May 2025

The DBS procedure can appear daunting to a patient! There are 5 crucial steps: The 5 steps of a systematic DBS process 1. Pre-operative evaluation including Levodopa Challenge Test 2. Selection of DBS target and DBS device. 3. DBS surgery itself 4. Post-operative recovery There are five formalities to complete before DBS surgery: There are five formalities to complete before DBS surgery: 1) Ruling out a Parkinson’s Mimic First and foremost, the diagnosis of Parkinson’s disease needs to be confirmed. The doctor will carefully talk to you and examine you. His/her main intention is to rule out a Parkinson’s Disease Mimic. A Parkinson’s Mimic is any disease that looks like Parkinson’s disease but is not. Parkinson’s Mimics include the Parkinson’s Plus syndromes. Your neurologist will look for these “Red-Flag” symptoms, which may indicate that you have a Parkinson’s Plus syndrome. Red flag: Your doctor will be extra careful if you have any of the following symptoms. ‘Red Flags’ suggesting that you may have a Parkinson’s Plus Syndrome 1. Lack of response to Levodopa. 2. Frequently falling, especially backwards. 3. Severe talking or swallowing problems. 4. Problems with eye movement. 5. Impotence. 6. Blurring of vision. 7. Blacking out when rising from a seated position. 8. Problems with thinking or memory loss. 9. Personality changes. 10. Symptoms only in the legs while the arms and hands are entirely normal. 11. Rapid progression of the disease. Click here to read more about Parkinson’s Mimics. Click here to read more about Parkinson’s Plus syndromes. A careful history and examination are critical. Also, a small therapeutic experiment is done. This experiment is the Levodopa Challenge Test. 2) Levodopa Challenge Test Most people with Parkinson’s Disease never stop responding to Levodopa. But the effect of Levodopa becomes shorter and shorter as the disease progresses, and sometimes it may cause side-effects. So, the reason for doing DBS is motor fluctuations, which are described here. Let us say a person who is going to have DBS takes a large quantity of Levodopa. This is called the “Levodopa Challenge Test”. What would you guess happens immediately afterwards? Here is the key: The person should improve, even at this stage. Significantly. A good Levodopa Challenge Test: Excellent improvement (>30%) after taking levodopa predicts that DBS will be successful. No one would expect this improvement to last the entire day – that is the reason that DBS is being done in the first place. But at least for an hour or so, the person should improve. Significantly. In fact, the maximal improvement that you get during the Levodopa Challenge Test is likely to be the maximal improvement after DBS. If a person fails to improve dramatically, then it predicts that DBS may not work. As with all things in life, this prediction is not absolute. How is the test done? You will be asked to stop taking your Parkinson’s medications after your night-time dose / at least for 12 hours. Most places will ask you to stop eating after dinner. You can keep drinking water as usual. You will be requested to come to the hospital in the early morning. There, the Neurologist will carefully examine you and give you a score for motor functioning. He/She will use a very lengthy scale called the UPDRS-scoring system. The UPDRS is a very complicated scoring system that measures your performance. Then, you will be given a sizeable dose of Levodopa, for example, 4 tablets. This dose is usually slightly higher than the dose you are currently taking. Many authorities recommend that 150% of your morning dose should be used. Doctors may use up to 200% of your morning dose if you fail the test once. The Neurologist will again reexamine you 30 minutes, 1 hour and if needed 1.5 hours after taking the Levodopa tablets. What is “Significant Improvement”? This measurement cannot be subjective. What may seem significant to your doctor may not seem significant to you. To avoid such ambiguity, we use the UPDRS to quantify your symptoms. The minimum improvement required to predict a good DBS response is known. If at any point after taking the challenge dose, your UPDRS score improves by 30% or more, then you are likely to improve after DBS. This is a single page of the UPDRS scoring sheet. You can access the complete scoring sheet by clicking on the picture. If I fail the Levodopa Challenge Test, can I still get DBS? Some people can. If you do not improve, the reason for non-improvement should be found. If you failed the Levodopa Challenge Test because of specific reasons, you could still have DBS. Reason for Levodopa Challenge Test Failure Resolution The dose of Levodopa used was not large enough May need to re-do test with a larger dose. You cannot tolerate a large dose – you get too nauseous. May need to take tablets for nausea so that a large enough dose can be given. You start shaking too much after a large dose (these are called dyskinesias). So, your post-challenge scores are low. May need to proceed with DBS without the assurance provided by the Levodopa Challenge Test. Your gut did not absorb the Levodopa. For example, you ate a heavy breakfast by mistake or were constipated. May need to repeat the test with proper precautions. You failed the test because your Tremor did not improve after the Levodopa dose. May proceed, but discuss with your doctor adequately. Tremor may respond to DBS even if it does not improve with the levodopa challenge. You failed the test because the stiffness of your body, walking or unsteadiness did not improve after the levodopa challenge. Be very careful. These symptoms may not improve after DBS either. You have a Parkinson’s Mimic, possibly a Parkinson’s Plus Syndrome. DBS is not a good option, at present. But you may want to participate in a carefully designed, ethical research trial of DBS in these conditions. Here is one being conducted by Harvard. So, some patients may fail the Levodopa Challenge Test but may still respond well to DBS. You can read a useful review of such patients here. [External Link: Morishita

