In two sham-controlled experiments, we found that repeated daily prefrontal tDCS sessions over 5 several days could effectively modulate how non-depressed individuals self-assess their mood states. Results show that participants experienced less psychological distress from daily stressors, a well established cause in the establishment of a negative emotional state. We replicated this finding in an independent, randomized, double-blind experiment applying similar protocol and stimulation on 3 consecutive days.
Wait! There’s a Science Daily version.
Brain boost: Research to improve memory through electricity?
More important, the researchers identified the actual molecular trigger behind the bolstered memory and plasticity–increased production of BDNF, a protein essential to brain growth. BDNF, which stands for “brain-derived neurotrophic factor,” is synthesized naturally by neurons and is crucial to neuronal development and specialization.
“While the technique and behavioral effects of tDCS are not new,” said ONR Global Associate Director Dr. Monique Beaudoin, “Dr. Grassi’s work is the first to describe BDNF as a mechanism for the behavioral changes that occur after tDCS treatment. This is an exciting and growing research area of great interest to ONR.”
The research is sponsored by the Office of Naval Research!
What he said!
Holy crap! tDCS boosts synaptic plasticity and memory in mice via epigenetic regulation of Bdnf expression. https://t.co/QbtGcYVr8S
— Peter Simpson-Young (@PSimpsonyoung) March 3, 2016
Podda, M. V. et al. Anodal transcranial direct current stimulation boosts synaptic plasticity and memory in mice via epigenetic regulation of Bdnf expression. Sci. Rep. 6, 22180; doi: 10.1038/srep22180 (2016).
I won’t even pretend to understand this paper at this point, but it’s unique enough that I want to encourage people to have a look. That said… what I think it’s saying is that (in mice) hippocampal tDCS creates a chain reaction that results in increased brain plasticity, i.e. increased neuronal connection which in this case is responsible for increased performance in a memory task. (Not more neurotransmitters.)
But this paper suggests the actual mechanism for how this is happening.
We hypothesized that anodal tDCS induced membrane depolarization mimicking neuronal activation and triggered epigenetic changes at Bdnf, thus favoring its transcription.
All together these results indicate that Bdnf expression in the hippocampus is induced by anodal tDCS and that enhanced acetylation at Bdnf promoter I is likely responsible for such effect.
Collectively, these data suggest that anodal tDCS induced epigenetic changes at Bdnf promoters likely relying on a mechanism involving CREB activation, CBP recruitment and H3K9 acetylation.
These results strongly support our hypothesis that increased histone acetylation promoting Bdnf transcription plays a major role in anodal tDCS-induced enhancement of synaptic plasticity.
This is could be a game changer. Announced today on the Thync mailing list. New vibe available for download.
After 1 week of using our new Good Night Vibe, our participants reported:
- Improved sleep quality similar to 4 weeks of meditation or 8 weeks of melatonin
- Reduced mid-night awakenings
- Improved morning mood & alertness
- Reduced anxiety & stress
…And the cherry on top?
The same Good Night Vibe that we used in our clinical testing is now available in the Thync app for you to use!
So go ahead – run your own sleep study: Try out the Good Night Vibe for a week, and let us know what you think!
What if becoming an expert pilot were as simple as putting on a cap?
The video is based on the Feb. 9, 2016 study, Transcranial Direct Current Stimulation Modulates Neuronal Activity and Learning in Pilot Training
The researchers featured in the video, post-docs Jaehoon Choe and Matthew Phillips work for HRL Laboratories. Did they know the PR dept. was going to take their interviews and inject them with awesome graphics and all sorts of hyperbole? Is it marketing capitalizing on research, or research capitalizing on marketing?
I plan to dig deeper into this story and update as more info emerges and I get a better understanding of the study.
Excerpt from an interview with clinical neuroscientist, Kate Hoy. The paper referenced is Testing the limits: Investigating the effect of tDCS dose on working memory enhancement in healthy controls
What is the most surprising or interesting research case you have worked on?
The findings where the data doesn’t show what you expected are always the ones that mean the most. In one study we were looking at the effect of gentle electrical stimulation (tDCS) on memory in healthy people; we compared sham (‘fake’) stimulation with a low and a high dose of tDCS. My hypothesis was that the higher the dose the better would be the performance and I couldn’t have been more wrong. The findings showed that the sham stimulation did nothing (as predicted), the low dose improved performance significantly, and the high dose behaved most similar to the sham stimulation.
