Tag Archives: neurons

If you imagine each synapse as a door to another room….

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(from an email)

Brain tissue is a problem, but new brain pathways do spring up. Also, the current research seems to indicate that music thinking is a precursor to language, so it’s deeply embedded.

Well, those new synaptic pathways are also a problem for epileptics, as synapses connect in ways they shouldn’t and rerouting around synapses that should be connecting, thereby sundering the neuronal pathways to parts of the brain. It’s as if a neuron that had one hundred possible connections now has only five possible connections. If you imagine each synapse as a door to another room, suddenly ninety-five rooms have been locked shut, and everything within them is now unavailable forever. That is the impact partial seizures have on our brains, a few neurons at a time. When you realize that entire behaviors can be the result of a handful of connected neurons, it is amazing just what can be lost with even a virtually invisible seizure. A seizure is like a power surge in an electrical system, arcing currents and burning out circuits and wires and damaging machinery. As the temporal lobe seems to be much more vulnerable to this than the frontal lobe, every time an epileptic has a partial TLE seizure, some of the pathways are sundered and information is lost forever. Most we are not aware of. It can take decades to realize things are missing, though I’m sure the vast majority we have no idea we lost at all, simply because you can’t remember what you no longer remember.

I flunked out of pre-Algebra

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I flunked out of pre-Algebra in high school, so they had me take it in summer school where I passed with–I kid you not–a D minus. I think it was a mercy D-minus. I have an excuse, though, because whatever thought processes are used in any math beyond basic arithmetic sets off petit mal seizures and I end up out of it and nauseous. It took me years to figure this out, though. I thought I just hated math.

My IQ test results must have been interesting. I have no idea what score (or scores) I received, but I probably did well on the language stuff, and the basic arithmetic stuff, then bottomed out when it went beyond that. I remember taking an IQ test in high school. They’d herded us all into the auditorium and handed out the test sheets. I was whizzing through the language section thinking I was smart, then made it through the adding and subtracting easily enough, but then it began to get abstract and I began to get fuzzy. I never thought much about it though. Decades later the reason dawned on me one boring day at work when I started one of those online IQ tests. Those were all the rage at the time, one of the first annoying internet trends. This was years ago. As soon as it got to the more advanced questions with shapes, etc, my brain fizzed out and I felt sick. Limbs go numb, tongue heavy, and this fuzzy thickness descends and a sort of creeping nausea comes on. Ah ha, I thought to myself, and have avoided anything like that since. Can’t believe it took me thirty years to figure that out. The exact same thing used to happen to me in math class. I was a tough kid, though, not prone to complaining and figured everyone was like that too. Never imagined it meant something was wrong. My neurologist wasn’t the least bit surprised when we discussed it. It happens, he said. With epilepsy anything can happen. Some epileptics talk to God. Some have spontaneous orgasms. Me, algebra makes me sick. Not as fun, though probably less embarrassing.

I’m very leery of physics and philosophy for the same reason. I could never make head or tail out of either and I suspect it’s because trying to think like that sets off little electro-chemical firestorms in my frontal lobe which then spread to the temporal lobe and fuck shit up nicely. Maybe not, I may just not be bright enough to figure them out, but why take chances. Life sciences I’m fine with, though. Earth sciences, linguistics. My great regret in life is not pursuing a science career, but there was no way. You need math, and all I can do is simple arithmetic.

Certain kinds of modular maps will set me off too. Not long after I made the mistake of taking that IQ test I made the mistake of trying to read the stupid arty map in the Getty’s Top of the Hill garage. Hiply modular, way modular, expensively modular. A regular map just wouldn’t do, not at the Getty. I studied it for maybe fifteen seconds and suddenly I was in a haze, a little lost, and I couldn’t remember anybody’s name. My wife got us to our seats.

Anyway, I eventually learned that if trying to read anything made me feel out of it or sick, to stop reading it immediately. Took me thirty years of epilepsy to figure that out. Some writing will set me off too. It used to be a problem. Apparently over the years I’ve learned to write in ways that doesn’t set off my epilepsy. Couldn’t tell you how, but I rarely get sick writing anymore.

But I can take all the strobe lights ya got.

Apes with extraordinary cognitive abilities

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Once you realize that every single human being there is has inside their skulls the most complex thing that we know of in the entire universe, it gets a little weird. There are over 7 billion of these brains out there right now, all over the planet, each vastly more complex in its interconnectedness than the universe it exists in. Dig these numbers: a human brain has about 86 million neurons, and roughly ten times that many glial cells, or upwards of a billion. Each of these neurons fires five to fifty times a second and each of these neurons has up to ten thousand connections with other neurons. The estimates for the total numbers of synapses (i.e. the connections) between our neurons run from 100 trillion to 1,000 trillion (or one quadrillion). These synapses connect via dendrites (little filaments that grow from the surface of a neuron) and there are more dendrites than are used by neuron at any given time, so the potential number of connections could be one million billion (or one quintillion). That difference between that maximum total number of actual synapses (one quadrillion) and potential synapses (one quintillion), means the brain hasn’t come close to maximizing its capacity. And it means that the brain will continue to grow in complexity (and size). The human brain currently uses but a tiny fraction of its synaptic capacity. There simply isn’t enough to think about yet to fill it up.

