tDCS and Tinnitus

Reader Patty asked if there were reports of tDCS being effective in the treatment of tinnitus. As this is an important issue to me as well, I thought I’d collect whatever related links I have to the research in one place. While the results I’ve read here seem inconclusive, if I were one of the 3% of tinnitus sufferers for whom the constant sound is extremely disturbing, I wouldn’t hesitate to try one of the protocols outlined in these studies. If you have information to share about your own experiences with tDCS and tinnitus please post them in a comment.



tDCS – the bigger picture | Body in Mind

Kerstin Luedtke

Kerstin Luedtke

Things have moved on from there and luckily we now have a randomised controlled trial with a sufficient sample size (n=135) of patients suffering from chronic low back pain and shown that tDCS – at least in this population and using a paradigm of 2mA for 20 mins on 5 consecutive days over the motor cortex – does nothing to reduce the perceived intensity of back pain or the disability associated with chronic low back pain (Luedtke et al., 2015). The results were not only not statistically significant, there wasn’t even a trend into the right direction

Source: tDCS – the bigger picture – Body in Mind

Researchers’ perspectives on scientific and ethical issues with transcranial direct current stimulation: An international survey : Scientific Reports : Nature Publishing Group

The largest proportion of researchers rated tDCS in research contexts (cognition, motor, affect) as “partly effective” (28-42%) or “mostly effective” (19-33%). Only a small percentage described tDCS as “ineffective” (2-5%) or “absolutely effective” (2-13%; Fig. 1A). Effectiveness ratings were highest for the motor domain (N = 213, mean±SD 1.71 ± 0.77) followed by cognition (N = 218, 1.49 ± 0.69) and affect (N = 143, 1.34 ± 0.68).

Source: Researchers’ perspectives on scientific and ethical issues with transcranial direct current stimulation: An international survey : Scientific Reports : Nature Publishing Group
via: @mancini_flavia

The Maverick of Brain Optimization

Tim Ferris interviews Dr. Adam Gazzaley of the Gazzaley Lab at UC San Francisco.

His recent studies go far beyond mere description — he and his lab are exploring neuroplasticity and how we can optimize cognitive abilities, even in healthy adults. So, what happens when you combine cognitive-focused video games with neurofeedback, magnetic and electrical stimulation, and even performance-enhancing drugs? Well, that’s just one of many things we cover in this conversation

See Also:
Lots more media from the Gazzaley Lab here:

An Evening with the Consciousness Hackers | The New Yorker

For the evening’s first demonstration, Siegel helped attach electrodes to the temples of Adam Goyer, a volunteer test subject, then cued Eugene Sinkevich, an electrical engineer, to start the current. “We are at the frontier,” Siegel said, looking out at the crowd as no more than two milliamps ran through Goyer’s head. “We’ll be able to tell our kids that we used to hook up arbitrary electrical signals to our brain.”Goyer sat still for several minutes, flinching only slightly. Then it was over. How did he feel?“First, let me say I’m really nervous about putting electricity through my brain. The first wave felt like a tingling on my forehead, and I guess I’m smarter afterward, sure. Then the second wave of tACS [transcranial alternating-current stimulation, a type of stimulation in which the flow of the charge varies] I kinda felt woozy, not in a bad way, but kind of like I’m on a boat. Then the third one, I definitely had some flickering, some eye flickering: in the outside of your eyes it’s like a flash, like a strobe.”

Source: An Evening with the Consciousness Hackers – The New Yorker

The benefits of mind-wandering |

The scientists also used “transcranial direct current stimulation,” in which an electrode is attached to the scalp, sending low electrical currents that activate neurons directly underneath. Electrodes were positioned over the dlPFC (or, for a control group, over an unrelated brain region) and turned on or off during the repetitive task. (Importantly, subjects typically couldn’t detect the current.)

The result? Stimulating the dlPFC increased the amount of mind-wandering. And did performance on the task plummet? No; it even improved a smidgen.

