Another Deep Brain Stimulation Blog

Someone is going to get a deep brain stimulation implant to improve their depression symptoms. It looks like they are going to document their progress on this blog (278-005 DBS Trial). Should be some interesting commentary.

So there's the start. I am patient 278-005 in a DBS study. My surgery is scheduled for December. I want to diary what's going on and what happens. I want to mainly for me - but also for anyone else suffering from depression - like Kara did for me - to remind us to not give up hope - there is always something else to try. And being a guinea pig? Well, that's ok too. I'll take my 4/9 chance for six months and my 2/3 chance after 6 months to feel better.

Thanks to Dr. Shock for the tip.

Brain Electrical Stimulation

NeuroNexus Technologies and Philips are teaming up to create smaller and more responsive deep brain stimulation devices. These devices will also be MRI friendly. Neuronexus has some experience in creating polymer and silicon based micro-electro-mechanical systems (MEMS). Better deep brain stimulation devices will likely last longer in the brain and interface better with the surrounding brain tissue. Future deep brain stimulation devices will continue to miniaturize as time goes forward. Here's the press release

By combining Philips Research’s strengths in microelectronics, signal processing, ultra-low power system design and miniaturization with NeuroNexus Technologies’ expertise in micro-scale electrode design and fabrication, the two companies aim to show the technical feasibility of highly programmable and MRI-safe deep brain stimulation devices. Their initial research will aim to meet the functional requirements of a deep brain stimulation device for the treatment of Parkinson’s disease. This is a degenerative disorder of the central nervous system that impairs people’s motor skills and speech, leading to a progressive loss in quality of life. Recent publications suggest that deep brain stimulation could also be suitable for treating psychiatric disorders such as clinical depression.

Deep Brain Stimulation Blog

I have recently come across a blog that has a person's first hand account of undergoing a deep brain stimulation implant procedure. Deep brain stimulation involves implanting an electrode like device deep inside the brain. The device delivers electricity to the surrounding brain tissue. He had the DBS device implanted to improve the symptoms associated with parkinson's disease. You can see the blog here, Focus on a Cure's Deep Brain Stimulation (DBS) Journal.

Beginning with the surgery on 9-30-08, the procedure went well as expected and without complication. From a clinical view point it was one of the most fascinating experiences I have ever had. In being awake I remember every second of the procedure and was interacting with the staff the whole time.

It sounds like he didn't have the best experience.

Following surgery other than being very sleepy, the following morning after all the ICU monitoring equipment was removed so I could be transferred to a regular neurology floor I was talking with my wife and I had a severe Gran Mal Seizure (A grand mal seizure — also known as a tonic-clonic seizure — features a loss of consciousness and violent muscle contractions.

I think in the future these types of procedures will continue to get safer and find a more widespread use among people with brain disorders.

Deep Brain Stimulation (DBS) for Depression

I have previously mentioned about deep brain stimulation (DBS) that has been used to improve people's mood. With deep brain stimulation, implants are implanted inside the brain by doing brain surgery. A new study has come out showing that a deep brain stimulation implant targeted to the subcallosal cingulate gyrus was able to relieve the symptoms of depression in depressed patients. The DBS implant quells overactivity in that specific part of the brain by delivery of controlled jolts of electricity. This is more evidence that deep brain stimulation can actually improve conditions associated with brain disorders. Researchers at Toronto Western Hospital treated 20 depressed patients with the DBS implants. They found that 60 percent of patients had a 50% or greater reduction in depressive symptoms, while 35% went into remission (meaning they had no depression symptoms). This is a fairly high response for treatment resistant patients. It appears the reduction in symptoms was also fairly long lasting, which is a major benefit to DBS implants.

“Our research confirmed that 60 per cent of patients have shown a clinically significant response to the surgery and the benefits were sustained for at least one year,” said Dr. Lozano. “The underpinnings of depression are poorly understood and this therapy, although not perfect, offers numerous advantages.”

I still think that deep brain stimulation as a treatment modality will be fairly limited in scope. Brain surgery carries numerous risks, including death. So many people would probably pass at getting this procedure performed. I think that the new deep transcranial magnetic stimulation may allow non-invasive targeting of the subcallosal cingulate gyrus. Deep TMS does not require surgery so the risks are much less than those associated with getting a DBS implant.