This puzzled us so we brainstormed the findings and came back to the idea of homeostasis, where you can push the healthy brain a little but if you push it too much it will ‘push back’. Essentially, there are only limited gains in brain function that can be achieved in the healthy brain. That finding, which was from an Honours project, that I had initially worried was uninterpretable, resulted in a publication, two current PhD projects, and set me off on a different path with this aspect of my research.
Great example of exactly what we’re up against. The study in the previous post found no effect on Working Memory in older adults targeting dorsolateral prefrontal cortex (dlPFC). This study did find a positive effect on Episodic Memory in older adults targeting left lateral prefrontal cortex (PFC).
Episodic memory displays the largest degree of age-related decline, a process that is accelerated in pathological conditions like amnestic Mild Cognitive Impairment (aMCI) and Alzheimer’s Disease (AD). Previous studies have shown that the left lateral prefrontal cortex (PFC) contributes to the encoding of episodic memories along the life span. The aim of this randomized, double-blind, placebo-controlled study was to test the hypothesis that anodal tDCS over the left lateral PFC during the learning phase would enhance delayed recall of verbal episodic memories in elderly individuals. Older adults learned a list of words while receiving anodal or placebo (sham) tDCS. Memory recall was tested 48 hours and 1 month later. The results showed that anodal tDCS strengthened episodic memories, an effect indicated by enhanced delayed recall (48 hours) compared to placebo stimulation (Cohen’s d effect size=1.01). The observation that PFC-tDCS during learning can boost verbal episodic memory in the elderly opens up the possibility to design specific neurorehabilitation protocols targeted to conditions that affect episodic memory such as MCI.
Improved working memory is why many of us are interested in tDCS. Here’s another study showing no effect. Looks like a good study, though it’s a single-session of tDCS. Of late I’ve noticed more studies targeting working memory using the N-back test to measure. I’m hopeful a protocol will be discovered (i.e. a different montage, dosage, or perhaps tACS) that does improve working memory.
Transcranial direct current stimulation (tDCS) has been put forward as a non-pharmacological alternative for alleviating cognitive decline in old age. Although results have shown some promise, little is known about the optimal stimulation parameters for modulation in the cognitive domain. In this study, the effects of tDCS over the dorsolateral prefrontal cortex (dlPFC) on working memory performance were investigated in thirty older adults. An N-back task assessed working memory before, during and after anodal tDCS at a current strength of 1mA and 2mA, in addition to sham stimulation. The study used a single-blind, cross-over design. The results revealed no significant effect of tDCS on accuracy or response times during or after stimulation, for any of the current strengths. These results suggest that a single session of tDCS over the dlPFC is unlikely to improve working memory, as assessed by an N-back task, in old age.
Many of the leading tDCS researchers contribute to this Open Access article on clinical application of transcranial electrical stimulation (tES) techniques. Read it online, or download the pdf. (HatTip to Reddit user gi67)
- 1. Introduction
- 2. Transcranial direct current stimulation
- 2.1. Selecting and preparing electrodes and contact medium
- 2.2. Selecting and preparing electrode placement
- 2.3. Selecting a stimulation protocol
- 2.4. Use of blinding and sham
- 2.5. Safety versus tolerability
- 2.6. Considerations for transcutaneous spinal DC stimulation (tsDCS)
- 2.7. Considerations for cerebellar tDCS
- 2.8. Selecting a stimulator
- 3. Transcranial alternating current stimulation (tACS)
- 4. Monitoring physiological effects of tES
- 4.1. Monitoring physiological effects of tES with TMS
- 4.2. Monitoring physiological effects of tES with electroencephalography (EEG) and event-related potentials (ERPs)
- 4.3. Monitoring physiological effects of tES with magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS)
- 5. Monitoring functional effects of tES
- 6. tDCS/tACS/tRNS in animal preparations
- 7. tDCS and models of electric current through the brain
- 8. tES ethics
- 9. Concluding remarks
The analysis also found that women who were prescribed more than one class of antidepressants during the last six months of pregnancy were more than four times more likely to have a child with autism, compared with women who did not take antidepressants while pregnant.
Update 10/16/2015: Today I learned that this study is ongoing and recruiting participants. If you or someone you know is pregnant and dealing with severe depression, consider contacting study author Simone Vigod at Women’s College Hospital in Toronto. Study Protocol. You can also follow Simone on Twitter.