Which is the best DBS device? Actually, no DBS device has been proven to the best. All DBS devices are very good. Newer devices provide many additional features. But whether these additional features help patients in the real world is not known. Let us learn about these issues. Which companies manufacture Deep Brain Stimulation (DBS) systems? Earlier, only Medtronic made a Deep Brain Stimulation (DBS) system. Their device is called “Activa”. The Medtronic-Activa system has 3 varieties. PC – non-rechargeable. RC-Rechargeable & SC – single channel for one-sided stimulation only. Subsequently, two more devices were approved: Abbott – The device is called “Infinity”. Boston Scientific – The device is called “Vercise”. Is Abbott’s “Infinity” the best DBS device? There are 2 varieties of the system. The Abbott system has 2 varieties. The larger one (Infinity-7) is for the usual stimulation (both sides of the brain). The smaller one (Infinity-5) can only do one-sided stimulation. There are 2 additional advantages:Small size: The single-channel device (Infinity-5) is the smallest DBS battery available. But, that is not the most crucial feature of the Infinity system.More stimulation points: In the Infinity system, you can select a wire with more stimulation points at the end (up to 8). So, you can give stimulation precisely – to only a small brain part.Current steering: The Infinity DBS system can “steer” the electrical current. It can point the electrical current in a particular direction. So if you want only the right side of the wire to get current, you can do that. Current to the left – you got it! Here is a video of how this is done. This video mentions the Vercise device (described below), which has similar features: https://www.youtube.com/watch?v=nVLWauTKfPo How can “steering” current help? This ability is useful when the end of the wire is not exactly in the target. For example, let us say the target is slightly to the left of the wire. Then, the Infinity device can make the current go more to the left. It may also help to reduce side-effects. For example, let us say stimulation is causing hoarseness of voice. The Infinity system can steer current away from the part whose stimulation is causing hoarseness. So, in theory, this ability should improve movement while at the same time reducing side-effects. Is Boston Scientific’s “Vercise” the best DBS device? There are 2 varieties of the system. Abbot’s Vercise System – The Gevia is rechargeable. The PC model is not rechargeable. There are 4 advantages:Longevity: There are two varieties of the Vercise system – rechargeable and non-rechargeable. The rechargeable Vercise system holds a trump card. You don’t need to replace the battery for a long time! (see below) Vercise-Gevia is the energizer bunny of DBS-systems. It also has all the other technical features of other systems. More stimulation points: Same as the Infinity system.Current steering: Earlier, the Vercise system was not capable of “steering” current. In 2019, a newer version of the device (specifically, a newer wire called Cartesia) was approved. This more recent version is capable of steering current. Are the more expensive Infinity / Vercise DBS devices really better than the older, cheaper Activa DBS device? No one has done a head-to-head study comparing these devices. Therefore, we don’t know if one of these devices is better than all others – the “best DBS device”. My take on it is this: FOR GPi-DBS: Medtronic-Activia is the only approved choice. As noted before, at present, the Infinity & Vercise systems are not approved for GPi-DBS. For STN DBS: Both the newer devices are, in general, more expensive than the Medtronic device. The crucial technical difference is “Current Steering”. The other variables: size & longevity, are usually less important. ” IF the neurosurgeon places the end of the wire perfectly inside the STN, THEN the effect of all devices should be similar. “ Putting the wire perfectly into the STN is not easy. As noted in a previous article, they are like two little peas in the centre of the head. Neurosurgeons do a phenomenal, near-superhuman task by doing it perfectly most of the time. But sometimes, the lead may be a few millimetres off-target. Neurosurgeons hit the STN with near-superhuman skill. But they are not infallible. Using the Vercise/Infinity devices is planning for a contingency, which rarely arises. If you are monetarily able to do so, you could arrange for this rare contingency. Which is the best device for DBS? Both the newer devices are, in general, more expensive than the