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PsychEd+episode+20+-+Understanding+rTMS+with+Dr.+Jonathan+Downar.mp3
Christina: [00:00:02] Perfect. So have a seat. We're going to do something called Automotive threshold on you today, which is basically we're going to be using the magnet on your head to see at which amplitude your arm. So it's uncomfortable. I won't say it's painful. We're going to be using about 0.2 pulses per second. So 3 to 1.
Alex Raben: [00:00:57] Welcome to PsychEd, the Psychiatry podcast for Medical Learners, by Medical Learners. Today's episode is on rTMS. Repetitive transcranial magnetic Stimulation, rTMS is a type of neurostimulation therapy for the treatment of depression. It falls in the same category as ECT or electroconvulsive therapy. And although it's not as well known as ECT, rTMS has steadily become an important option in the treatment of depression, which is why we've decided to focus on it. In today's episode, Henry Barron had a chance to sit down with Dr. Jonathan Downer, a world expert and leading researcher on rTMS, and his clinical fellow, Dr. Jean-Philippe Miron. Not only that, Henry also recorded himself experiencing some non therapeutic levels of rTMS. To give you some idea of how treatment feels from our patients perspectives, let's go over the learning objectives. By the end of the episode, we hope that you'll be able to, number one, understand generally how rTMS is conducted and some of the theory behind how it works. Number two, understand where rTMS fits in the treatment algorithm for depression. And number three, appreciate the benefits, side effects and drawbacks of our rTMS and how it compares to other depression treatments. So without further ado, let's jump in.
Henry Barron: [00:02:24] All right. So why don't we start with introductions? So I'm Henry. I've been behind the scenes doing some audio editing, and it's a great privilege today to be here with Dr. Jonathan Downer. Maybe if you could introduce yourself.
Dr. Jonathan Downar: [00:02:38] Sure. Absolutely. So my role here is as a clinician scientist with the Department of Psychiatry at the University of Toronto and the director of the rTMS Clinic here at the Toronto Western Hospital. By way of background, so my Ph.D. 20 years ago was in functional MRI of a network that turned out to be the Salience network. After that, I did my MD in Calgary and I'm doing my residency training here in Toronto before starting the clinic here about eight and a half years ago.
Dr. Jean-Phillippe Miron: [00:03:04] So my name is Jean-Philippe Miron. I'm a fellow here at the rTMS Clinic at Toronto Western. I'm doing a two year fellowship. I did my residency in psychiatry at the University of of Montreal.
Henry Barron: [00:03:18] Great. So maybe could you get a bit of background on what rTMS is and how it works?
Dr. Jonathan Downar: [00:03:25] Sure. Absolutely. So our rTMS is repetitive transcranial magnetic stimulation. It's a treatment that uses a magnetic field generator that makes a powerful, focussed magnetic field that is as strong as the one in an MRI scanner. So 2 to 3 Tesla, but focus into an area that can be as small as the size of a dime by applying these focussed magnetic pulses to the surface of the cortex, it's actually strong enough to induce action potentials in the tissue. So classically, if you place the stimulator over the motor cortex, over the area that moves the thumb and you apply a few pulses, you'll actually see the person's thumb move. And if you go high enough, you can get the whole arm to move in it sufficiently high intensities and durations, it's powerful enough to induce seizures, although we generally try and avoid that for therapeutic purposes.
Henry Barron: [00:04:07] Great. And how are you using it to treat mental illness?
Dr. Jonathan Downar: [00:04:10] Great. So for the last 20 years, rTMS has been applied to regions like the dorsolateral prefrontal cortex, which have been shown to be underactive in things like major depression. And by bringing somebody in and doing hundreds of simulations per day, day after day after day, over a course of anywhere between 15 and 30 to 40 sessions, a person can improve all the way to remission from depression. What's nice is that the mechanism is completely distinct from that of standard antidepressant medications. So even people who fail the large number of antidepressant medications have an equally good shot at remitting on rTMS overall current remission rates and the published literature and the most recent studies are about one third of people achieving full remission, one third of people showing nothing at all, and one third of people showing somewhere in between that maybe a 40 to 60% improvement.