You can read another good article about the various electric treatments for brain disorders here.

Better Deep Brain Stimulation Implants

Deep brain stimulaton implants have shown a lot of promise for various brain disorders. Scientists are not exactly sure how these DBS implants work. They deliver targeted electrical stimulation, and this can change the activity of specific brain areas presumably by altering the firing pattern of neurons surrounding the brain implant. There are several problems, though, that are inherent to using these devices. A big problem with using deep brain stimulation implants is that they are very difficult to correctly position the devices to get a desired response. This is something that scientists have been working on to circumvent. Recently, researchers have created a new deep brain stimulation implant that can modify the amount of electricity given out more precisely. This will lead to a better therapeutic effect for patients with various brain disorders.

The chip for the device is shown to the left (PHOTO: Dr. Helen Mayberg). This device would be able to automatically change the pattern of eletrical stimulation to get the best result. Misplacement of deep brain stimulation devices can occur quite frequently. This often leads to unintentional negative effects on behavior or mood. So this device will be able to detect the activity of the surrounding brain tissue and then correctly adjust itself to make sure it was giving out the right electrical output. This is similar to the robotic brain implant that I mentioned previously. I think progress in this area should continue and this will lead to deep brain stimulation devices which are much more refined. Science is moving towards a greater control of the electrical activity of the brain and this should be a boon for brain disorders.

New Deep Brain Stimulation Area for Parkinson's

A new report in the June issue of Neurology, Neurosurgery & Psychiatry shows that deep brain stimulation targeted to a different brain area can improve the symptoms of Parkinson's disease. Parkinson's disease is a degenerative disorder that usually leads to movement problems. Deep brain stimulation (DBS) involves imlanting a small electrode device inside the brain to send controlled jolts of electricity. For this specific study the researchers targeted the Ventral intermediate (Vim) thalamic region. Previous studies with deep brain stimulation have shown the it can be effective for certain symptoms of parkinson's disease, but improvement in essential tremor have been inconsistent.

The researchers followed the patients with the deep brain stimulation devices for approximately 6.6 years after they underwent surgery. The tremor scores as measured by a common parkinson's rating scale were improved more when the deep brain stimulation device was turned on compared to when it was turned off. Other motor symptoms scores were not improved as much, indicating this treatment is relatively selective in its beneficial effects. This may become a new treatment modality for improving the symptoms of parkinson's disease. You can read the abstract of the study at this site.

Results: Tremor was still effectively controlled by DBS and appendicular rigidity and akinesia remained stable compared with baseline. Axial scores (speech, gait and postural instability), however, worsened, and in parallel the initial improvement in activities of daily living scores at the 1 year follow-up had disappeared at 6 years, despite sustained improvement of tremor. Remarkably, neither daily doses of dopaminergic medication nor fluctuations and dyskinesias had changed at 6 years compared with baseline in this particular patient group

Source:
J Neurol Neurosurg Psychiatry 2008;79:694-699

Brain Surgery

The NeuroArm is a surgical robot that can perform neurosurgery inside an MRI. I already mentioned this new technology in a previous post. Researchers have successfully used this robot to remove a woman's brain tumor. This device could also potentially be used as a safer method of introducing deep brain stimulation implants into the brain. As I mentioned previously, the death rate of neurosurgery can be relatively high. So this robot neurosurgery device would likely reduce the risk of any such occurance.

In other news, the associated press is reporting about the success that doctors have had using deep brain stimulation in treating depression.

Still, the early results are promising. Dramatic video shows one patient visibly brightening as doctors turn on her brain pacemaker and she says in surprise: "I'm starting to smile."

You can watch an interesting short video about the neuroarm below.

The iPlant

The iPlant is a hypothetical brain implant that would be similar to the deep brain stimulation devices currently being tested. It has been proposed by Christopher Harris in an article entitled "Program Yourself". The idea would be to place an implant device in the ventral tegmental area (VTA), substantia nigra and the raphe nuclei. Doing this would allow the regulation of mood altering neurotransmitters like dopamine and serotonin. The discussion about this device and its potential uses is fairly interesting.