Medtronic device. The newer devices are attractive in principle. But, they have not been proven to be more effective than the Medtronic device. For GPi-DBS, the only choice is Medtronic-Activa system. For STN-DBS, any of these devices is an excellent choice. For STN-DBS, the doctor usually chooses the device he/she is most comfortable with. Sometimes, choosing is difficult because the differences are minor. Reference / Further reading: Here is an excellent article about DBS device selection: Okun et al. 2019 – Tips for choosing a DBS device – JAMA Neurology Here is a phenomenal, but very technical, article comparing all DBS devices: Paff et al. 2020 – Update on current technologies for DBS in Parkinson’s disease – Journal of Movement Disorders. How many years does the battery of Deep Brain Stimulation (DBS) last? The best DBS device would have a never-ending battery. But, in real-life the DBS battery does run out after some years. Each of these devices has two varieties: Non-rechargeable & Rechargeable. The non-rechargeable batteries are cheaper. However, they last for a shorter period. When the battery runs out, the wires inside the head do not need to be replaced. Only the battery below the chest skin is replaced. So, the battery replacement surgery is much simpler and quicker than the original surgery. The estimated average life of each of these batteries is noted below. Non-Rechargeable DBS   Model Number Average life span (years) Medtronic Activa Activa – PC 3 to 5 Abbott Infinity Infinity 5 & 7 4 to 5 Boston Scientific

STN-DBS versus GPI-DBS – Which DBS location is better? Worldwide, the most common DBS location is a brain part called the Subthalamic Nucleus (STN-DBS). So, most doctors think it is better. But in some patients, an alternative location may be better. This alternative location is the Globus Pallidus Interna (GPi). In fact, some doctors think that GPi-DBS is better in all cases! Your doctor will do this thinking for you. He/She will tell you the proposed location. But, its good to know how he/she thinks! Let us learn quickly about the pros & cons of these locations. What do you mean by DBS-Location? DBS passes a small electrical current into a small brain part. The small brain part is called the DBS location. Many doctors will call it the DBS Target instead. Look at the picture below. The end of the DBS wire marks the location. The DBS location will get a small current from the Battery. Usually, there are two wires, one on the left and one on the right. See the wire going into the brain? The location where it ends is the location that will get the current. That is the “DBS location” (or “DBS Target”) You could use any location in the brain. But doctors have found two great locations already. The names of these two locations are: Subthalamic Nucleus (STN) Globus Pallidus Interna (GPi) Subthalamic Nucleus (STN-DBS) Where is the Subthalamic Nucleus (STN)? The STN is deep, very deep, inside the brain. There is one two STNs. One on the left, and one on the right. They are also tiny. Like peas. Ok, so close your eyes, and imagine. Two peas, almost touching each other, in the centre of your head, just below your ears. The 2 STNs are like two small peas, in the center of the head. That’s it! That is where the two STNs are. What is the benefit of STN-DBS? Let us say your doctor puts the end of the wire into the STN. And switches on the small current. What happens? STN-DBS decreases the symptoms of Parkinson’s disease. You need less levodopa after STN-DBS. Usually, the levodopa dose can be gradually reduced by 1/2. STN-DBS also keeps acting throughout the day, so it decreases “Predictable-OFFs”. A simple example: Let us talk about an imaginary person – Mr. Salisbury. Mr. Salisbury is already taking 12 tablets of levodopa. He takes 3 tablets every 4 hours. A few minutes after he takes this high dose, he gets nauseous and sometimes starts shaking too much. But he insists “But I absolutely need this dose to function!” Mr. Salisbury needs a high dose of levodopa to function. But every dose makes him shake a lot. And every dose only works for 2 hours. “I know these are Dyskinesias” he says. “But I put up with them because I need that high dose of levodopa to function!“. That is not all. Just 2 hours after taking the levodopa, it’s effect wears off. Mr. Salisbury goes into the OFF-state again. He almost completely freezes. This wearing-Off is very predictable. After STN-DBS, Mr. Salisbury becomes ON with only 1.5 tablets of Levodopa. Not only that, the effect now lasts for 4 hours. Even when he goes into the OFF-state, he is not completely OFF. He does not completely freeze. Mr. Salisbury is particularly happy that his levodopa dose has decreased. Because his dose has decreased, he has less severe dyskinesias. After STN-DBS, you may need only 50% of your current levodopa dose. In summary: STN-DBS decreases both Predictable-OFF & Dyskinesias. But, the effect on dyskinesias is indirect. What are the side-effects of STN-DBS? STN-DBS causes two characteristic side-effects. Increasing severe depression, if you already have it. Increasing memory problems, if you already have them. If you are dramatically depressed or have severe memory problems, perhaps STN would not be the right DBS location for you. STN-DBS may rarely cause depression or memory problems. But