Henry Barron: [00:04:56] Awesome. What are the drawbacks or side effects adverse effects with rTMS?
Dr. Jean-Phillippe Miron: [00:05:03] So they're actually pretty advantages compared to medication. So medication obviously has a lot of neurological side effects dizziness, for example, GI side effects, nausea, stomach upset, you know, and in long term, there's weight gain, loss of libido. And the great thing about rTMS is that is it does nothing of these things. You know, there can be pain during the treatment. But usually, again, I'm pretty forward with patients. I tell them, you know, yeah, there is some pain involved. I'm not going to lie to you. But I reassured them by saying, you know, it's only a few first sessions are the toughest, but then people, they get used to it pretty quickly. And it's not treatment limiting. You know, when you do again, when you study the dropout rates because of the pain are extremely low. I did a chart review recently, about 200 patients who are using probably the most painful protocol. None of them dropped out because of the pain, even though they report pain. But so most people are able to power through this. There can be headaches and fatigue afterwards, but these are usually time limited. So our TMS is really great in that sense.
Henry Barron: [00:06:06] What about any long term effects? Have there been any studies that show that there may be or might not be long-term effects with our TMS?
Dr. Jean-Phillippe Miron: [00:06:15] So there's been no long, long-term studies done. Maybe there are some people working on that, but there's no evidence that it would bring any like long term harm. For example, I think that some people might be scared of our rTMS because of that. We use electromagnetism. You know, it's like I power lines and, you know, magnetic field. I think it's important to say that there's never been any solid scientific evidence that magnetic fields can cause cancer or harm in the human body. So there's no known actually long term side effects. And if some people sometimes report, oh, I'm feeling worse at the beginning with with TMS again, it's usually time limited after a few sessions is going to go away and we know evidence of arm in the long term so far that we know of.
Henry Barron: [00:07:04] All right. So if I'm a psychiatrist and I've got someone in my office and I'm trying to decide whether or not to refer them for our TMS, how do I know whether I have a good candidate sitting in front of me?
Dr. Jonathan Downar: [00:07:14] Okay, great question. So when you're looking at a patient, generally our TMS is reserved for treatment resistant depression at present. So that's. Usually a person who's failed at least one adequate dose and duration trial of medications. And more commonly people have failed two or three or five. So anybody who's failed at least one medication, the remission rates that are published for RTMs begin to exceed the remission rates published for sequential additional medication trials. And so if you have a patient has failed at least one antidepressant and they live relatively close to in our TMS clinic, it's worth considering if they failed a lot of antidepressants, then, even if they live far from our clinic, it might still be worth considering. So our rTMS is sort of beginning to occupy a position in the treatment algorithm that sits after medications and therapy. But before you proceed to Ect, Right. How would you say that our rTMS fits in with ECT? Because I think a lot of times people think of neurostimulation and sort of the end of the line and ECT being as effective as it is. How do you think the two compare?
Dr. Jonathan Downar: [00:08:15] Well, so they sit on different ends of a spectrum of I guess efficacy versus tolerability. So some treatments are less efficacious, but they're very tolerable, others are very efficacious, but they're just not as tolerable or they're invasive or they're costly and so on. So ECT has a higher invasiveness than RTMs because it requires anaesthesia, because it does involve seizure induction and because you have side effects of memory disruption which are troublesome for many patients and distressing for many patients. And then on top of that, the access problem is there. So even if everybody in the world with treatment resistant depression wanted to come for ECT, the reality is that our ECT capacities are limited by our time and the availability of anaesthesiologists and so on. So, so ECT has advantages and disadvantages. rTms is much more tolerable in the sense that it's less invasive and not needing anaesthesia. The seizure risk is very low. You're not trying to induce a seizure, there's no memory impairment. In fact, people have tried to use it to enhance memory. The effects are weak but not negative. And on top of that it says, I say it's more accessible, so you don't need over time, it can be done on an outpatient basis in a few minutes of treatment. The wait lists are shorter. It's potentially something you could scale up to have in every hospital, every clinic in the world if you really wanted to. And the cost is coming down all the time.
