Monday, January 13, 2014

Nano-Tech: Big Problems, Small Answers - #1 Deep Brain Stimulation



There is a common misconception amongst the general populace that we only use 10% of our brains and the other 90% is a complete mystery. I am here today to assure you that the only mystery is where this myth could have originated because it is just that. A myth. If there’s one thing nature has taught us over our century or so of study in the world of evolution, it’s that nature doesn’t waste energy, (it isn’t human after all), in fact, it conserves it to such a degree its mind blowing.
Take for instance certain species of subterranean mammals like the naked mole rat. While they aren’t completely blind, nature didn’t see fit to give them the same set of photoreceptors as us. Why? Because they didn’t need it. They needed energy for other things, so evolution phased sight out.
Now don’t get me wrong, I’m not saying the human brain is slowly phasing out the human race, but to think there are parts we don’t use is just absurd.
But if you worded that statement a little differently to say we only understand about 10% of the brain, I might be able to rally behind you. And so wouldn’t many other scholars in the world of neuroscience. The scary truth is we really don’t know that much about it. We know what part stimulates breathing, motor function, and emotion. We even know with pinpoint accuracy where and how the pituitary gland influences our growth. But consciousness? Ha! Good luck with that.
While it’s true consciousness and how it works is a mystery unto itself and there are pieces of the brain we can tell are active but don’t know why, it’s not true that only a fraction of it is in use. In fact, just getting up, walking to the fridge, opening the door, and cracking a cold beer open to take a sip causes so many neurons to fire that under the right kind of imaging your brain would like an explosion at a power plant. So why am I telling you all this?
Well because in a world today dominated by Cancer research and a fast paced consumer entertainment market, disorders of the brain sometimes get swept to the wayside. Until those disorders of the brain begin to affect us on a large scale. A large scale like the one we have seen trending in the past decade.
It’s not that these diseases weren’t around before (most of them anyway) it was our way of dealing with them.
With advances in scanning techniques, treatment for once thought manageable yet un-curable diseases were being discovered. Perhaps amongst the most amazing of these advances in the realm of Neurosurgery was DBS, otherwise known as “Deep Brain Stimulation.”
Today we’re going to talk about this incredible surgery and its origins. We’ll also talk about some of the original techniques used to perform this “cutting-edge” (no pun intended) surgery in its infancy. We’ll also talk about the wealth of diseases it can currently cure, the ones they’re aiming it at, and the nano-technology that is going to take them there.

The Enemy


While any disease is the enemy of doctor’s worldwide, Parkinson’s is the Loki to the Neurosurgeon’s Avenger’s. As you can see in the graphic above there are a wide range of areas afflicted by Parkinson’s disease. What’s worse are the areas affected themselves. Because of the combination of misfiring neurons in the variety of locations the spastic micro-seizures accompanied with Parkinson’s disease (among many other disorders) can occur.
There are four symptoms related to motor function that are essential to PD. The first of which is the tremor. While it isn’t necessarily present at onset, this is one of the hallmarks of the disease, involuntarily spasms of the muscles. Bradykinesia, which is slowness of movement, comes next. The final two are rigidity of the muscles which can present in uniform ways or a cogwheel formation (a ratchet-like jerking of the extremity being analyzed as demonstrated in the video here), and then the final sign is postural instability. Postural instability is linked to falls amongst those affected by the disease.
On top of all that, there are neuropsychiatric symptoms linked to this disorder as well. Some are a result of the medications meant to control the symptoms, but some are thought to be resultant of the disease itself. Disorders such as insomnia, loss of appetite, depression, paresthesia (numbness or tingling in the extremities), these can all be warning signs of the onset. Why does this happen?
The short answer is Dopamine. Dopamine works like a messenger in the brain. It’s a neurotransmitter with a variety of tasks but whatever it’s delegated to do, at its core the primary function of Dopamine is to deliver a message. If abnormal levels of dopamine are produced or if production stops in certain areas catastrophic events begin to take place within the brain.
While scientists understand it’s the dopamine producing neurons to blame, when they die off, for the associated motor disabilities, they still don’t understand why the dopamine producing centers are dying. Mitochondrial dysfunction, oxidative stress, even environmental factors such as exposure to certain pesticides can be linked to Parkinson’s disease, but how the cells making dopamine are systematically destroyed is still a mystery.
What they do understand completely are the parts PD, and other diseases like it, are attacking. That’s why in recent years it’s been announced that DBS may be able to treat a variety of psychiatric disorders as well ranging from OCD and depression, to the more severe cases of schizophrenia and psychosis. OCD has been effectively treated in some instances already, giving physician’s the confidence to feel like this isn’t just a claim to get more grant money, this is real science.
Armed with this information and a fortress of cutting edge technology, doctors are now finally ready to suit up for that final confrontation with Lex Luthor. Like Superman, they may not understand Parkinson’s intentions, but they have a plan to put him behind bars.