this is rare. Mostly, all it does is to increase severe problems, if you already have them. So, if you already have these very severe problems, STN-DBS may not be the right choice. What can you choose instead of the usual STN-DBS? If you have these problems, and they are severe, you should probably not choose usual DBS. You can choose: Not to have DBS or STN-DBS of only one side or DBS of another target called the Globus Pallidus Interna (GPi) If depression or memory problems are extremely dramatic, then not having DBS may be considered. For borderline problems, many doctors consider another target – the GPi. This is called GPi-DBS. Globus Pallidus Interna (GPi-DBS) Where is the Globus Pallidus Interna (GPi)? The GPi is not as deeply located as the STN. There are two GPis. One on the left, and one on the right. The GPis are bigger. They are shaped like this yo-yo here. Imagine a small yo-yo like this, inside your head, just above your ears. The two GPi look somewhat like a Yo-Yo. They are larger than the STN. That’s it! That’s where the two GPi are. What is the benefit of GPi-DBS? Overall, GPi-DBS causes the same benefits as STN-DBS. But, the way it does so is different. GPi-DBS decreases the side-effects of levodopa, especially DYSKINESIA. Let’s consider an imaginary person, Ms. Mary. Ms. Mary is not able to take enough levodopa to decrease his symptoms. She can only take 4 tablets in a day. Why? Because when she takes more tablets, the body starts shaking too much. Like the video below, posted by a brave patient on youtube. These movements are called “Dyskinesia”. “I really wish I could take more medication!” says Mary. “But if I try to increase it, this dyskinesia just becomes intolerable!” https://www.youtube.com/watch?v=AaOWRYqMQc0 Wouldn’t it be wonderful if these bad movements went away? GPi-DBS does that. After GPi-DBS, Ms. Mary can take 8 tablets per day without any side-effects. Her Parkinson’s symptoms are much better. After levodopa is increased, will GPi-DBS benefit Mary as much as

Allow me to give you the Patient Criteria for a good DBS candidate upfront. You are the ideal DBS candidate if you fulfil all the following: Go Ahead with DBS Stop & re-consider 1. Your life is significantly hampered, despite taking proper medications 2. If the diagnosis of Parkinson’s disease is sure, and there are no “red flags.” 3. You improve markedly with the “Levodopa Challenge test”. 4. You clearly understand the risks & success rates, and have realistic expectations 1. If you have other serious medical problems which would make surgery risky. 2. If you are uncontrollably depressed. 3. If you have severe thinking & memory problems. Please try to understand this table entirely before you get DBS surgery done. I will try to explain it to you, in the simplest possible terms. Let us start. Who is a good DBS candidate? Please note that here, we will talk only about DBS for Parkinson’s. DBS is used for other problems as well – including epilepsy. We will not talk about those conditions in this article. DBS can result in good improvement in some Parkinson’s Patients. Videos such as the one below are genuine and very encouraging. This video has been posted on Youtube by the Neuromedical Center in the USA. https://www.youtube.com/watch?v=wZZ4Vf3HinA All patients may not get the same benefit. So, proper selection of: The patient The location of stimulation The device with which stimulation is done is very important. Here we will talk about patient selection. The other topics are covered later. Here is the first question to answer: What is the reason you want to consider DBS? There is only one reason to consider DBS. You should consider DBS if – despite taking medications – your life is hampered by Parkinson’s Disease. We call this “Disability”. You know, even late-stage Parkinson’s patients improve after a single big dose of Levodopa! So why are patient’s activities hampered? They are hampered because of motor fluctuations. Let us look at the 2 most common fluctuations: 1. Predictable Wearing-OFF: You might feel almost perfect after taking Levodopa. But the effect wears-off too soon. It may wear off after 2 hours, or sometimes even after 1 hour. You can literally predict what is going to happen. Then you take another dose, and you’re fine. But then within 1-2 hours, the same thing happens again! Here is a video posted by Orion Pharma. A patient called Ms. Doreen describes her wearing-off symptoms: https://www.youtube.com/watch?v=5EjbX-x51r0 This “Wearing-Off” problem is probably the most common reason for DBS surgeries. 