Dr. Jonathan Downar: [00:09:34] So it may eventually be something you can do at home. I think it's unlikely we're ever going to have ECT at home for people. So our rTMS I suppose is better in terms of access and tolerability and side effect profile and invasiveness. So that's why it's something that I think we try after medications and therapy have failed. But if it doesn't work, then you can proceed on to I want to clarify that our rTMS is not the same as ECT light. It's just the difference in remission rates. It's different kinds of patients who do well. On our TMS, we find that our TMS is particularly effective in the cluster B patients, even the borderline trade patients who are, you know, have lots of impulse control difficulties and struggle with cognitive control over and above their depression. Whereas with ECT you tend to get better effects, particularly in psychotic depression and in catatonic depression. Our TMS does not do well for psychotic depression. In fact, patients with psychotic illness are generally the ones who do most poorly on our TMS. So it's not just that our TMS is like a milder version of ECT. They're actually treating different groups of people, and the people who do well in our TMS often have trouble tolerating the side effects of ECT. Whereas the people who don't respond to our TMS with psychotic depression often do very nicely. And so I believe they're targeting different networks and different populations.
Henry Barron: [00:10:52] One of the drawbacks to TMS is the fact that the effect doesn't last forever. It seems to go away in patients depending on how fast they respond and and other factors. But it seems to go away after about four months on average. So I think the question that some people have is if this is a temporary solution, how can we make it more long lasting and more sustainable for people?
Dr. Jean-Phillippe Miron: [00:11:13] Yeah, so that's a good question. And I think people do kind of they kind of bit the whether they're surprised by the fact that it's not lasting forever. But I just explain to them, well, there's nothing in psychiatry that we do that unfortunately lasts usually lasts forever. You know, if you stop medication, you stop therapy, your your relapse rate are going to increase. And with our TMS, we don't have solid data on Canada, the long term stability or long term benefits. But like you say recently, the meta-analysis are kind of showing us that it's a bit similar to like it's maybe a 50% relapse rate at six months, something like that. Um, so what I tell people is that, well, it's normal, first of all, and if you do have a relapse, you come back, we do a second round of treatment and then we can do what we call maintenance RTMs and it's maintenance. Rtms is actually much less intensive than you would believe. You know, the kind of standard maintenance RTMs that we do is about one session every two weeks. So it's it's kind of convenient. It's like.
Henry Barron: [00:12:12] 5 to 10 minutes of stimulation every.
Dr. Jean-Phillippe Miron: [00:12:15] Every two weeks can be enough on a general level it can be. But again, we don't have good studies on long term data for for RTMs. We're going. Maintenance. But again, if it worked once, there's no reason to think that it doesn't work again and can be used long term.
Henry Barron: [00:12:30] Great. And how is rTMS changing or is it changing the way we see psychiatry and the way we practice psychiatry?
Dr. Jonathan Downar: [00:12:37] Well, I think it's certainly having an effect in terms of patients who sat in that that 2% of the population sits in that difficult treatment resistant depression category. So these are people who fail to respond to medications and therapy, but maybe aren't ready to go to ECT or can't access ECT. In Ontario alone, that's hundreds of thousands of people. And in the city of Toronto, that's probably over 100,000 people. So it's a new treatment option for folks like that. The other thing is that by looking at the basic science of rTMS, we're learning about what it's actually doing to get people out of depression. And what we think is happening is that it's not actually treating the depression directly. Rather, when you place it over the standard areas like the dorsolateral prefrontal cortex, probably what we're doing is we are strengthening the integrity of one of the brain's 17 major networks. And this particular network is called the Salience Network. What we believe it does is cognitive control, the ability to self-regulate your thoughts and your behaviours or your emotions. And by applying rTMS, some but not all patients with depression have a more general problem with cognitive control. You can recognise these patients because they have a lot of cluster B co-morbidities and impulse control comorbidities. So we find that the best patients for TMS are the ones who have yes, they have depression, but they may also be on the bipolar spectrum or they may have binge eating or they may have ADHD symptoms or a little bit of PTSD or a little bit of OCD.
