Vagus Nerve Stimulation has been on my radar for some time but recent developments, especially in our understanding of the Brain-Gut connection have me paying more attention to what’s happening in VNS research. This post will serve as a simple introduction in hopes of inspiring your own curiosity and I’ll fill in the blanks as more information becomes available. Overview from Wikipedia: Vagus Nerve Stimulation.
And finally a couple of device manufacturers with products currently on the market. I have zero relation to any of these companies and am linking to them simply so you can see what the devices look like and how they are marketed. There are probably many more. gammaCore NEMOS Monarch
Not tDCS, but EEG used in an new and exciting way.
At this time, she is recalling a previously trained hand gesture: a pinch with her fingers. This happens without removing her hands from the bowl to touch the screen. Just one thought.
This is exactly the case 22 seconds in. Notion detects her intent, and creates metadata that contains this information.
A split second later, thought-based intent turns into reality. As the mobile device receives the intent command created by Notion, the imagined hand gesture pattern is associated with a computer command. In this case, a scroll down event is executed. This happens repeatedly. She scrolls the page, allowing her to continue reading without lifting a finger.
From: You can now think to scroll
More at Neurocity.co
As more of these advanced, less expensive EEG chipsets come to market we can expect to see devices which merge EEG with non-invasive brain stimulation like tDCS or tACS. Applications I’ve seen discussed in the literature suggest that researchers would use specific EEG signals to trigger NIBS to specific areas. For example if the process your brain were doing at this exact moment required optimal functionality from a specific part of your brain, non-invasive stimulation would kick in to assist at that area.
It’s important to keep in mind that this is all speculative and mostly imaginationware at the moment. What I see as a trend in recent research is that the picture is in fact becoming more complicated, implying we know less than we thought we did. Further complications arise as we begin to understand how unique each of our brains are.
I’m not sure how useful a device that allows me to scroll down just by thinking of it will be to the general population. But certainly for people with physical impairments a lower cost, state of the art device that actually does something could be life-changing. Can you think of applications for the Notion that would entice you to own one? Not yet available but you can get on the get on the waiting list of request a Developer Kit here.
In this study, we want to see if a five-day course of tDCS combined with fluency training will improve speech fluency more than the fluency training on its own. We also want to see if such improvements are maintained over a period of three months.
The men’s tDCS study is represented in this diagram.
That’s what I remember thinking the first time I figured out that they were talking about opening your skull and planting electrodes into your brain. Then I thought… Imagine being so desperate that that would seem like a sensible next step in your course of treatment. And then I thought… Wouldn’t it be amazing if tDCS, Focused Ultrasound, or now Temporal Interference, could replicate the results without the surgery.
Recently the always excellent Invisibilia podcast covered DBS as applied to depression and OCD. We hear from the patient, her boyfriend and the doctors involved. I have a completely new understanding of the procedure and its effects. I highly recommend a listen to this episode.
Nicely done (for a media outlet) six week experiment to test efficacy of HaloNeuro‘s Halo Sport tDCS device. Elise’s takeaway is that she wishes the effect was a little more dramatic. But her trainer tells her that extra 1-1/2″ is actually significant. Certainly in pro sports settings I’m sure it would be. Nice overview of hypothetical understanding of how tDCS works. She also interviews HaloNeuro co-founder Daniel Chao and Olympic volleyball athlete Kim Glass. Elise on Twitter
Many years ago, perhaps even as a boy, I saw this clip of Wilder Penfield eliciting memories from brain surgery patients, and it really stuck with me. Probably the notion of one’s entire stream of consciousness existing somewhere in the brain waiting to be unlocked with a bit of stimulation is incorrect, but nevertheless, to hear these actual recordings of patients suddenly recalling events from their past is fascinating.
My question is, Why can’t non-invasive brain stimulation, like tDCS, evoke similar responses to those outlined in these two videos? If it’s that tDCS stimulates too broadly, then perhaps something like Temporal Interference (where stimulation occurs at the point where two frequencies meet) could be used to stimulate these areas. Certainly an experiment worth thinking about.
“Older people’s memory got better up to the level that we could no longer tell them apart from younger people,” said lead investigator Joel Voss, associate professor at Northwestern University Feinberg School of Medicine. “They got substantially better.”
Not related directly with the research, but interesting to note in the video where Canadian researcher Jed Meltzer, a scientist at Baycrest Hospital’s Rotman Research Institute in Toronto is shown demonstrating an ActivaDose device and an unusual montage.
Tyler Cowen interviews Ed Boyden of MIT in this excellent interview. (Seriously, listen to this interview).
Ed Boyden is a neuroscientist and his lab, Synthetic Neurobiology Group is serving up a steady stream of cutting edge brain research. Especially of interest to DIYtDCS viewers is his involvement in a new form of non-invasive brain stimulation able to reach deep into the brain…
The method, called temporal interference, involves beaming different electric frequencies, too high for neurons to respond to, from electrodes on the skull’s surface. The team found that where the currents intersected inside the brain, the frequencies interfered with each other, essentially canceling out all but the difference between them and leaving a low-frequency current that neurons in that location responded to, Dr. Boyden said.
You may have noticed that I’ve not been posting as much to the blog lately. The blog is already so full of useful content for anyone looking into tDCS that I’m inclined to only post significant information that would move our current understanding of tDCS and neurostimulation forward. This article/paper describing a new technique using ‘HD tACS’ to synchronize (brainwaves) parts of the brain definitely looks intriguing and has implications for anyone paying attention to DIY neurostimulation. Very early, but very interesting.