2. Dose-Limiting Dyskinesias: Initially, you took small doses of Levodopa. As the years went by, you needed larger doses. Fine. You still improved But some people notice that when they take larger doses, their body starts shaking. For lack of a better description – these excessive movements look like slow break-dancing. These are called “dyskinesias”. They can be quite severe. Here is a video of Dyskinesias caused by Levodopa. This video has been posted by a brave patient named Ms. Tessie on youtube. https://www.youtube.com/watch?v=AaOWRYqMQc0 So, some people are in a quandary. Don’t take enough Levodopa, and they become stiff. Take enough Levodopa, and get dyskinesias. These patients cannot take as much Levodopa as they need because of severe “dyskinesias”. The way out is DBS. STN-DBS makes you function even with a 50% levodopa dose. GPi-DBS is excellent in another way: You can read more here [STN versus GPi DBS]. There is a good reason. What next? There are two essential goals of DBS surgery for Parkinson’s Disease: To improve the patient’s functioning. To avoid side-effects Let us look at each one of these: How can doctors predict if you will improve after DBS? At present, we are not able to use DBS for Parkinson’s Plus Syndromes. PSP & other Parkinson’s plus syndromes do not improve after regular DBS. So, a patient with a “Parkinson’s Plus Syndrome” is not a good candidate for DBS. At least, at present. In the future, a modified DBS procedure may be useful in Parkinson’s Plus Syndromes. But at present, a major task before DBS is to confirm Parkinson’s disease and rule out other conditions. If you really have Parkinson’s disease (and not a Parkinson’s Mimic), then there is an excellent chance of improvement after DBS. How are other diagnoses ruled out? Parkinson’s Plus Syndromes are diagnosed by talking and examining you. Doctors call this a “clinical diagnosis”. The presence of some symptoms may warn you that you have a “Parkinson’s Plus Syndrome”. Doctors call these symptoms “Red Flags”. Here is a list of such red flags: Red flags – you may have a “Parkinson’s Plus” syndrome instead Lack of response to Levodopa. Frequently falling down, especially backwards. Severe talking or swallowing problems. Problems with eye movement. Impotence. Blurring of vision. Blacking out when rising from a seated position. Problems with thinking or memory loss. Personality changes. Symptoms only in the legs while the arms and hands are entirely normal. Rapid progression of the disease. When in doubt, blood tests, MRI or FDOPA scan may help to rule out other conditions. You can read more here [Conditions that look like Parkinson’s]. Levodopa Challenge Test: Let’s say your doctor is sure that you have Parkinson’s disease. What else does he/she do to predict DBS response accurately? He/She give you a single big dose of Levodopa. This is called a “Levodopa Challenge”. Doctors have discovered that the improvement after a large dose of Levodopa predicts improvement after DBS. If you improve rapidly after a big dose of Levodopa, you will likely respond to DBS. Your doctor will decide how many tablets to use for testing. Let us say you markedly improve after the big levodopa dose. That’s great! This indicates that you will improve after DBS. You are a good candidate for DBS. If you do not improve markedly after a big levodopa dose, you may still be a DBS candidate. But you will need to discuss the reasons why the challenge test failed, and the pros & cons

DBS is the short form of “Deep Brain Stimulation”. DBS is one type of Parkinson’s Surgery. DBS works by passing a small current into the brain. This current is passed into only to a small part of the brain. The doctor selects one out of two brain parts (either the GPi or the STN). DBS works by changing the electrical currents in these areas. At present, we cannot mathematically calculate these changes. But, empirically (as-seen-with-our-own-eyes) – DBS improves Parkinson’s symptoms. Let us learn more about these topics: What is Deep Brain Stimulation for Parkinson’s disease? DBS is electrical stimulation of the brain by using a small machine. DBS can stimulate many brain areas. DBS is actually approved for many diseases. It is not just a “Parkinson’s surgery”. It can be used for epilepsy and other movement disorders as well. The basic setup is the same. The DBS battery is inserted below the chest skin. Two small wires from the battery go up to the head. The wires go through the skull. They are inserted into the desired area of the brain. A DBS system – The battery/pacemaker is placed below the skin in the chest. The wire going inside the brain is called an “electrode” For Parkinson’s disease: This target area of the brain is usually the “Subthalamic Nucleus (STN). In some patients, another area is chosen as the target. This other area is the Globus Pallidus interna (GPi). How is the target chosen? Read this article [Click here] DBS can dramatically improve Parkinson’s symptoms. There are many before-after videos available on the internet. For example, here is a video posted on youtube by the Neuromedical Center in USA. https://www.youtube.com/watch?v=wZZ4Vf3HinA How does Deep Brain Stimulation (DBS) work? No one completely understands how Deep Brain Stimulation (DBS) works. Doctors used to cut small parts of the brain to reduce Parkinson’s symptoms. This surgery is called a “tomy”, meaning “to cut”. For example, Thalamo-tomy, Pallido-tomy. A small electrical current is used to stop small bleeds during surgery. This is called “electrical cautery”. While doing this current, they noticed something odd. When they passed a current into certain brain parts, the Parkinson’s tremor disappeared! Would it be possible to continue the stimulation indefinitely? This question led to the design of the DBS electrical system around 2000. DBS was approved for widespread use in 2002. Reference: 1. “History & Future of Deep Brain Stimulation” Schwalb 2008: Fascinating article on how Deep Brain Stimulation for Parkinson’s was discovered (lots of pictures, free to read) DBS was invented by very, very smart