Dr. Jonathan Downar: [00:14:00] In fact, the salience network turns out to be underactive across most axis one disorders. They're all different, but they have a common trans diagnostic deficit of cognitive control. When you apply the treatment the patients report that they have, they actually generally report that, "yes, my mood is improving. But what I really noticed is I have more self control. I have better ability to resist the urge to binge eat. I notice I'm more focussed in conversations. If I want to stop thinking about something, I can stop thinking about something." And the ones who have previous experience of therapy, like cognitive behavioural therapy or DBT, they'll often say in the past they have theoretical understanding. "I know what I'm supposed to be doing, it just doesn't work." And then when you restore the integrity of their salience network with RTMs, then they'll come in and they'll say, "Oh, you know, I started using my CBT techniques and they work now." So we think that's what RTMS is really doing. It's strengthening cognitive control, and the best patients to send for our tests are not just the ones with depression, specifically the ones who have a variety of different diagnoses and co-morbidities, whose common element is a lifelong, pervasive trans diagnostic deficiency in cognitive control.
Dr. Jean-Phillippe Miron: [00:15:07] I think it's really making our conception of mental illness shift a lot because we go from thinking more in maybe psychodynamic terms or maybe in terms of the neurotransmitter theories of depression. We're shifting from that more to brain networks and brain connectivity, and we're getting closer to actual clinical neuroscience. There's some resistance, especially in the psychiatric field, I find, even though there's been many randomised controlled trial, but there's this there's still a lot of sceptical psychiatrist. Slowly it's opening up. But I think a lot of especially clinicians, they kind of feel that we think that RTMs are going to be the one solution and that's it. But I see RTMs as a solution when it's combined to other things such as therapy and medication.
Henry Barron: [00:15:58] Great. So what do you think is next in the area of RTMs? What's exciting and up and coming?
Dr. Jonathan Downar: [00:16:05] Okay, so there are a few different areas where RTMs is progressing. It's actually quite quick progress right now. I think we may be finding ourselves in a sort of golden era of Neuromodulation in the same way that, you know, back in the 1950s to seventies, we were sort of in the golden era of psychopharmacology. So one area of discovery is more cost-effective treatments. In the old days, RTMs was quite a long duration session, so you had to bring the person into the chair for anywhere between 30 and 60 minutes per day. For example, the FDA protocol originally approved in 2008 for depression, is a 38 minute protocol. Now that means that the machines can't treat very many people each day, and that keeps the costs up and the waitlist long and the capacity is low. One of the big advances of 2018 was a large Canadian study called three D, and in the three D study, the Canadian centres, of which we were one of the three ones, we tried out a new kind of stimulation pattern that mimics the brain's theta rhythms, and it's called theta burst stimulation. And the main feature of theta versus stimulation is induces plasticity very efficiently in the brain.
Dr. Jonathan Downar: [00:17:12] So you get the whole job done with 600 pulses in 3 minutes instead of 3000 pulses over 38 minutes. The big question wasn't whether it did better than sham. The question is how did it do? Or to standard of care. And the three RD study was designed to assess that. What it found was that the three minute treatments were every bit as effective and numerically superior, although not statistically superior to to the standard conventional treatments. So you didn't get better outcomes, but you did get an ability to get the same outcomes with just 3 minutes of treatment. That means the appointments can be reduced to just ten or 15 minutes. And so that means that every machine in the world can treat many times more people and as a result, the cost per treatment can come down quite a lot. So I think more countries and more jurisdictions and more individuals are going to find it to be an affordable treatment. They're also going to notice the wait list is four or five times shorter than it was before.
Henry Barron: [00:18:02] Another thing that I've seen in this clinic is the idea of maybe bringing RTMs to the home, making it cheap enough for people to afford and do on themselves.