Tatania Samburova, a Russia-born economist who immigrated to Canada two years ago, developed depression before becoming pregnant. Her depression left her feeling hollow, even suicidal.
“You do not feel yourself living. You do not want anything, you do not want to go somewhere, to do something,” she said.
Her doctor offered her antidepressants, but, while she knew they would offer her relief, she decided against using them over fears they may harm her child.
“Even if it will bring me, right now, some kind of relief, it can also affect the life of a little child,” she said.
Instead, she travelled to Mount Sinai (hospital) every day for three weeks to be treated as part of the study. She doesn’t know for sure if she received a sham treatment or the actual tDCT stimulation but suspects she had the actual therapy because within days her appetite returned and she felt her mood lifting.
“This treatment brought happiness back to me; it brought life back to me,” she said.
She remains well today, with her baby due mid-March.
Vigod notes that some women are so desperate for treatment that they are not waiting for the study results.
“I can tell you anecdotally that women are buying devices like this in the U.S. and using them at home, but they haven’t really been tested to see if it works to make the depression better.”
From the study protocol: The active tDCS intervention is active 2 mA tDCS. Direct current is transferred continuously for 30 minutes with a pair of saline-soaked sponge electrodes (contact area of 5 × 7 cm), and delivered by a specially developed, battery-driven constant current stimulator. The electrodes are placed over F3 and F4 according to the 10–20 international system for electroencephalogram placement.
From a study published earlier this year that collected responses from 265 career scientists whose work involves tDCS.
Researchers’ perspectives on scientific and ethical issues with transcranial direct current stimulation: An international survey
The cautious approach to use of tDCS is also reflected in the low ratings for efficacy of its use to enhance normal functions. The tDCS research community appears well aware of current limitations and the need for future research to address those. The appearance of enthusiastic articles in the media and online suggest that these cautious views are frequently not being communicated clearly to the public. Researchers must make their views about the limited evidence of safety and efficacy clearly when speaking with the media or communicating with the public.
Using transcranial direct current stimulation, we tested whether stimulation of left lateral prefrontal cortex had discriminate effects on language and memory conditions that rely on executive-control (versus cases with minimal executive-control demands, even in the face of task difficulty). Participants were randomly assigned to receive Anodal, Cathodal, or Sham stimulation of left lateral prefrontal cortex while they (1) processed ambiguous and unambiguous sentences in a word-by-word self-paced reading task and (2) performed an n-back memory task that, on some trials, contained interference lure items reputed to require executive-control. Across both tasks, we parametrically manipulated executive-control demands and task difficulty. Our results revealed that the Anodal group outperformed the remaining groups on (1) the sentence processing conditions requiring executive-control, and (2) only the most complex n-back conditions, regardless of executive-control demands. Together, these findings add to the mounting evidence for the selective causal role of left lateral prefrontal cortex for executive-control tasks in the language domain. Moreover, we provide the first evidence suggesting that brain stimulation is a promising method to mitigate processing demands encountered during online sentence processing.
This is an incredibly well-researched paper. All the nuance of FDA regulation around tDCS and similar devices is made clear. I’ve been picking away at trying to understand this myself, but had become extremely frustrated by the complexity and opacity of FDA jargon and legalese. Anna has collected all the relevant facts and applied them very close to home citing specific devices and situations the DIY tDCS crowd will be familiar with. Anna Wexler is the author as well of The practices of do-it-yourself brain stimulation: implications for ethical considerations and regulatory proposals (gated) . She spoke to myself and at least a handful of other reddit.com/r/tDCS contributors for that paper. In both papers she lays out a very sensible approach to regulating tDCS, or rather, not regulating it. Stating that there is already a body of relevant law stemming from various government agencies (in the U.S.) that could be called upon to regulate tDCS device use as needed.