and dedicated people. Ah Yes! So, it is one of those things where we don’t know how it works. But years of experience have shown us that it does. Like, complimenting your spouse… Many researchers believe DBS stimulates the target. Some believe DBS actually causes the target to stop working. The reality is complex, and as yet, out of reach. Each of these targets (for example the STN) contain many millions of little cells arranged in very intricate circuits. The circuits in each part of the brain are very complex. We don’t understand how they are affected by DBS. Probably, the DBS current stimulates some of these cells, while other cells stop working. Some circuits go into overdrive, while others shut down. This varying effect also varies according to the current characteristics, especially frequency. The net effect is, at present, impossible to calculate mathematically. Empirically though (with our own eyes), we see that when the stimulation is given at a high frequency – Parkinson’s symptoms decrease markedly. What is the best theory for why DBS works? Before starting, let me note that reading this part is not critical. It is very technical. As noted before, we don’t really understand how DBS works. But there are numerous complicated theories. Let us look at the simplest & most promising one, in relation to DBS of the most common target. The most common target is the Subthalamic Nucleus (STN). First, let’s see what causes Parkinson’s disease. Usually, Dopamine keeps the STN in check. When Dopamine decreases, the STN runs amok (becomes hyperactive). This causes problems with movement – especially slowness. We recognize these as “Parkinson’s disease”. STN: Without dopamine keep it under control, that pink little thing runs amok. What happens when you put a wire into the STN and pass a high-frequency current through it? If you pass high-frequency electrical current into the STN, it cannot keep doing what it is doing. The fast electrical buzz causes it to go into “overload”. The part being stimulated (e.g. the STN) stops working. Gatekeepers in the brain (e.g. a part called the Thalamus) prevent the high-frequency electrical current from spreading to the rest of the brain. Thus, the rest of the brain keeps functioning well. The other theories are a variation on this theme. Click here for a short table about these proposed mechanisms. Some DBS effects cannot be explained by this theory. Many symptoms including tremor and slowness decrease with high-frequency stimulation. But some symptoms like Freezing decrease with low-frequency electrical stimulation. Why? We don’t know. Therefore, there is a lot more to discover. If the mechanism of DBS is not known, why should I consider it!? Because it works. Because it is quite safe. There are many things for which we don’t understand the exact reason. For example, we are still finding out more about the myriad benefits of exercise. For example – How does exercise improve Mood? We don’t understand that too well. But it is easy to grasp that exercise is good for you. This what-you-see-is-true evidence is called “Empiric Evidence”. Exercise, even in short bursts, has tremendous benefits. We don’t mathematically understand the mechanism behind all these benefits. So, Should I get DBS surgery for Parkinson’s? “How does DBS work?” is a good question. “Should I get DBS?” is a separate question. The success rate of DBS is quite high. If the patient is properly selected, most of them benefit from it. You can read

Normal functioning of the brain Our brain is divided up into many different parts. These different brain parts have varied functions. For example: The brain parts in the front do most of the thinking. The brain parts behind the ears store memories. The brain parts just above the ears help us to move our hands and legs. The brain parts at the very back help us to see things. And so on… These parts communicate with each other using minute electrical currents. This electricity is strictly regulated. Our hand only moves when we want it to move. We remember something only when it is relevant, or we try to remember it. We see something only when our eyes send a electrical current to the brain parts in the back. Thus, usually these things happen for a reason. Patients with seizures can get olfactory (smell) hallucinations. What causes a seizure? A seizure is caused by a sudden uncontrolled surge of electricity in the brain. If wires connecting two brain parts are not properly connected, electricity in that area can become un-regulated. This may occasionally cause cause a sudden surges of electricity. Frequently, this electrical surge is suppressed by our brain. But sometimes, this local electrical surge becomes uncontrollable. It may spread to other areas of the brain, like an electrical storm. A seizure is like an electrical storm inside our head. When the electrical storm involves different brain parts, you experience symptoms related to that brain part. For example: If the electrical surge involves the brain part behind the ears, you may get a sudden surge of memories. If it involves the brain part above the ears, your hand may cramp up or start shaking If it involves the back of the brain, you may see things and so on… If the electrical storm spreads over the entire brain, your entire body shakes violently and you lose