Prof. Wael Asaad, Associate Professor of Neuroscience and NeuroSurgery at Brown University - burst 02
Sure yeah so. Deep brain stimulation is a well-established therapy for movement disorders in particular such as parkinson's disease where it's most often used but also for things like essential tremor You know we we also use it occasionally for Intractable psychiatric diseases such as ocd although we also do some other procedures for that And so it's basically just a method for putting electrodes in the brain to deliver electrical stimulation that can modulate the activity of brain circuits. And so it's really to be contrasted with chemical neuro modulating. Which is what you do whenever you take a pill that affects brain function and the advantages of electoral modulating are that you can target it directly to a circuit and modified that circuit irrespective of sort of the natural boundaries of chemical mediators. If you take a drug you know the circuits Vet drug works on Really sort of just depend on where evolution put them whereas you know if we have a knowledge of the circuits were trying to modulate. We can anatomically target our therapy. The of course is that you know for something like deep brain stimulation. You have to actually do no surgery and even though by our standards neurosurgery it's relatively minimally invasive and you You know relatively safe. Obviously there there are always risks associated with it. So you know. But the advantages that with neuro modulation. You can often do things that you can't do with medicine. So so in this case y the inept roads are actually going into the brain. So you actually have surgically eats your surgically inserting detroit's detroit's that's right. So we typically a pair of electrodes one on each side of the brain into the relevant circuit. And everything's implanted under the skin so nothing is visible to an outside observer and we tunnel electrodes to a battery. That's typically we call it a battery but it's really kind of a little more fancier. That's a pulse generator that on is implants underneath the skin. Im- chest like a pacemaker. Would be and the wires run under the skin to the electrodes in the head. And you know this procedure can be done Awake which is the sort of the standard way to do it. It can also be done using intra operative image guidance using c. T. or an mri. And you know but it's remarkable when it's done awake because you know the brain doesn't feel pain directly. If you know about the skin you can go and put it in there. And you find the circuit. You test stimulation to make sure that's working the way you white and patients are very very cooperative in eager to have this procedure done in many cases and it's great to see its effect immediately in the operating to work for an alzheimer's after many many disappointments be haven't been greeley able to do anything from chemical intervention perspective on do video installation say And so so. This is going in that direction right to to see if we can actually approach infamy. of a multi center trial. We were one of the sites doing testing deep brain stimulation of the memory circuits for alzheimer's disease. And what we were hoping to do was to modulate bet circuits. So that just like in parkinson's disease you know when you deep brain stimulation for parkinson's disease. You're not really changing the underlying courses the disease as much as you are kind of improving the symptoms and so the person can function better even though unfortunately disease. The disease keeps progressing. We're hoping that at least that might be the case in alzheimer's where even if we couldn't change the underlying course and it's not certain that we wouldn't be able to even if we couldn't that at least we might improve memory function and this was based on this whole trial is based on the work of of a well known neurosurgeon toronto. Under lozano who founded in a small group of patients when he was trying to stimulate a nearby area that stimulating specific memory structure called the four necks which leads the hippocampus which is kind of core structure in the episode memory system. That when he asks you know when he inadvertently stimulated this circuit patients had a sudden recall with great clarity of distant events in their lives of you know it may not have thought about for a long time which gave him the idea that maybe if we modulate the circuit we might be able to boost memory. You know again. In allergy to parkinson's disease in where we reduced the right circuit took mild outside merge dementia Do second that you have to if you want to be successful clearly has to be early. We feel that it's probably most advantageous to try and intervene early on just because there might be the best chance of changing the course of that person's disease at least in terms of symptomatic control on but you know it's not clear that that's necessarily the best way to do it but It probably makes the most sense for where to start. Yes you find this study. You finally discovered forty do Patients in the study.