Dr. Jonathan Downar: [00:18:12] Mm hmm. So that's actually that's one of the up and coming things that I think is going to be necessary to make RTMs a real sort of viable alternative to medications for a large number of people. One thing you say about medications, whether you love them or you hate them, they're very convenient. You don't really have to spend a lot of time doing them. You don't have to come into the hospital for them. They're just there for you at home. So we've had a longstanding goal to try and figure out how to get the brain stimulators home to the patients instead of the patients to the stimulators. It looks like there may be ways to do protocols that are maybe a bit longer, like 8 minutes long, but are extremely safe and simple to do, maybe safe and simple enough that we could teach people to do them at home, just as we teach people on exactly their own insulin or to do other kinds of care on themselves. The devices that used to cost 200,000. Now have some versions that are as little as 10 to $15000. And so there's a possibility that if you take out a loan every five years or so that we might be able to get the daily costs of the treatment down to as little as 5 to $10 a day. So $5 a day. RTMs at home achieving superior effects of medications while having fewer side effects and a superior safety profile. Since you can't overdose on your RTMs machine, it can be programmed to lock you out so you just use it once a day, or only according to the prescription. So this is one of the things we're looking at. And I think bringing our TMS home to people, which may be possible in the next 4 to 5 years, I think that would be a real game changer, especially if the cost can come down.
Dr. Jonathan Downar: [00:19:42] Other things that people are looking at now that the treatments are just 3 minutes long. A lot of people are looking at doing multiple sessions per day. Now, if you just give people our TMS back to back to back with no gap, the extra pulses don't seem to do very much. But if you give the brain an hour or two to recover between sessions, it might be possible to do more than one session per day. So it's possible that you may not have to wait a full 24 hours between sessions that for some people you can actually do multiple sessions a day. In Belgium, Chris Bakken is a professor who's looking at four times a day or five times a day. Stimulation. Paul Fitzgerald in Australia is looking at three times a day stimulation. Other folks have looked at five times a day stimulation. And and in Stanford, Nolan Williams is looking at ten times a day stimulation. So people are trying lots of different parameters out. We've tried we've recently completed a trial looking at twice a day versus once a day with some very careful controls built in to control for a placebo or a non-specific effects. And it looks like doing two three minute sessions back to back doesn't speed things up. But if you put a 60 minute gap in there and you do the stimulation 60 minutes apart, then the TMS may work faster. For some people, it doesn't seem to achieve an overall higher remission rate, but at least if you are going to respond, then you'll respond more quickly.
Henry Barron: [00:20:58] Great. One of the things that I also think was really helpful potentially for the people who are trying to get RTMs to work for their patients was you have a checklist approach to when RTMs doesn't work, What factors should you try to address?
Dr. Jonathan Downar: [00:21:13] So in general, the rule we've found is that if you get to 15 sessions or usually three weeks of stimulation and you haven't achieved at least the 20% improvement, then that particular protocol is unlikely to keep working. Something is up. We have a checklist of about six things you need to look at, and that includes see whether you've got the right diagnosis, whether the patient may be on some medications that block RTMs like the Gabaergic medications like benzodiazepines, Pregabalin and Gabapentin anti-epileptic medications like the motor gene and and Topiramate are also reckoned to potentially block the plasticity of RTMs. Then you have factors inside the room. Maybe the person couldn't tolerate the stimulation, so you couldn't turn up the intensity high enough you have outside the room factors. Maybe the person's getting better coping capacity thanks to you work on their salience network. But if they're in a really stressful situation, like they're still working in a job or they're being harassed or they're still living at home in an abusive relationship, then it might be very hard to see what's changing. Aside from that, it's possible that you're targeting the wrong circuits or you're targeting the person's salience network. But in fact, their pathology is coming from a different network in the brain. So now looks like in depression some people have a lack of salience network and a lack of cognitive control, but not all patients do.
Dr. Jonathan Downar: [00:22:30] Others may be having other networks that are driving their symptoms, and so sometimes moving the coil to a different spot on the brain will actually will give you another 25% remission on top of the one third we see on the first run. However, when all those things fail, we have to acknowledge that. We believe that about one out of three people, no matter where on the brain, you stimulate them. With our TMS, you can always activate them, you can always get the action potentials. But some people don't show plasticity, so they don't get a durable effect from the TMS and we don't know how to test for those people yet and we don't know what to do about it when we see it. So that part is a diagnosis of exclusion. But if we see a non responder, we generally go through that six point checklist to see if we can spot what's going on. If there's something to fix, we fix it. If not, we try a different brain area and if we try out a few brain areas and nothing's work, then at that point we would declare a failure and we would work on the assumption that maybe they just don't have the plasticity from our TMS.