83% of your brain is cerebral cortex, the thing that makes you you and people people. That cerebral cortex has grown at an astonishing speed evolutionary-wise. In just a couple million years it has expanded from chimp size (about a pound) to what it is now (about three pounds). Indeed it has grown so fast that it developed the folds you see in a brain in a jar, in order to maximize the number of neurons that could be crammed in the area available inside the skull. These folds increase surface area inside a limited space (or skull size), which increases the amount of neurons and synaptic connections between them. The size of our skull is limited by the dimensions of the human female’s birth canal. Indeed, the difficulty of human birth is due entirely to the size of the homo sapien sapien cerebral cortex. Were the woman’s pelvis able to widen further (it can’t, or at least natural selection isn’t capable of widening it at the same rate as a continuously expanding skull size)–or were it detachable like a snakes jaw (it isn’t), the human skull might be even larger, since apparently skull size is one of the things that can change quickly in our species through time (look at a collection of us and our predecessors to compare.)

Now about those billion glial cells. There’s ten times as many of them because they are much smaller than neurons. We used to think all these glia simply held neurons in place–it is vital that neurons remain in place to keep the synapses firing correctly, since synapses are not actually linked together but are just close enough for an electro-chemical charge to cross between them. But these glial cells also help to provide the neurons with nutrition, such as oxygen or the minerals such as potassium used in neurotransmission, which neurons exhaust quickly. And glia also helps with repairs and supplies the myelin which, like the rubber around a wire, shields the current running from one neuron to another via each synapse. But now it’s also known that much of the brains incredible plasticity is due to glial cells, and they are used in communication (and even breathing) and who knows what else. Glial cells, like everything else about the brain, just keep revealing more complexity.

And the complexity of all this is so vast that we are incapable of actually visualizing it. We fall back on huge numbers like quadrillion and quintillion, or compare it to the relative paucity of complexity in the known universe. What we have in our own skulls, and which is our very essence, we can barely understand. But every person you see has something in their heads that is more astonishing than the entire known universe. I can tell you that without truly comprehending it myself, because it is not comprehensible. We can understand it as a fact, an abstraction, but not actually appreciate just what it means. Like how we know what infinity is, but we can’t truly comprehend what it is. Our brains have myriad capabilities beyond our capacity to understand, because our brains are smarter than we are intelligent. After all, we are still just apes. Apes with extraordinary cognitive abilities, but still apes.

Hardwiring

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Damn epilepsy medicine is so expensive I’ve lowered my dosage a bit, which seems OK. Our brains shrink with age, the big giant twenty something thing squeezed into our skull at 23 or 24 has been reduced by maybe a per cent a year since then (tho’ not in every case), so maybe there are just less neurons for the medication to cover. Or maybe less synapses, the connections between the neurons, which is what causes the problem, all the dendrites–the little filaments–that spark so easily in an epileptic’s brain. But epileptic brains tend to hardwire as we age, so that we have less neurons open to us which might make us less prone to epileptic problems because hardened pathways can’t spark as easily. I think it’s sort of like an interstate that bypasses a lot of the local roads, if you can see that image. The more used neuronal pathways lose their synaptic connections with a lot of neurons in the process. Memory must get fucked up. (It has, actually). But who knows. All I know is I can get by on less meds than before. But, oddly enough, when I cut back my dosage my hypergraphia increases–this, for example–and I write for hours. Everyday, thousands and thousands of words. Which I suppose might be a good thing. Maybe. Some epileptic writers, I remember reading (I believe in The Midnight Disease by Alice Flaherty) learn how to take advantage of that hypergraphia by controlling the drug dosages….cutting back just a tad (or pushing the next dose back a couple hours) can be worth several thousand words. This doesn’t work if you suffer from tonic clonic (that is, grand mal) seizures. You don’t mess round with those. All that electricity shorting out everything, memories disappear, entire skill sets, parts of your personality, probably entire unwritten novels. But most epilepsy is simple partial seizures, localized, never losing consciousness, and although decades of that sort of epilepsy can do plenty of damage, it’s subtle, incremental, rarely noticed right away. You can risk holding off meds for those a few hours if you want to get some writing done. You learn to work it. It’s easier the older you are, as the more hardwired the neural pathways have become, the less prone the brain is to frying itself out unmedicated. It’s a learned skill, one never discussed with non-epileptics because it’s, well, weird. Maybe scary. Maybe creepy, even. But it certainly helps. Writers figure out all sorts of tricks to keep writing, this is just another. Not every epileptic is another Dostoevsky, the poor brilliant bastard, but we just might have an edge on the normal brained writers. We write like machines, just switch us on and words flow out, well past our bedtimes.