consciousness. At this stage, the electrical storm is called a “Generalized convulsion” or “Generalized Tonic-Clonic seizure”. When the electrical storm spreads over the entire brain, the entire body may start shaking. What happens during a seizure? The symptoms during a seizure depend on which brain part is involved. A few examples are given above. Our brain produces ALL our experiences. Therefore, you can get any kind of experience during a seizure. But some parts of the brain have seizures more frequently than others. Therefore, some symptoms are more common during seizures. Each part of our brain has a specific, unique function. Common symptoms which happen during a seizure A bad odor. It may be disgusting (for example of garbage) or sickeningly sweet. A bad taste. A metallic taste, or a bitter taste is very common. Some patients report tasting blood. Extreme fear or anxiety. A Deja-Vu feeling: An intense feeling of “This has happened to me before”. Difficulty in talking or understanding other people. Visual hallucinations: Seeing things that are not really in front of you. Tingling or numbness in the face, arm or legs Cramping or shaking of a hand, leg or the entire body. Involuntarily passing urine or stool. Blanking out and staring off into space As noted, any experience can happen with a seizure. Here are some experiences/symptoms that occur with seizures, but less commonly. Less common symptoms during a seizure Extreme anger Extreme happiness or sadness A feeling of floating away from your body and looking towards it from above (Autoscopy) A feeling of being one with nature, or with the surroundings (Depersonalization) Sudden nausea or urge to vomit Sudden urge to urinate Dizziness Hearing strange sounds such as ringing bells or people talking Repetitive eye blinking In addition to these symptoms that happen during a seizure, there may be some complications due to a seizure: You may bite your tongue. In generalized convulsions (see above), some people may dislocate their shoulder. In generalized convulsions,  some people may get other injuries – such as bruises or head injuries. After a seizure, you may have trouble speaking, using a body part or thinking for some time. You may bite your tongue during a seizure. Warning signs of a seizure (Aura) An Aura is the beginning of a seizure. Many patients interpret this as a warning sign of a seizure. Auras are usually seen with Focal seizures (see below) When the seizure is small, it produces minimal symptoms. It may produce a bad smell, or some memories, or some problems with eyesight. Later, when the seizure spreads over the entire brain, the patient gets a big seizure. For example, a patient may smell something bad, and then get a large seizure with violent shaking of the entire body. An aura is a small seizure that produces subtle symptoms. When this keeps happening repeatedly the patient recognizes that the bad smell is a warning. This warning is called an “Aura”. Auras in Primary Generalized Seizures: Primary generalized seizures (see below) usually don’t produce an aura. The occur without warning. This is because they occur over the entire brain at once. However, newer research has show that even in these kind of seizures, some patients get a warning. This warning is felt before the big seizure. How this happens is not known. Auras also occur in primary generalized seizures, but they may be difficut to describe. Types of seizures There are two main types of seizures. Focal seizures and Primary Generalized seizures. Focal seizures: Partial seizures start in one part of the brain’s surface. Sometimes, a focal seizure may not spread and produce limited symptoms. At other times,  it may then spread to the entire brain and produce dramatic symptoms. Generalized seizures & Focal seizuresPrimary Generalized seizures: Generalized seizures start all over the brain, at once. It is unclear where they start from. Many researchers believe that they start deep within the brain. These deep-seated brain parts are called the “Basal-Ganglia” & “Thalamus”. These seizures had different names earlier. For example, focal seizures used to be called “Partial seizures”. Even more confusingly, each one of

The meaning of the medical term Bradykinesia is “slowness of movement”. He/she has Bradykinesia means that the person walks, talks, eats and even blinks slowly (see video below). If a person does not move at all, it is called “Akinesia”. The most common cause of Bradykinesia (meaning slowness of movement) & Akinesia is Parkinson’s disease. Doctors test for bradykinesia by asking the patient to do various tasks. These tests include tapping fingers rapidly. The treatment for bradykinesia depends on the cause. A medication called levodopa can reduce bradykinesia in Parkinson’s disease. Hello! I am Dr Siddharth Kharkar, a Neurologist in Thane, India and a Neurologist in Mumbai, India. I provide Parkinson’s treatment in India and am an Epilepsy specialist in India. I provide Epilepsy surgery in India at Mumbai & Parkinson’s surgery in India. Let us know more: Bradykinesia Meaning & difference between bradykinesia, Hypokinesia & Akinesia These words are from the Greek language. Bradykinesia: Brady means slow. Kinesia means movement. So Bradykinesia means “slow movements”. Here is a video of  a bradykinetic patient, being examined by