Henry Barron: [00:23:23] Great. And then sort of a last question to wrap up. Do you have any words of advice for budding psychiatry residents or medical students who are interested in the field?
Dr. Jonathan Downar: [00:23:32] Sure, absolutely. I'd be happy to say so. I mean, as a clinician scientist, I can say that there's there's a lot of reward to it because you have scientists who are doing the research and publishing the papers, but often not in direct patient contact. And then you have MDs who see a lot of patients, but they don't always have time to read the scientific literature. Clinician scientists have to have a foot in both in both worlds. So they're seeing patients and they're working in clinics, and they're also reading the science literature and becoming familiar with it. But clinician scientists ideally do a lot of translational work, so they're looking at results from the literature and saying, How could we turn this into a treatment? In my example, it would be the case of saying, Well, our patients were suffering a waitlist problem with our TMS because the sessions are too long. But fortunately, having read the literature, we would hear about these treatments like theta bursts that were being used pre clinically and motor cortex, and we noticed they were only 3 minutes long. And so the translational question becomes, well, how do the these three minute treatments compare in in real world patients to the 38 minute treatments? So that would be the sort of translational question that a clinician scientist can ask. The reward of being a clinician scientist is that you see your research being directly translated into better patient care, and that's a very rewarding thing to to experience. The downside, of course, is that you're sort of working two jobs. So you'll see the joke is that clinician scientist is 75% clinical in 75% research. So usually you're you're spending a lot of evenings and weekends catching up on the science work you didn't get to do during the daytime.
Dr. Jonathan Downar: [00:24:58] And so you do have to find some question that you're so passionate about that you're willing to give up some of your free time and that you could be spending with friends or family to sit down and work in the lab and try and build the treatments. So that's the downside of it. As for is this, you know, is this the career for you? I recommend that when you're early in your training, the best thing to do is take areas that you think you might be interested in and do some rotations in them. But then if you think you've established an interest, don't forget to also look at other areas to really confirm that that's what you want to do. See if you're interested in, say, clinician scientists and psychiatry, go in and shadow a clinician scientist for a while and maybe do a rotation with them, but also look at other areas of medicine, look at other areas of psychiatry and do other rotations there. You may find that one of those just speaks to you more, that you're more passionate about it, or you may find that none of those areas are interested. And now you can be really confident in your decision that you've sampled a lot of different areas and you're sure that out of all those areas, this one particular one is the one you want to do. So I think that's what I can say is really once you think you know what you're interested in, try other things as well, just to be sure.
Henry Barron: [00:25:58] Great. It's been a pleasure having you on the show, Dr. Downer, thank you so much for your time. I'm sure that everyone's going to really appreciate the words of wisdom that you imparted.
Dr. Jonathan Downar: [00:26:07] Fantastic. Thanks for having me on the show and I hope it goes well. Cheers.
Christina: [00:26:22] Okay, So now that you know a bit more about RTMs, we thought it would be nice for you to understand a bit more from the patient perspective. So here's Henry getting a bit of an understanding about what that feels like.
Henry Barron: [00:26:38] Okay. So, uh, do you want to just introduce yourself briefly?
Christina: [00:26:43] Hello, I'm Sonia Goldberg, and I'm one of the RTMs techs at this clinic.
Henry Barron: [00:26:48] Do you think we should do, like, actual. I just don't want to, like, zap the microphone.
Christina: [00:26:54] Or the microphone. Yeah, we can maybe put the microphone over.
Henry Barron: [00:26:58] Yeah, I could. I could turn it up to, like, Max and maybe, like, put it over there.
Christina: [00:27:02] I just don't want to break your microphone, honestly.
Henry Barron: [00:27:05] Yeah. Just go like this.