“These (medial frontal cortex & lateral prefrontal cortex) are maybe the two most fundamental brain areas involved with executive function and self-control,” says Reinhart, who used a new technique called high-definition transcranial alternating current stimulation (HD-tACS) to stimulate these two regions with electrodes placed on a participant’s scalp. Using this new technology, he found that improving the synchronization of brain waves, or oscillations, between these two regions enhanced their communication with each other, allowing participants to perform better on laboratory tasks related to learning and self-control. Conversely, de-synchronizing or disrupting the timing of the brain waves in these regions impaired participants’ ability to learn and control their behavior, an effect that Reinhart could quickly fix by changing how he delivered the electrical stimulation. The work, published October 9, 2017, in the journal Proceedings of the National Academy of Sciences (PNAS), suggests that electrical stimulation can quickly—and reversibly—increase or decrease executive function in healthy people and change their behavior.
Here’s the paper (paywall): Disruption and rescue of interareal theta phase coupling and adaptive behavior. The supplemental pdf. describes the equipment used in the experiment. High definition transcranial alternating current stimulation ( HD- tACS ). The alternating current stimulation was administered noninvasively using an MxN9-3 channel high definition transcranial electrical current stimulator from Soterix Medical (New York, NY). Eight sintered Ag/AgCl electrodes were attached to high-definition plastic holders, filled with conductive gel, and embedded in the Biosemi EEG cap. HD-tACS electrode placement was guided by current-flow modeling using HD- Explore and HD-Targets (Soterix Medical), with the goal of targeting the MFC and lPFC to facilitate the synchronization of neural activity between these regions (the in phase protocol ) or disrupt the signals being conveyed between the MFC and lPFC (the antiphase protocol ).
Listen to Bob McDonald discuss HD tACS with Prof Rob Reinhart on the always interesting Quirks and Quarks.
[Update 3/18/19] Exciting news in the fight against Alzheimer’s! Dr. Tsai has a new lab. Tsai Laboratory
In the new study, researchers added acoustic stimulation that pulsed at the same frequency as the visual stimulation. And when mice — which were bred to develop Alzheimer’s-like symptoms — were exposed to both, researchers saw that the neurons in several of their brains’ key memory circuits chimed in and began humming along at exactly the same frequency. What came next was remarkable and unexpected, even to the authors of the study. In the wake of the sound and light sessions, an army of newly energized immune cells descended on several areas of the treated brains, including those most affected by dementia. Then they set to work with a vengeance on some neglected housecleaning.
LA Times https://www.latimes.com/science/sciencenow/la-sci-sn-alzheimers-brain-waves-20190315-story.html
The paper, Gamma frequency entrainment attenuates amyloid load and modifies microglia makes clear that the light-flickering affected the visual cortex, which makes sense, as the light reaches the brain through the eyes. But wait, thinks I, what about tACS (transcranial Alternating Current Stimulation)… haven’t I seen numerous papers implying the ability to ‘entrain’ brain waves with tACS? What if you could increase 40hz Gamma in other parts of the brain? (Google Scholar Search: transcranial alternating, entrain, gamma) But then I discovered that Radiolab just covered this exact story and it’s totally amazing! Really a must listen. So fun to hear the researcher’s amazement at this accidental (sort of) discovery! So what’s with the photo of the Foc.us v2 device set up for a 40hz tACS session? Just that…
This video shows what is included with the Activadose tDCS Starter Kit from Caputron as well as a quick start guide. For more in depth look at how to use the device or to purchase this device, visit Caputron.com (As mentioned elsewhere on the blog, I have an affiliate relationship with Caputron. If you purchase any product from Caputron using code diytdcs at checkout, you will receive a discount and I will receive an affiliate fee.)
Neuroscientist Daniel Chao created a headset that hacks your brain with electricity so you can learn as fast as a kid again. It’s called Halo, and it helps you learn motor skills faster. Athletes use it; musicians too. But we’re not far from a future when Halo could help anyone master anything. Where will that take us? Host Caterina Fake leads the journey, joined by Comedian Baratunde Thurston and Quartz Editor in Chief Kevin Delaney, who help Daniel future-cast, and see his invention through the future best for humanity.
Michael was told he had reached his limit on what he could do. This was not something Michael and his partner, Jason, would accept. They began to look for other options and found Johns Hopkins Physical Medicine and Rehabilitation’s Non-Invasive Brain Stimulation (NIBS) as Michael’s answer to improve. Watch to learn more about Pablo Celnik and his team’s approach to setting Michael on a path to recovery.
From a comment to the blog. Doc Johnson shares this beautiful DIY tDCS build. Thanks Doc!
I’m personally just beginning experimenting with TDCS, and as an avid DIYer, I built my own. The open designs I’ve seen seem to be a little short on features (particularly a fail-safe over-current protection), so I decided to use my background as an Electrical Engineer to start from scratch. It might be useful for others who are interested in building their own.
The design incorporates a feature that trips something equivalent to a circuit breaker if more than about 4.8mA of current flows through the electrodes. It should never happen based on the current regulator design, but I’ve seen too many pieces of silicon short out in a way that would be dangerous in this situation. I finished testing the design this weekend, and am quite happy with it. All told, the parts are about $20, not counting the hours spent designing, building, testing, redesigning…
The design and links for how I built the circuit board are located at https://www.diligent5.org/?p=1993 I built it using surface mount components because I like the tighter resistor tolerances available, but theoretically the components (or something equivalent) are available as through-hole components for the less adventurous. Cheers, Doc Johnson