DBS: Like An Architect For Your Brain



The brain is divided into two hemispheres, the right side and the left side. The left side is the logic center (i.e. math, science, reasoning.) while the right side is the creative cluster (poetry, arts, dance, etc.). But when the neural pathways in either side of the brain begin to deteriorate, as I mentioned before, bad things happen.
That’s where Deep Brain Stimulation (or DBS) comes into play. The way the brain works is extremely complicated and in order to explain it accurately and in full detail it would encompass the entirety of this article. So for the purposes of what we’re talking about today we’ll grossly oversimplify it and just say billions of tiny electrical pulsations are what make the brain do what it does. If you want the full scoop on how your three-pound thought box functions you can read what the guys at How Stuff Works cooked up by clicking here.
In the case of Parkinson’s disease where neurons are dying off, electrical impulses are having difficulty sending communications to other areas of the brain. When this happens the Axon’s that work like cable wires to carry the information don’t know what to say to the Dendrites, the ones who receive and interpret the information. When this happens the body begins to behave in a peculiar manner.
Think of it in terms of your television. The cable company acts like a cell body, gathering all the T.V. shows and arranging them in a digestible format for everyday viewers. The T.V. shows signal is then transmitted down the cable line which in the case of the brain would be the Axon. Its final destination is your cable box which would be the Dendrite, which then interprets that information into a picture for your T.V. or in the case of a Neuron, a command to lift your arm.
When Parkinson’s attacks, the cable company shuts down. There are no signals coming in or out down the wire to reach to your cable box. Because of this the television only displays static and eventually your interest dies out. Think of the Neuron like your interest in waiting for the cable company to fix the T.V. Without a signal it just dies.
The cause of this neuron death is widely unknown but research continues every day. What we do know is how to manipulate the electrical signals that are no longer transmitting. If the neurons function like a cable company to a T.V. then DBS is the Consumer’s Energy to get the lights turned back on. Let’s take a brief look at the history of psychosurgery to put in perspective just how far this truly remarkable science has come.