The main problem I have with this implant is that increasing serotonin or dopamine is a relatively non-selective method of manipulating brain functioning. Changing these neurotransmitter concentrations can have a drastic effect on many different brain functions as there are multiple serotonin and dopamine receptors. So I think placing an implant device in these areas would have many unintended effects. I tend to think that implant devices in brain regions directly correlated with specific symptoms would be a better idea, such as placing a DBS device in the nucleus accumbens. Christopher Harris brings up many good points on his website. He suggests several potential problems for this type of technology.

"Involuntary mind control: Many people worry that the iPlant could allow complete control over someones thoughts and behavior against their will (similar to The Manchurian Candidate). However, let's not overstate the level of control that brain stimulation reward could give you over another person. The function generates motivation by repeatedly reinforcing specific, simple behaviors."

With this implant there is certainly the potential for mind control and the stimulation of the reward center has already been used to control rats. Imagine a government like China requiring its citizens to get a brain implant in their pleasure center. The government would be able to dole out pleasure to its citizens on the basis of them performing tasks that the government wanted. China is already building a high-tech police state for surveillance of its citizens. China is collecting as much data on its own citizens as is humanly possible. Perhaps in the future this will include using brain scanning technology and brain implants for complete knowledge and control of every aspect of its citizens lives. A totalitarian government could implant multiple brain implants. One implant might inflict pain on the individual while another pleasure. Other implants might increase a person's concentration or decrease the need for sleep and other unnecessary activities.

A large central government computer could collect data on its citizens and then optimize brain stimulation toward a desired societal effect such as increased economic output. The government could make previously unrewarding tasks such as menial labor intensely pleasurable while simultaneously discouraging activities considered wasteful of the government's resources. Activities deemed uncessary by the government (such as sex) could be minimized by making them unrewarding. So people would work hard to improve the fitness of the government as an entity instead of the individual. This might be a move toward group evolutionary selection as the country as an entity would now become the unit of selection and the individuals would become mere cogs in the workings of the country superorganism. The government would select activities for the individual which enhanced the "fitness" of the government as an organism. Surprisingly, I think this could also potentially lead to what Nick Bostrom has described as "Scenario I: The Mindless Outsourcers".

"We can thus imagine a technologically highly advanced society, containing many sorts of complex structures, some of which are much smarter and more intricate than anything that exists today, in which there would nevertheless be a complete absence of any type of being whose welfare has moral significance. In a sense, this would be an uninhabited society. All the kinds of being that we care even remotely about would have vanished."

By this he basically means that all emotions would slowly saturate out of an individual and they would no longer have any of the conscious experience that humans currently deem valuable (love, pleasure, happiness etc.). They would become mindless zombies with no real thought or conscious awareness. I think this is a potential threat of allowing the outside control of ones own emotions. When a government becomes the unit of selection as opposed to the individual, there is much less reason for people to have conscious emotions of their own.

Harris also brings up the issue of inequality with the iPlant.

"Inequality: iPlants could create a division in society between the haves and the have-nots. This could become a problem for people who can't afford an iPlant, can't have one for medical reasons, or who simply don't want one. This problem is currently being discussed."

The main problem with inequality is that the wealthy would be able to be considerably happier and have a more refined control of their moods, while the poor would likely have comparatively worse mental health. This is not too different from what currently exists. The poor are more likely to have issues with mental illness and getting the proper treatment for it. The wealthier would also potentially be able to enhance their cognitive functioning to a greater degree to allow the accumulation of even more wealth. So these issues would have to be addressed.

There is also the potential for self-stimulation of the pleasure center which could be a problem.

"Self-stimulation addiction: People might try to bypass the need to perform difficult tasks and self-stimulate ad infinitum. This problem may be avoided by ensuring robust access control by the manufacturer. This problem is currently being discussed."

This is already an issue with a lot of addictive drugs. Some people go on uncontrollable binges of taking rewarding drugs. This brings up the question of who should control the amount of pleasure or reward that a person gets? Is it really possible to ensure that people cannot learn to hijack the implant to enable self stimulation? I think that would be a very difficult task to accomplish as many people would be eager to stimulate their own pleasure center.