This paper contributes to the literature on the regulation of consumer brain stimulation devices in the USA by providing a fact-based analysis of the consumer tDCS market and relevant laws and regulations. In the first section, I present a short history of the DIY tDCS movement and the subsequent emergence of DTC devices. In the second and third sections, I outline the basics of FDA medical device regulation and discuss how the definition of a medical device—which focuses on the intended use of the device rather than its mechanism of action—is of paramount importance for discussions of consumer tDCS device regulation. I then discuss how both the FDA and the courts have understood the FDA’s jurisdiction over medical devices in cases where the meaning of ‘intended use’ has been challenged. In the fourth section, I analyse the only instance of tDCS regulatory action to date, in which the California Department of Public Health (CDPH) forced a firm to recall several hundred consumer tDCS devices. Although there exists a common perception that the FDA has not been involved with the regulation of consumer tDCS devices, the California case demonstrates that the CDPH’s actions were instigated by an FDA engineer. Finally, I discuss the multiple US authorities, other than the FDA, that can regulate consumer brain stimulation devices.
|CONSUMER TDCS DEVICE||MARKETING LANGUAGE|
|Brain Stimulator* https://thebrainstimulator.net/what-is-tdcs/||‘tDCS allows you to unlock your brain’s true potential’|
|Cognitive Kit* http://www.cognitivekit.com/||‘Charge your mind’|
|tdcs-kit http://www.tdcs-kit.com/||‘Power your mind’|
|ApeX Type A* http://www.apexdevice.net/||‘Be happier. Be focused. Be smarter’|
|Foc.us* http://www.foc.us/||‘make your synapses fire faster’, ‘overclock your brain’, ‘take charge’|
|Thync* http://www.thync.com||‘quiet your mind’, ‘boost your workout’|
|PriorMind http://www.priormind.com||‘increase your attention span’ ‘tDCS has been widely used to treat depression…’|
|TCT* http://www.trans-cranial.com||‘when only the best in tDCS therapy will do’|
|Super Specific Devices* http://www.superspecificdevices.com||‘personal tDCS device’|
*Website contains some form of a medical or health-related disclaimer.
Oxley said a paper published in Nature last year, which showed lucid dreams could be induced through stimulating gamma waves in a sleeping person, inspired a lot of customers to try to use foc.us in the same way. So the foc.us team wrote a new program specifically designed to try to ellicit lucid dreams.
“A positive charge will excite a part of the brain and a negative current will sort of turn off that part of the brain,” Oxley said. “The higher function areas at the front of the brain are active during lucid dreams, so the idea is that if we excite that while people are dreaming, they’ll have a greater chance of having a lucid dream.”
Oxley said he uses the device nearly every night, and while it doesn’t always work, when it does it’s very exciting. Unfortunately, my experience was not quite so thrilling. Though the lucid dream program on the foc.us delivers a relatively low electrical current of 1.5 milliamps, it was too high for me. The electrodes immediately started to sting my skin and I had to take them off after about three seconds. So, I enlisted my less-sensitive coworkers to test it out, but the results were just as disappointing.
Indirectly related to tDCS but a fascinating new paper attempts to understand how the frontal cortex is responsible for cognitive control.
“Surprisingly,” Bassett said, “our results suggest that the human brain resembles a flock of birds. The flock comes to a consensus about which way to fly based on how close the birds are to one another and in what formation. Birds that fly at specific places in the flock can drive changes in the flock’s direction, being leaders in a so-called multi-agent system.
“We’re very interested in controlling brain networks with techniques like optogenetics, transcranial magnetic or direct-current stimulation, deep brain stimulation or even neurofeedback,” Bassett said, “but the problem has been that there is little theoretical basis to determine how these stimulations affect the dynamics of the whole brain. In most cases, stimulation is applied via trial and error. This research helps to build up an understanding of the impact of stimulation in one region on cognition as a whole.”
Future research will test whether “wiring” differences between people predict their performance on cognitive tasks. It will also underpin work on therapeutic and adaptive technologies that capitalize on brain networks’ unique advantages over their computerized counterparts.
Huge Flock of Starlings Caught on Film (Hereford, UK 2014)
At 20:40 Katie Witkiewitz begins discussing the use of tDCS as a tool for enhancing mindfulness training. Her work is mostly focused around addiction and recovery. She compares her own experience of using tDCS-assisted meditation to day 4 of a multi-day meditation retreat. They are using the anode F10 / cathode left shoulder (“Where’s Waldo” DARPA research) montage. There’s a shot of what she calls the ‘octa box’ which seems to be distributing current from a single ActivaDose device to 8 sets of electrodes for ‘group mindfulness training’ (but I could be wrong). Could tDCS enhance your meditation? Provide that extra bit of calming the chatter? She goes on to say that (including her own personal experience) the montage ‘inhibits verbal ability’ and that trying to lead a guided meditation while stimulating F-10 gave her ‘the worst headache’.