C’mon…It’s Not Like It’s Brain Surgery…


Psychology and the neurosciences are still in their infancy as far as medical fields go. Neurosurgery is even younger than that. Part of it stems from the limitations of technological advances, but the other part of it is the simple fact that we just didn’t understand the brain. We knew it was essential in diagnosing disorders like schizophrenia and various dyskinesia’s (involuntary muscle movement) associated with disorders like Parkinson’s and Palsy but we had no idea how.
Enter Dr. Gottlieb Burckhardt. In 1888 he performed six brain surgeries. But his instruments were crude and his methods, while good intentioned, were horrifyingly misguided. What ended up happening is two patients showed no change, two patients became catatonic mutes, another one died, but ONE GOT BETTER!!! He tried to publish his findings with a 50% success rate but instead received nothing but haughty laughter and hostility from his peers.
Then in 1910 another doctor in Russia took up the scalpel to three mentally ill patients. He attempted to redo Dr. Burckhardt’s earlier gamble with neurosurgery but collided with the same wall his predecessor had. The surgeries failed and in 1912 a scathing article was published demonizing Gottlieb’s original work quoting, “We have quoted this data to show not only how groundless but also how dangerous these operations were. We are unable to explain how their author, holder of a degree in medicine, could bring himself to carry them out...”
But yet he failed to mention that just two years prior he attempted to do the same thing…
Nonetheless, the Russian physician, Dr. Ludvig Puusepp changed his tune to the sound of retraction sharp in the 1930’s. As medical technology had advanced, as well as an understanding of the human mind, psychosurgery was becoming a viable option. In 1937, apparently forgetting he’d ever laughed Dr. Burckhardt off the world stage, he returned to the surgical theatre to help lead a new era of doctors in this unique field of study.
That’s when Portuguese neurologist (and inventor of the term psychosurgery) António Egas Moniz decided it was time for him to “cut in”. (hee hee). See while Dr. Burckhardt and Dr. Puusepp were trying to dig a trench around the cortex and sever the connections they thought were creating the problem, Moniz was taking a whole different approach. He determined that the only way to cure these patients was to remove the frontal lobe, thus giving birth to the lobotomy or as it was called then, leucotomy.
Now…to say the medical community found the lobotomy to be controversial and crazy to consider a viable treatment option is like saying that, “The Hebrew population in 1930’s Poland had mixed feelings about Hitler.” In short, it’s an understatement.
The problem didn’t stem from the method itself; in fact, lobotomies were performed to the ends of mixed results for quite some time. The problem lied in the fact that the patient receiving the operation didn’t really have a say in the matter. In those days, once you were institutionalized, you were officially at the mercy of your captors. In this case, the doctors.
By the 1950’s antipsychotic medications were becoming available and the lobotomy (thankfully) began seeing a steady decline. It wouldn’t return the livelihood of the some 20,000+ people that had been forced to undergo the surgery, but at least it would prevent anyone else from having to go through the barbarism of it again.
But this raised a new problem. If we can’t cut the bad wires to stop it, and if we can’t remove the fried circuit entirely then what do we do? Ablate the hell out of it course! In the 1940s till the late 80s, Neurosurgeons decided that if removing the parts of the brain that caused these ill effects wasn’t going to work, then maybe slicing and burning them would.
While lesioning (making precise incisions in targeted areas of the brain so as to achieve a desired effect within the patient) may not have been the best thing for patients, by 1987 it had paved the way for a new form of therapy. Deep brain stimulation. This technology would revolutionize the way we viewed the brain, the techniques used to assess, diagnose, and treat psychiatric disorders, and for the first time, it would seem to provide doctors with a means to fight back.
The enemy…the disease, was no longer invincible.

Hey! That Hertz!


 These last few decades have been great ones for science. We’ve seen advances in medicine, climatology, genetics research; in fact, we’ve made such strides in these areas we’ve had to create all new niche areas of study to just be able to properly encompass and give attention to it all. But as scientific disciplines get bigger, it seems the method of delivery gets smaller.
Before Benabid and Pollak in 1987 discovered that targeted electro-currents to the brain could re-fire the damaged neurons thereby alleviating tremor symptoms, our answer was to hack & slash our way through. These two men decided another; more delicate answer was needed to the burning questions of the brain. So what was their solution? Shock the crap out of it.
As we mentioned before the only form of dealing with movement disorders until this time was lesioning and that was dangerous and irreversible. Dr. Benabid wanted to find another method; one that could be undone should unforeseeable consequences take place. What he discovered was the effect of high frequency on the brain.
It wasn’t the first time electricity had been used in direct contact with the brain. In fact, using electrical pulses to render areas of the brain useless was a popular tactic used by doctors for lesioning already. But by changing the output of the current, it was possible to, in a sense; turn the non-working parts of the brain back on without causing permanent damage. However it was unfeasible for a patient to walk around with an open skull and a cattle prod just to keep from falling prey to the tremors of PD. They needed a constant delivery mechanism, one that could be installed through surgery, monitored and taken out should problems arise, and be altered as new technology became available. To say this seemed daunting is to say the Pyramids are big. It doesn’t encompass the scope of it even close to accurately.
Early DBS surgery was terrifying to the patient. First and foremost, it’s brain surgery. The thought of someone chiseling inside my brain with scalpels and drills doesn’t remotely appeal to me. To make matters worse the surgery took around 4 to 6 hours to complete. Now that doesn’t sound so bad until you find out that you have to stay awake the whole time.
In order for doctors to monitor the patient and make sure the leads were doing more good than harm, the patient would have to remain conscious in order to answer questions. In a video of a New York City police officer who underwent this surgery, Mike not only remains conscious, but when asked questions by the doctor, he responds in Russian. When the doctor calls attention to this, Mike jokingly states, “Well you must be doing something right I’m learning Russian!” (I absolutely adore this guy, its brain surgery so parts of the video are a little graphic but his courage is definitely worth the watch! Check out his story hereon YouTube.)
But even though Mike was willing to take the risk to make a change, the thought of being awake while doctor’s installed a car battery in your brain was terrifying to most. First they have to drill a hole in the skull cap. Wire leads are run along the back of the skull and down into the chest cavity. A screw is fixed in the skull in order to hold the leads in place. And that’s just the reader’s digest version of the first surgery.
The second surgery involved a battery pack, like a pacemaker, being installed in the chest to hook the leads to. Luckily this second surgery was one doctor’s were used to and the patient could be anesthetized for this one. But trying to convince patients on undergoing the first one was a tough sell. Because of this the process, while not exactly ignored, wasn’t highly recommended by physicians because medication was able to manage the disease in the early stages. DBS wasn’t readily recommended until the later stages of the disorder.
However thanks to an ever progressing world of technology, DBS fears may fall to the wayside and become a thing of the past. Patients no longer have to be awake during the surgery (which is a huge plus) thanks to new forms of imaging and scanning, and because of nanotechnology and robotics, the big problems doctor’s faced in the past are becoming much smaller as we move into the future.