What does it mean that this hard-nosed, task-oriented, executive brain region helps to mediate mind-wandering? Why should the dlPFC want us to daydream? Probably because it can be beneficial.

For starters, mind-wandering fosters creative problem solving. It also aids decision-making by allowing you to run future-oriented simulations in your head: “Hmm, so how might things be if I decide to do X? How about if I do Y?” It’s ideal not just for thinking about possible outcomes but also for thinking about how different outcomes would feel.

Source: The benefits of mind-wandering
Study: Increasing propensity to mind-wander with transcranial direct current stimulation

Hooking up: zapping your brain

Katie, 23, has suffered from anxiety and depression since she was 18. When her boyfriend Lee told her about transcranial directcurrent stimulation (tDCS), a form of neurostimulation which involves administering a low level of electrical current to the brain, she was sceptical. But Lee had heard that it could help people with mood disorders and wondered if she might benefit from it.

“The first time, I freaked out,” she remembers. “I thought, ‘I can’t cope with putting electrical stimulations in my brain.’ Lee put this machine on and, it’s difficult to explain, but, everything went empty in a good way. I can’t remember if I’ve ever felt like that. I felt relaxed and chilled inside. It was a mad sensation and an out-of-body experience.”

She’d tried anti-depressants in the past but found they didn’t work for her. Now she uses the kit regularly. “It’s improved my life and improved my mind,” she says.

Source: Hooking up: zapping your brain

Noninvasive brain stimulator may ease Parkinson’s symptoms | JHU

The students were referred to Yousef Salimpour, a Johns Hopkins Medicine postdoctoral research associate who has been studying a noninvasive Parkinson’s therapy called transcranial direct current stimulation. In this painless treatment, low-level current is passed through two electrodes placed over the head to tweak the electrical activity in specific areas of the brain. The technique can be used to excite or inhibit these nerve cells. The treatment is still considered experimental, but it has attracted much attention because it does not require surgery and is inexpensive, safe and relatively easy to administer without any side effects.


Transcranial direct current stimulation: before, during, or after motor training?

The ‘online’ (stimulation during training) vs. ‘offline’ (stimulation prior to or after training) question is addressed here in this study I only have the abstract for. But in this case “These data suggest that tDCS performed before – not during or after – promotes optimization of motor training-induced plasticity.” Keep in mind that, there are many (montage, kind of test/training) variables and that other studies have shown advantages to online training.

Noninvasive brain stimulation has recently been used to augment motor training-induced plasticity. However, the exact time during which noninvasive brain stimulation can be combined with motor therapy to maximize neuroplasticity and behavioral changes is unknown. We conducted a randomized sham-controlled crossover trial to examine when (before, during, or after training) transcranial direct current stimulation (tDCS) should be applied to best reinforce motor training-induced plasticity in 12 healthy right-handed participants (mean age: 21.8±1.6) who underwent active or sham tDCS combined with motor training. Transcranial magnetic stimulation-elicited motor-evoked potentials from the right first dorsal interosseous muscle were recorded before (baseline) and immediately after each session. The training task comprised four practice trials – 3 min each (30 s pause between trials) – of repetitive finger movements (thumb abduction/adduction) with the right hand. Anodal tDCS (1 mA, 13 min, on the motor primary cortex) was applied before, during, and after the training. Compared with baseline motor-evoked potentials and the sham condition, tDCS that was applied before, but not during or after, the motor task enhanced corticospinal excitability. These data suggest that tDCS performed before – not during or after – promotes optimization of motor training-induced plasticity.

Early adopters of the magical thinking cap: a study on do-it-yourself (DIY) transcranial direct current stimulation (tDCS) user community

Well done! Anita Jwa’s study of the DIY tDCS community is published. I would think this very useful to policy makers. I was only surprised by a few of her findings. Links below to full paper.

