Tag Archives: Neuron

The Quest for the Holy Glial

Astrocyte - Astrocytes can be visualized in cu...

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If you plan to read only one book on brain this year, make it a point to read ‘The Other Brain’ by Douglas Fields. While most of us in the psycho-neuro field have been focusing on the neurons, there is a silent revolution that is taking place about our understanding of Glial cells and how they may be crucial to our understanding of many Brain related complications ranging from  infections like the prion disease to neuro-degenerative disorder to the brain cancers. Glias of various sizes and shapes have much to do with these and by narrowly focusing on the neurons we may be missing half the picture (literally).

But I would have not so heartily recommended this book to all psychology and neuroscience lovers, had it been another dry discourse meant to showcase one’s expertise or managed to just compile the most recent findings; – while filled with cutting edge scientific facts,  it is the ability of the author to weave that into a narrative , to get us not just deeply interested in this Glial quest but to feel ourselves as a part of this quest- this monumental understanding of that other 85% of our brain cells – that makes reading this book a riveting and fulfilling experience.

While I did know that Glias constitute the major part of our brain tissue, and that they are important in myelination and thus speedy conduction of Acton potentials , my knowledge of Glia was limited to this superficial account ; the many new things I personally learned included the fact below:

  • Brain cancers are due to Glia (as adult neurogenises is rare and strictly controlled)- seems a no-brainer when you think of it;
  • The different types of Glial cells ; how they look like (beautiful pictures)  and how microglia are actually the immune system of the brain .
  • Schwann Glia are only present in peripheral nervous system and Oligodendrocytes only in CNS– and while Schwann cells can help the growth post injury in PNS( they form a pathway that guides new axons) , Oligodendrocytes actually hamper the process and thus brain/spinal cord injury leads to irreversible damage.
  • Along the way I read a beautiful description of how an electron microscope actually looks like and how it feels to operate one to view the sections and the sectioning procedure.
  • The science as well as the politics behind the Prion infection mechanism discovery. How Gajdusek defied all odds to work with Papua New Guinea people.
  • Glias also do computations by using Ca2+ signalling and listen to  (and possibly modify) neuron conversations. How that is imaged using new technologies including optogenetics.

There are many more such golden nuggets spread all over the book and the writing style is pure joy to read. I’m still only half-way through the book, but thought of sharing my joy at finding such a good book with the mouse trap readers. the book does great timely service by highlighting the important glail research and making it mainstream. I hope more scientists study and understand Glias and that Glias become as much a part of our discourse as  neurons are and find their place in psychology and neuroscience textbooks.

Full disclosure: I received a free copy of the book for review by Simon and Schuster.

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neural developmental stages for dummies

Image of a fluorescently-labeled growth cone e...
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I’m no expert when it comes to complex questions like that related to neural development, but to my naive mind the major stages involved in neural development seem to follow the eight stages as outlined in in the eight stage evo-devo model.

The first stage is normally involved with the coming in being of a particular new form, in this case the birth and differentiation of a neuronal cell form its precursor stem cells.

The second stage typically involves motion and in this case refers to the migration of immature neurons from their birthplaces in the embryo to their final positions.

The third stage typically refers to connections and branching and in this case refers to the outgrowth of axons and dendrites from neurons.

The fourth stage is typically a social/ dormant sort of state and in this case refers to the guidance of the motile growth cone through the embryo towards postsynaptic partners.

The fifth stage typically is about achieving closure/integration/individuality and in this case refers to the generation of synapses between these axons and their postsynaptic partner.

After this the sixth ,seventh and eight stage refer to qualitatively different sort of development – that at synapse. We have synapse formation followed by changes in synaptic strength due to learning and memory; and finally the pruning of synapses to yield the best possible redundant neuronal system.

To me everything looks to follow the eight stage pattern; but does these major stages of neural development make sense to you too and seem to follow distinctive stage patterns?

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