The Shocking Future of SWCNTs


SWCNT’s (Single-Walled Carbon Nanotubes) and MWCNTs (Multi-Walled Carbon Nanotubes), are rather unique little inventions. Depending on the way you arrange the molecules in them, the structure can be used for a variety of tasks. For instance, a certain arrangement yields a structure stronger than steel but is six times lighter. This would be extremely useful for devices such as body armor for the military or lighter vehicles for the daily commuter. But for the purposes of this article we’re going to talk about SWCNT’s being used a different way, as microprocessors.
While much research is needed on Carbon Nanotubes still, one thing is abundantly clear. They have electrically conductive properties, and what’s more, they have actually been found to repair the damaged links between neurons in the brain. To put it in perspective let’s recycle our original analogy with the cable company.
With early DBS treatments, metal conductors and wire leads were required and had to be attached to a battery pack. This whole process is long, drawn out, and while strides have been made to accommodate those afflicted, having these bulky artificial parts inserted into your body can over time wear on a person. So if we make the pacemaker the cable company, the wires the Axons, and the brain the T.V. screen, SWCNT’s are the electrical tape used to make a patch.
Instead of using the complex procedure of leads and battery packs, Carbon Nanotubes are capable of natural conduction if the atoms are arranged in the right formation. Because of this they are able to slip into the areas that have burned out and respark the connections in order to send signals to the rest of the body once more. The surgery is as minimally invasive as one can imagine given the miniscule size of the Nanotubes. However, there are issues with it. For example…

There are three fundamental obstacles to developing reliable neuroprosthetics: 1) stable interfacing of electromechanical devices with neural tissue, 2) understanding how to stimulate the neural tissue, and 3) understanding what signals to record from the neurons in order for the device to make an automatic and appropriate decision to stimulate. The new carbon nanotube-based interface technology discovered together with state of the art simulations of brain-machine interfaces is the key to developing all types of neuroprosthetics -- sight, sound, smell, motion, vetoing epileptic attacks, spinal bypasses, as well as repairing and even enhancing cognitive functions.” Read more here.

While these are all still in the testing phase it’s impossible to deny that the future of this technology is promising. Only time will tell if Carbon Nanotubes will be able to deliver on the theories scientists have proposed for them. One thing is certain though, if disease itself is capable of feeling fear, it should. And the weapon to fear is Nanotechnology.

-       Ryan Sanders

I hope you enjoyed this article on Deep Brain Stimulation. If so please share it around on Facebook and Twitter. If you would like to know more about DBS, SWCNT’s, or anything else discussed in this article, feel free to follow any of the links below. As always, happy learning!












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