Dr. Niall Turbidy from the University of Dublin. Most importantly, notice how the lady’s is walking slower than usual. This is called Bradykinesia. https://www.youtube.com/watch?v=kXMydlXQYpY&t=16sHypokinesia: Hypo means little or reduced. When a patient does not move much, he/she is said to have hypokinesia. Akinesia: A means absent. Akinesia means loss of some or all movements. For example, loss of blinking or normal arm swinging while walking. Bradykinesia, Hypokinesia and Akinesia have slightly different meanings. But since they are similar, many doctors use only one word in their note. The most popular word is “Bradykinesia”. So when doctors write the word Bradykinesia (meaning simply “slowness of movement”), they indicate that the patient has all 3 symptoms described above. Some doctors may prefer to write “Akinesia” or “Akinetic syndrome” instead. Reference / Extra reading: 1. Marsden’s textbook of Movement disordersThis is the “bible” of movement disorder specialists. Although possibly too complex for individual patients, Chapter 3 and Section 3 in the book beautifully describe the terms discussed here. 2. The terminology of Akinesia, Bradykinesia & Hypokinesia – Schidler 2017 This paper describes how the meaning and usage of these terms has evolved. A fascinating read, but very detailed. Bradykinesia versus Dyskinesia Even though they sound similar, bradykinesia and dyskinesia have very different meanings. Dys means “bad”. Dyskinesia means excessive “bad” movements. Usually, these bad movements are jerky dance-like movements of the limbs. Treatment with certain medications like levodopa can cause Dyskinesias of the limbs. Some psychiatric medications can cause excessive facial movements, called “Tardive dyskinesia”. What does bradykinesia feel like? You may have the following symptoms of Bradykinesia. You may yourself notice these Bradykinesia symptoms. Sometimes, it is your friends who might bring your slowness of movement to your attention. In the morning, when you are trying to stand up from the bed and walk, your feel might feel stuck to the ground. It may take longer to take a bath and get dressed. Doing fine tasks like buttoning of shirts and writing may be difficult. Doing any movement may need you to make an extra mental effort. You may get left behind when walking in a group. Your spouse may complain of you taking too long to get ready. Patients with Parkinson’s disease can get “left behind” when walking in a group, because they walk slowly. It is easy to attribute bradykinesia to ageing. This is a mistake. Early evaluation by a doctor is critical. A doctor can confirm bradykinesia, and treat it in time. How do doctors test for bradykinesia? Tests for bradykinesia do not need special instruments. The doctor will ask you to perform certain tasks. Some of these are: Some doctors may prefer to write “Akinesia” or “Akinetic syndrome” instead. Tests for Bradykinesia Tapping your fingers together as fast as you can Opening and closing your fist rapidly Turning your palm up and down – like flipping a pancake – as fast as you can Tapping your toes or heel on the floor – as fast as you can During this time, the doctor notices: How long it takes for you get started How fast you are able to do the movement Whether the movements become smaller after a few seconds…. and so on…. Here is an excellent video of Dr. Kathleen Poston from Stanford University demonstrating the tests done for bradykinesia. https://www.youtube.com/watch?v=cxHpFWKIfGw&t=100s If you take a long time to start moving, the doctor may suspect Akinesia. If you have slow movements, the doctor may suspect bradykinesia…. As noted before, your doctor may write a single phrase (for example “akinetic syndrome”) to describe all these symptoms. Reference / Extra reading: 1. Neupsykey – Approach to the hypokinetic patient.A detailed description of what doctors check in a hypokinetic/bradykinetic patient. I think, now we know the answer to the question: What is Bradykinesia? Let us look to an even more important question: What causes Bradykinesia? What are the 8 causes of bradykinesia? Parkinson’s disease is the most common cause of Bradykinesia. Bradykinesia meaning simply, slowness of movement, may also be due to other causes. Some patients who walk slowly may not have “true”-bradykinesia at all! They may be walking slowly because they are afraid of falling down. This “cautious gait” is due to a problem in the balance system of the body. Thus, it is very important for the doctor to confirm that you have “true”-bradykinesia. Even if you do have truly slow movements, you may not have Parkinson’s disease. There are 4 main features of Parkinson’s disease. Most patients with Parkinson’s disease will have two or more of these symptoms: 4 Cardinal signs of Parkinson’s disease Slowness (Bradykinesia, Hypokinesia or Akinesia) Uncontrolled shaking (tremor) Stiffness (rigidity) Unsteadiness Other than these 4 symptoms, patents with Parkinson’s disease have other symptoms too. There are many problems with movement in Parkinson’s disease. If your only symptom is slowing of movements, you may have another disease. Here are the 8 causes of Bradykinesia 8 Causes of Bradykinesia (meaning slow movements) Parkinson’s disease and Parkinson’s Mimics Hypothyroidism Severe depression Damage to the front of your brain,