This is a diffusion spectrum MR image of human brain showing curvature of two-dimensional sheets of parallel neuronal fibers that cross each other at right angles. (c) Massachusetts General Hospital

The Human brain might be organized a whole lot simpler than previously thought. Imaging reveals 3-D grid structure

This is a diffusion spectrum MR image of human brain showing curvature of two-dimensional sheets of parallel neuronal fibers that cross each other at right angles. (c) Massachusetts General Hospital

This is a diffusion spectrum MR image of human brain showing curvature of two-dimensional sheets of parallel neuronal fibers that cross each other at right angles. (c) Massachusetts General Hospital

The most complex object on Earth is the human brain. However, even though it’s intertwined by billions of nerve fibers almost in a chaotic fashion, scientists who have used sophisticated mathematical analysis of advanced imaging data found that the neural pathways that carry electrical signals through the brain are arranged in a very simple manner, resembling a grid. This counter-intuitive finding suggests that the neural structure is extremely simple, underlying the complexity of the brain.

“We found the brain is built from parallel and perpendicular fibers that cross each other in an orderly fashion. Finding this kind of simple organization in the forebrain of higher animals was completely unsuspected,” says Van Wedeen, MD, of the Martinos Center for Biomedical Imaging at Massachusetts General Hospital, who led the study. “Knowing there is a simple plan that, modified by evolution and development, gives rise to all brains has implications for researchers working to build an atlas of brain connections, for pursuing investigation of how the brain develops and for expanding theories of how the brain works.”

This staggering conclusion was made after the researchers, lead by Van Wedeen of Massachusetts General Hospital in Boston, employed a variation of  magnetic resonance imaging (MRI) that harnesses the diffusion of water in brain tissue. Previous research which tried to map the neural pathways of higher order animals, like primates, had been challenging because  each pathway crosses many others within a small space, making them difficult to interpret.

Mapping the brain’s grid

A detail of a diffusion spectrum MR image of rhesus monkey brain showing the sheet-like, three-dimensional structure of neural pathways that cross each other at right angles. (c) Massachusetts General Hospital

A detail of a diffusion spectrum MR image of rhesus monkey brain showing the sheet-like, three-dimensional structure of neural pathways that cross each other at right angles. (c) Massachusetts General Hospital

The method employed by the researchers in the present study basically tracks the movement of water molecules, which they used to brain brain nerves, but at the same time also highlight where these fibres cross. Four species of non-human primates (rhesus monkeys, owl monkeys, marmosets and galagos), together with human volunteers, have had their brains analysed using diffusion spectrum MR imaging. Mathematical analysis of all crossing or adjacent pathways in the brains showed that these were either perpendicular or parallel to the original pathway. Lower primates, like the Galago bushbaby, had a much more evident grid structure, revealing sheets of parallel fibres running at 90 degrees to each another, however moving up towards the primate tree showed that the pathways became progressively slightly more curved, still the grid-like structure was still preserved in humans as well.

This new grid structure finding might explain how the brain evolved progressively this well, considering a tangled up structure would make it difficult for mutations to  increment changes in connectivity.

“I don’t think anyone suspected the brain would have this sort of pervasive geometric pattern,” Wedeen says. “Although our findings could be described as a new longitude and latitude for the brain, they’re also leading us to an entirely new understanding of how and why the brain is organized the way it is. The old image of the brain as a tangle of thousands of discrete, unconnected wires didn’t make sense from an evolutionary standpoint. How could natural selection guide each of those wires into more efficient, advantageous configurations?

“The very simplicity of this grid structure is the reason why it can accomodate the random, gradual changes of evolution,” he continues. “It’s easier for a simple structure to change and adapt, whether we’re talking about the big changes that occur across evolution or the changes that can occur during an individual’s lifetime – both the normal neuroplasticity associated with development and learning or the damage that results from injury or disease. A simple grid structure makes both evolutionary and develomental sense.”

All extremely interesting, and if proven correct, the findings could have some important consequences on future brain studies. However, diffusion MRI can’t detect nerve fibres directly, instead it reconstructs images based on the movement of water molecules in a magnetic field. This makes the data interpretative and subjected to interference factors.  The present study is sure to stir controversy, but all for the best – more effort will be directed towards studying neural pathways.

The findings were published in the journal Science.

 

6 thoughts on “The Human brain might be organized a whole lot simpler than previously thought. Imaging reveals 3-D grid structure

  1. Danielle Russell

    can make it all come together like that even after millions of years its just to complex and the chances are to small and once more look at the laws of physics like the law controlling the force of gravity if they were just a iota smaller are bigger the universe as we know it could not exist and therefor life could not exist so yes science has a lot of things right yet it seems to only strengthen my belief that a intelligent force controls it all

  2. Ioncloud9

    “Its just too complex (for me to understand)” FTFY.

    Just because you cant figure it out or comprehend it doesnt mean somebody else hasnt. Its too bad you dont see the beauty in evolution, especially with things like this.

  3. Asdf

    There certainly wasn’t any intelligent force behind the design of that awful run-on sentence.

  4. dovhenis

    Origin Of Nerved Organisms

     

    From

    http://universe-life.com/2012/02/03/universe-energy-mass-life-compilation/

     

    Life’s evolution, mass formats self-replication:

    RNA nucleotides Genes (organisms) to RNA and DNA genomes (organisms) to
    mono-cellular to multicellular organisms.

    Individual mono-cells to cooperative mono-cells communities, “cultures”.

    Mono-cells cultures to neural systems, then to nerved
    multicellular organisms.

     

     

    Dov Henis

    (comments from 22nd century)

  5. Andro ang Christopher

    Someone moderately intelligently designed the spambot which looked up that text based on the content of the article. Look at the username and link.

  6. Andro ang Christopher

    So you’re sure you know the absolute truth about whether it’s good or bad to appreciate the beauty in evolution? That’s refreshing to hear. :3

Leave a Reply

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