Another problem is that increasing a person's pleasure or reward could have negative effects on the individual. An implant will either make currently pleasurable activities more so, or it could make previously non-pleasurable tasks rewarding. Let's say the implant solely makes activities more pleasurable akin to hypomania. People with bipolar mania/hypomania often engage in high risk pleasurable activities to a greater degree that normal people. They may do questionable business transactions, wasteful expenditures of money, and risky sexual activity. Most rewarding activities have a risk to benefit ratio, so there can be consequences when a person engages in those activities too much. Having too much sex for instance increases the risk of contracting a sexually transmitted disease. Being wasteful with your money is also a potential effect of having too much pleasure. Too much pleasure is a negative aspect to bipolar mania/hypomania so there may be an optimal level of pleasure with too much being bad for the individual.

Overall, the iPlant is a very interesting idea. There are many fascinating questions from an individual and societal perspective on this type of technology.

Cortical Brain Stimulation

Northstar neuroscience has created a device that can electrically stimulate the brain. The device that they have crafted is similar to a deep brain stimulation device. A person has to undergo surgery in order to get this device to activate their brain. However, instead of having an electrode implanted deep inside the brain, like with deep brain stimulation, it is implanted on the surface of the brain. This device can continuously electrically stimulate an area on the outer surface of the brain. So they would drill a hole in your head, but wouldn't have to actually punch a hole in your brain to a deeper position. Instead, the device would lie just underneath your skull and on top of your brain. In a study on depressed patients the efficacy appears to be similar in size to transcranial magnetic stimulation when targeted to the left dorsolateral prefrontal cortex. It looks like the improvement in depressive symptoms is fairly modest and a more robust treatment method remains elusive.

"Through the initial eight week comparison period, the Hamilton scores improved 21% for subjects receiving active stimulation compared to 3% for Sham and the Montgomery-Asberg improved 22% versus 8% for Sham."

They have also used this device to attempt to improve stroke symptoms. However the device was not effective for this indication and was not significantly better than the fake treatment.

"To recap the EVEREST, the safety results confirm the positive safety profile that we documented in each of our cortical stimulation studies, however, the primary efficacy end point was not met."

They are also testing the device to improve the symptoms of tinnitus or ringing in a person's ear. As a treatment option I think the utility of this type of stimulation will be limited. In the future, non-invasive brain stimulation is much more likely to be used to improve brain disorders.

Deep Brain Stimulation an Effective Treatment for Depression and OCD

Reuters is reporting that deep brain stimulation DBS has been shown to be an effective treatment for both depression and obsessive compulsive disorder (OCD) in two recent trials. These studies are the largest trials that have been completed using this new technology thus far. DBS involves implanting an electrode inside the brain by doing neurosurgery. The depressed patients in this specific study had very severe depression that was unresponsive to other types of treatments.

"Seventeen patients, diagnosed as having major depressive disorder, were followed for a year and demonstrated overall improvement in mood as well as social and occupational functioning, he said."

"The trial treating OCD included 26 patients who were followed for three years and also showed marked improvement."

Both the depressed and OCD patients improved over the course of treatment with the DBS device. The two clinical trials appear to have had a fairly small number of patients. However, these preliminary results are promising. They confirm the results that researchers have obtained in the past with single patients. A deep brain stimulation device may eventually be used for several disorders of the mind. Researchers just have to run larger trials with more patients before they can get FDA approval.

Deep Brain Stimulation Depression

Deep Brain Stimulation (DBS) involves implanting an small electrode like device into specific areas of the brain. The electrode sends controlled jolts of electricity to the brain and this can improve symptoms for a myriad number of disorders. The area of the brain with the best evidence for mood enhancement using a DBS device is Broadman Area 25. This area of the brain is located in a band that runs deep within the frontal lobes, down the midline. In healthy patients, feelings of profound sadness are associated with increased activation of this brain area. In depression this area shows increased blood flow in comparison to a person without depression and the area is activated for a longer period than in a healthy person. In one such study, 4 out of 6 depressed patients had a striking improvement in their symptoms when the DBS device was implanted in this specific area of the brain. The DBS device can reduce overactivity in that area. So stimulation of this area with a DBS device improves the crushing and despondent sadness that is often associated with major depression.