Christina: [00:27:13] Yeah. Okay, perfect. So have a see. We're going to do something called a modem threshold on you today, which is basically we're going to be using the magnet on your head to see at which amplitude your arm moves. Okay, so it's uncomfortable. I won't say it's painful. We're going to be using about 0.2 pulses per second.
Henry Barron: [00:27:35] Okay.
Christina: [00:27:36] So it won't be very quick and it won't be like a treatment.
Henry Barron: [00:27:39] So it's not going to hurt at all. It's just going to be like.
Christina: [00:27:41] It'll be uncomfortable.
Henry Barron: [00:27:42] Okay.
Christina: [00:27:42] All right. It'll feel tingly and weird and uncomfortable. And depending to where which amplitude we get, there may be a little bit of pain involved, but I don't anticipate there being too much.
Henry Barron: [00:27:52] Cool. Okay.
Christina: [00:27:53] So what we're going to do is we're going to have you have a seat. Sure. Remove anything bulky from your pockets or your lap. Okay. Sit down. Lean back a little bit. Head forward. Arms on the armrest and palms facing up just as loose and relaxed as possible. Cool. Are you comfortable like this? Okay, so we're going to get started. We like to start at an amplitude of 35. And what I'm going to do is I'm going to take the coil and I'm going to place it halfway between the top of your ear and the vertex of your head. And we're going to start there and just move around to see where we get a stronger impulse.
Henry Barron: [00:28:34] Okay. So you're looking to see how much how strong the magnetic field has to be for my for my hand to twitch, right?
Christina: [00:28:40] Correct.
Henry Barron: [00:28:41] And so that's sort of like you're testing to see if it's going to be strong enough to actually affect my brain.
Christina: [00:28:47] Yes. So we're going to we're going to be trying to stimulate your motor cortex because it's about the same depth as the area that we're trying to stimulate to treat you. Okay. So we're going to start at 35. Just tell me if you feel pain. That's above a seven or eight and then we'll stop. Okay, great. So 3 to 1. So that's us ramping it up to 35.
Henry Barron: [00:29:16] Okay, so I'm getting like a tapping feeling out of my scalp. Yeah. And like, my face is twitching a little bit.
Christina: [00:29:21] Too, so that's totally normal. You're going to feel some twitching. I want you to tell me when you feel twitching in your arm. Okay. I'm going to move up a little bit. Okay. Okay, so I see some movement in your arm since we're stimulating the left side. I'm going to see movement in the right. Okay, So is that very painful?
Henry Barron: [00:29:43] It's hard to describe. It's kind of the first couple of ones were kind of shocking. But after that, it it's not as bad. It just kind of feels like someone tapping really hard on my head.
Christina: [00:29:53] I guess that's how most patients describe it. So that's what the motor threshold is like. The treatment itself is going to be a little bit faster paced, but it's only 8 minutes and 24 seconds for a one hertz treatment.
Henry Barron: [00:30:08] Oh, wow.
Christina: [00:30:09] So six trains of 60 seconds, one pulse per second, 30 seconds off between each train.
Henry Barron: [00:30:16] Awesome. Cool.
Christina: [00:30:17] Okay. Well, thank you for coming for treatment.
Henry Barron: [00:30:19] Thank you. Thanks, Christina.
Christina: [00:30:33] PsychEd is a learner driven initiative led by residents at the University of Toronto. We are affiliated with the Department of Psychiatry at the University of Toronto, as well as the Canadian Psychiatric Association. The views endorsed in this episode are not intended to represent the views of either organisation. This episode was produced and hosted by Henry Barron. Alex Rayben voiced the introduction. Audio editing was by Henry Barron and Alex Rayben. Our theme song is Working Solutions by All of Music. A special thanks to Dr. Jonathan Downer and Dr. Jean-Philippe Miron for serving as our guest experts on this episode. And thank you to Ksenia Gorenberg, who provided our TMS technical expertise on the episode. As always, we'd love to hear your feedback and you can contact us at info podcasts or visit us at Psych podcast. Org. Thanks so much for listening.