Brain stimulation can be a bit of a queasy topic for some people. I used to be among them. Where I grew up –Holly Springs, NC – there wasn’t a lot of public education on psychiatric health to clear my uncertainties. Any talk about brain stimulation would conjure scenes of austere hospitals, sedation, the verb “to zap,” and convulsions. In any case, I thought those types of medical practice were an artifact of days past, didn’t help the people they were ‘inflicted’ upon, and are now long gone from today’s medicine. When I transferred to UNC, I learned otherwise. There ARE still types of stimulation that involve convulsions, hospitals, and even anesthesia, and they can help people recover from the deepest throes of depression. What’s more, there are types of brain stimulation that don’t require any of those things – brain stimulation that can be done safely at home, while conscious, and that may help depression nonetheless.
For the past year, I’ve been studying the way so-called “noninvasive” brain stimulation interacts with the dynamical electrical activity of the brain at the Frohlich Lab. Among the techniques I’ve learned (and, weird as it may have once seemed to my younger self, performed on people) was Transcranial Magnetic Stimulation (TMS), which has been an FDA approved treatment for depression since 2007. Though it shows clinical merit (it had to, in order to get the FDA’s seal of approval), it’s not the kind of thing that can be done at home. The device is huge and is usually done in an outpatient setting. What I’m talking about is different: Transcranial Alternating Current Stimulation (tACS). The Frohlich Lab has worked on multiple clinical trials that build on the possibility that this technique, one that’s safer and more portable, might show the same results. Much research is still to be done before that can be supported confidently, but the process to FDA approval starts far in advance. Though scientists study different parameters and methods of using the technique, the FDA only stamps, at first, a single, pioneering device.
This semester, I’m working as a Karen M. Gil intern at Pulvinar Neuro, a local, Durham-based startup that develops novel neurotechnologies, including brain stimulators. Currently, they are developing a tACS device that simplifies the research-grade technology that is currently being used at the Frohlich Lab into a simpler form that doctors and technicians in medical settings could get used to quickly – the type of device that could get the FDA’s approval. I’m tasked with testing it.
It’s a very specific kind of testing – not the way a scientist might validate the precision of their tools before a study, or ‘testing’ in the sense of an n=20 clinical trial, but a part of the design process. The goal is for doctors to be able to use a device that (from personal experience) even researchers with a technical background can find confusing, and the only way to know if your design choices are working, or are not, is to learn from real doctors really trying to use it. This is called “formative testing,” which is a type of usability testing that’s done during the formation of the device. The results of the testing get fed back into the design process to help improve the “human factors” – how understandable is the computer interface? Is it hard to plug in the wires? What human error is the device prone to eliciting?
I’ve started writing up a protocol for how we’ll do this, and throughout the rest of the semester I will finish the protocol, develop instructional materials to help our test participants learn the device’s intended use, recruit doctors to partake in our test, run the protocol, and write up the insights. I’m excited to blaze forward with this project, not just because the documentation of design testing steps – the formative test being one of them – is required for an FDA approval bid. I’m also excited because this is a real opportunity to see, and shape, the future of the use of brain stimulators in a medical setting. Will doctors be open to it? What will we have to do to make them? Who knows, maybe I will write an instruction manual that helps doctors lose that queasiness I once had, and gives a host of their patients one more tool to live healthier lives.