Saturday 15 January 2022
I am re-watching the lectures from last term as I prepare for an exam next week which is worth 10% of my Masters degree in neuroscience. Here is a typical piece of narrative, from a lecture about how the brain learns:
“The NDMA subclass of ionotropic glutamate receptors has long been known to serve as a coincidence detector that determines when both pre-synaptic neurons and post-synaptic neurons are active around the same time thereby meeting the conditions under which Hebbian synaptic potentiation should occur, and it does this because it is both ligand gated, which means that glutamate binds to it in order to open the ion channel, that allows positively charged calcium ions to flow from outside the neuron to inside the neuron; but it is also voltage dependent, which means that the post-synaptic membrane has to be depolarized, i.e. the post-synaptic cell has to be active for this ion channel to open…..”
The crazy thing is that I actually understand what this means. Even my ageing, disease ridden brain, is a remarkable learning engine, evidently still able to acquire a whole new language, and put it to use.
In my student essays I now use fancy words like aetiopathogenesis, magnetoencephalography, xenotransplantation, and single nucleotide polymorphism, and occasionally I possibly even use them in the right context.
At first sight this new language looks impenetrable but it does make sense. For example, there are a lot of compound words, like in German. So if you take “patho” which means disease, you can combine it with “histo”, which means tissue, to create ”histopathology” which means the study of the effect of diseases on tissue. If you take “aetio”, “patho” and “genesis” you get “aetiopathogenesis” which means the cause and development of a disease. Biology and medicine are complicated, so they tend to need a lot of fancy terms. The human brain is particularly complicated, so neuroscience adds a lot more words to the lexicon.
Neuroscience is also fascinating. Indeed, I find myself getting distracted from my goal of getting into neurodegeneration research because there are so many other interesting things going on: awesome technology like fMRI and PET for neuroimaging; the incredible process of brain development from single cell to 86 billion neurons and an astonishing 100 trillion connections between them; many as yet unsolved mysteries like memory formation, sleep, placebos, visual perception, psychoses and biggest of all, how does consciousness arise?
I’ll be sure to write more about this stuff another time, but for now, I’d better get back to learning and memory, the connectome and in vivo cell reprogramming…