Currently, scientists are testing in clinical trials an implant device that sends electricity to the medial prefrontal cortex. The medial prefrontal cortex is located behind the bridge of your nose and is important for proper emotional functioning. This area of the brain is involved in attention, interest, emotion and also empathy. A deficit of activity here could concievably cause apathy, poor attention and emotional blunting. So targeted electrical stimulation of this area could lead to an overall improvement in a person's mood. In the future, it may be possible to amplify the experience of empathy so people are more empathatic and warm to each other using a DBS type device. Deficits in empathy are common in several disorders such as autism, asperger's, schizophrenia, anti-social/narcissistic personality disorders and sometimes depression. So a DBS device in this area of the brain might be able to improve those deficits in normal functioning. Interestingly, direct electrical stimulation of the medial prefrontal cortex is rewarding. This is another hedonic hotspot in the brain in comparison to the more well known brain region related to reward (the nucleus accumbens).

The nucleus accumbens has usually been considered the main reward related region in the brain and has been targeted by researchers. DBS devices have been implanted directly within this area of the brain. The nucleus accumbens is mostly involved with feelings of experienced pleasure and doesn't necessarily have a direct effect on many other symptoms of depression such as sad mood. Researchers have found that implanting a DBS device in this area of the brain alleviated refractory anhedonia. However, the other core symptoms of depression such as sad mood we're not changed significantly. DBS devices have been shown to induce euphoria when implanted in this area. So care must be taken by researchers so as not to make person too happy.

Several other areas of the brain have potential antidepressant properties. Scientists have reported on improved mood following a DBS device being implanted into the globus pallidus. The device was actually implanted to treat the movement disorder tardive dyskinesia, but the patient's depression also improved quite a bit. Stimulating the lateral habenula may also have antidepressant properties. Increased activation of the lateral habenular nucleus leads to the down regulation of the serotonergic, noradrenergic, dopaminergic systems and overactivty of the hypothalamic-pituitary-adrenal (HPA) axis. So decreasing activity in this area can decrease the stress response and increase several different mood improving neurotransmitters. Another group of scientists implanted a DBS device into the inferior thalamic peduncle. The researchers found that it had a good effect on the person's depression and that their mood improved progressively over an eight month period. The results for some of these areas are only preliminary. More rigorous clinical trials are needed to discern the true clinical benefit of doing this procedure. However, it could potentially improve the quality of many people's lives in the future.

Flexible Brain Implant Circuit

New Scientist is reporting about a new flexible integrated circuit material that could be used as a perfect "brain wrapper". Most integrated circuit boards are hard and inflexible, but this new one is pliable and can be stretched by up to 15% more than its normal size without breaking. The scientists who created this device have basically taken extremely thin silicon wiring and attached it to a sheet of plastic material. Doing this enables the circuit to be stretched and bent at will, so it would be able to be wrapped around practically any shape. This new circuit may have utility as a brain implant.

The flexibility of this new circuit could let scientists create many different types of brain-computer interfaces in the future. The researchers have said that this technology could be used to monitor brain electrical activity for disorders such as epilepsy. This device could also potentially allow a much more targeted stimulation of the brain when compared to the more crude deep brain stimulation implants currently available. A more flexible brain implant might lead to better treatments for several different brain disorders.

You can watch a video about the material below.

Brain Implant Prosthetic for the Blind

Researchers have proposed a brain impant for the blind, whereby visual signals could be wirelessly beamed directly into the brain. The idea behind this is that a blind person would wear a special pair of glasses that could record video images using two digital cameras. This video would then be wirelessly beamed into an implant that would translate the data into electrical signals to stimulate a specific area of the brain. This area is called the lateral geniculate nucleus (LGN) and is a part of the brain's processing system for sight. By electrically stimulating this part of the brain, it can give a blind person the impression that they are actually seeing something visually. Scientists have already stimulated this area of the brain in primates and found it had induced sight perception.

