesting to see whether subregions of the CGM can also be observed in quantitative MRI.

You May Also Like

About the Author: Abbott Hopkins

Analyst. Amateur problem solver. Wannabe internet expert. Coffee geek. Tv guru. Award-winning communicator. Food nerd.

Leave a Reply

Your email address will not be published. Required fields are marked *