This study is the first empirical attempt to investigate the DIY tDCS user community. A questionnaire survey of DIY users, interviews with some active power users, and a content analysis of web postings on tDCS showed distinctive demographic characteristics of the DIY users, ambiguities and mistaken assumptions around the current state and future prospects of the DIY use of tDCS, mixed use of tDCS for both treatment and cognitive enhancement, the existence of an active self-regulating system in the community, and users’ demands for official guidelines and their concerns about government regulations on tDCS.

Source: Early adopters of the magical thinking cap: a study on do-it-yourself (DIY) transcranial direct current stimulation (tDCS) user community

Brain Stimulation and Imaging Meeting June 12-13 2015

Some very interesting abstracts coming out around the upcoming BrainStim conference.

Dr. Giulio Ruffini, “Transcranial Current Stimulation: Going Multifocal”
“…I will describe a new class of devices using multi electrode montages and small, EEG-compatible electrodes, complemented by advanced biophysical models.”

Dr. Marom Bikson, “Targeting transcranial Electrical Stimulation using EEG: The scalp space approach”
“…Next, how to optimize tES based on either evoked or spontaneous EEG recording is discussed including a novel “scalp space” approach which requires no source localization and no computational modeling.”

I see also that the The Neuroelectrics Team will be demonstrating their “latest wireless EEG (Enobio) and tCS (StarStim) technology as well as our latest StarStim Research Home Kit.

Scientists retrieve lost memories using optogenetics

I’m exposing my bias here, which is the hope that tDCS will be found to facilitate memory retrieval. This study, in mice, retrieved dormant memories using light (optogenetics) to activate cells used in memory formation. Recent studies suggest that memories are formed within a synaptic network, parts of which extend to areas of the brain more frequently targeted by tDCS. Probably closest to the research I’d like to see done (that I’m aware of) was reported in 2009, “Where Are Old Memories Stored in the Brain?“. I imagine a study where early memory, triggered by photos and recollections, are imaged using fMRI and that later, those same areas are targeted using tDCS. In the study reported on above, Medial Temporal Lobe Activity during Retrieval of Semantic Memory Is Related to the Age of the Memory, researchers concluded that older memories associated with regions in the frontal lobe, temporal lobe, and parietal lobe. (Though seems inconclusive as to whether memories are ‘stored’ there… “An additional way to understand the increasing involvement of some cortical areas, especially frontal cortex, as time passes is that older memories require more strategic, effortful search.”) Now, back to the post title article…

The researchers then attempted to discover what happens to memories without this consolidation process. By administering a compound called anisomycin, which blocks protein synthesis within neurons, immediately after mice had formed a new memory, the researchers were able to prevent the synapses from strengthening.

When they returned one day later and attempted to reactivate the memory using an emotional trigger, they could find no trace of it. “So even though the engram cells are there, without protein synthesis those cell synapses are not strengthened, and the memory is lost,” Tonegawa says.

But startlingly, when the researchers then reactivated the protein synthesis-blocked engram cells using optogenetic tools, they found that the mice exhibited all the signs of recalling the memory in full.

“If you test memory recall with natural recall triggers in an anisomycin-treated animal, it will be amnesiac, you cannot induce memory recall,” Tonegawa says. “But if you go directly to the putative engram-bearing cells and activate them with light, you can restore the memory, despite the fact that there has been no LTP.”

Source: Scientists retrieve lost memories using optogenetics
See Also: Neuroanatomy of memory
Gone But Not Forgotten? The Mystery Behind Infant Memories
The Hippocampus and episodic memory
Neuron Basics (video)

Time to Take Another Look At tDCS and more | SpeakWisdom

It’s a Software World Now!
If you purchase a V2 (or own one now), you may wish to update its firmware periodically to take advantage of new features. Here are some key steps:

  1. Go to the web site and create an account:
  2. Log in with the account
  3. Connect your V2 doc to your capable PC (or Mac)
  4. On the left of your screen (once logged in), select “My Downloadable Products”
  5. Click the “Microsoft Software” (or Mac) download button and install
  6. Run the installed application and allow it to check and upgrade your V2 to the latest firmware

Source: Time to Take Another Look At tDCS and more | SpeakWisdom