Doing this procedure would require brain surgery to an area deep inside the brain, which could be somewhat risky. However, scientists have already implanted deep brain stimulation devices inside the brain, and this brain implant would work in a similar manner. The very first devices to be tested will likely be very crude and allow people to see only in very limited detail. However as the technology improves it is possible that scientists would get better at generating sight within the brain that was comparable to a normal person's vision. It is even possible that this technology could be used to enhance a humans vision above and beyond what is normal. The eyesight of a hawk for instance is about 8 times as powerful as human vision. I wouldn't mind being able to have extreme long distance vision, infrared capabilities and increased image resolution for my eyesight. All of these things might in theory be possible in the distant future and could definitely come in handy.

Not only that, but a brain implant could beam in virtual reality images right into your head. This would bypass your vision and would potentially give you a truly immersive virtual reality experience. The science for this specific prosthetic device is still in the preliminary stages, but I wouldn't be surprised to see it tested out in humans in the near future. You can read another good article here on past attempts at creating implantable prosthetics for the blind.

Controlled Study of Deep Brain Stimulation

St. Jude Starting Trial On Brain Stimulation For Depression

"St. Jude Medical Inc. (STJ) has garnered Food and Drug Administration approval to launch a trial the company plans to use to pursue U.S. approval for a pacemaker-like device that uses electricity to treat severe depression."

In depressed patients, a specific area of the brain called the subgenual cingulate region (also known as Brodmann Area 25) shows increased blood flow when compared to non-depressed subjects. For this new study, researchers will use brain surgery to implant a small pacemaker like electrode into this area of the brain. The electrode is expected to improve symptoms of depression by sending controlled jolts of electricity that will reduce overactivity in that specific area of the brain. Researchers have already performed this brain surgery procedure on individual patients in the past but these trials were not controlled. You can watch an older video about DBS for depression here. In one of the first studies of DBS for depression, four out of six patients in the study had fewer symptoms of depression due to the implantation of the electrode in the subgenual cingulate region. In some studies, the change in depressive symptoms for patients undergoing this procedure have been dramatic.

"At his signal, two volts of electricity, enough to power a wristwatch, course through the wires and radiate outward from the tip a few millimeters in every direction. Millions of neurons bask in the electricity, and the effect is fairly immediate. Hire feels warm at first, a bit flushed. And then it happens. The room looks brighter to her. The faces, the big, circular lights overhead, the ceiling-they all seem clearer. Malone asks her how she feels. "I'm really happy," she replies, clearly surprised." Popsci

Researchers have also implanted electrodes within the brain's pleasure center (called the nucleus accumbens) to treat refractory anhedonia. When the electrode was activated in these patients, they suddently wanted to partake in normal activities once again. Depression is often associated with anhedonia, the inability to experience pleasure. Depressed patients often find life unrewarding, which is why many are fairly apathetic. This new trial may finally prove that DBS can ameliorate the symptoms of depression when compared to sham treatment.

Improving Memory by Deep Brain Stimulation

Deep stimulation 'boosts memory'

"Following surgery, the patient recovered for two months. But later when the electrodes were stimulated for a second time, he experienced a similar effect. After three weeks of constant electrical stimulation the patient performed better in memory tests than he had previously done. A year later he again performed well in memory tests when the electrodes were stimulated, but less well when they were switched off. The results suggest it might be possible to use deep brain stimulation directly to boost memory. " BBC News

Deep brain stimulation has previously been shown to have success in treating anhedonia, depression, parkinson's and several other conditions of the brain. You can see a short video of this technology here and a longer video here. This new discovery of memory improvement appears to be a side effect of trying to treat a person's obesity. It seems a little worrisome that they stumbled on this finding accidentally while attempting to improve a condition that was totally unrelated. The good news, though, is that this may become a new treatment option for people with memory disorders, like those who have Alzheimer's disease. I certainly think this is more likely to have a positive effect on patients than the questionable "Alzheimer's hat" that has recently gotten media attention. Though it seems like as a treatment option, deep brain stimulation is always going to be limited in scope because it requires the patient to undergo brain surgery. Brain surgery carries numerous risks and most people would probably pass at the chance of getting it done. However, this new discovery may lead to a better targeting of specific brain areas using deep transcranial magnetic therapy in order to improve memory for alzheimer's patients. Deep tms has the benefit of being non-invasive, so the real world application may be greater.