Tag Archives: frontal lobe

A slump and a new tDCS montage

Over the last few months I haven’t updated this blog – I have had a slump, which left me somewhat unmotivated about self-improvement and other activities that aren’t central to staying afloat. In the end what shook me out of it was an overseas trip. Jet lags force one to look at things in a new light, waking up at unfamiliar hours, or staying up late without a hint of tiredness.

Still, about the time when I got back, I heard of an interesting new montage mentioned on the /r/tdcs subreddit. It is called a fronto-occipital, or F-O depression montage, and involves placing the anode over Fp1, and the cathode over Oz.

Here is an abstract of a paper detailing this montage. It showed a lot of promise, and the activation of the DLPFC was observed to be even higher than with the most popular bifrontal montage.

Some other data also popped up that made this montage extremely interesting. It would seem, based on animal testing, that the habenula (pineal gland) plays an important role in motivation for both bodily exercise, and the pursuit of pleasurable activities. Of course, being deep inside the brain, targeted stimulation of the habenula is all but impossible without invasive (surgical) techniques, but a front-to-back montage, which directly affects much of the brain, might likely impart some effect to such deep-seated areas as well.

I tried the montage, with a 3×3 inch electrode over Fp1, and a large, 3.5×7 inch one draped horizontally over the occipital lobe – I wanted to avoid creating a cathodal hotspot over the occipital lobe. So far, it seems extremely rewarding. I did notice a significant alleviation of passive behavioral patterns, and an improvement in my mood. Applying tDCS in the morning, as opposed to the afternoon was also a welcome change – it is definitely the superior option, and the jetlag made it a lot easier than it would normally be.

My plan is to keep at it for 7 days, and write about my observations afterwards.


Casual use of tDCS

As I’ve mentioned in previous posts, I have some pretty good experience with tDCS. I’ll try to quickly go through the protocols I’ve been using, and my experiences.

First experiment

When I first applied tDCS, it was in the middle of a depressive episode with strange behavioral blocks. Such as, I’ve had this inexplicable dread of checking my mail, been unwilling to start or do anything productive, and similar. I have no idea about the exact neuropsychology of it (it would have been interesting to check myself with a QEEG unit if I had one), but I suppose it was some kind of over-inhibition. It’s something that’s characteristic of my basic “personality”, and something that’s caused me much grief in the past.

I applied tDCS in a bifrontal configuration with the anode over F3 (left dlPfC) and the cathode over Fp2 (right supraorbital). This is an extremely widely researched and proven configuration for treating depression, and is associated with increased conscious control over emotions and an improvement of executive functions including short term memory.

A great overview of tDCS montages and their observed effects in experiments is the TDCS State of the Art paper. Another awesome resource everyone should read are the manuals from Trans Cranial Technologies. They have a comprehensive, easy-to-understand manual on the 10-20 QEEG positioning system, proven tDCS montages, and on cortical functions for those who want to experiment with new setups.

The device was extremely simple, consisting of nothing but an array of CRDs (totaling 2.0mA) and a 1k resistor to suppress current spikes. As a bonus I managed to be the idiot I mentioned earlier, and connected my head last to a powered-up loop, so it can be said without doubt that the total current clearly has gone above 2.0mA upon turn-on (which manifested in a weird popping sensation and a feeling of electric shock – though no phosphenes).

The behavioral-cognitive effect was quite noticeable, but I still don’t know if it had more to do with the tDCS or the shock from the transients. Anyway, the behavioral blocks I mentioned were gone in about 5 minutes, and I soon caught up with all the stuff I have been putting off for days or weeks. In total I did 20 minutes of treatment, and disconnected. Upon disconnection, I experienced phosphenes. While from a subjective standpoint I’ve been successful, I decided to put off further experimentation until I’ve built a more secure device.

Following up

Later, when I completed the device described in previous posts, I decided to do a 5-day treatment regimen, using the same bifrontal configuration. This time, I always used the manual start/stop pot, and thus avoided any form of transient.

At this point I was not in any particularly bad condition psychologically (apart from a slight slump in motivation), and thus the effects of this treatment were barely noticeable from a subjective standpoint. I did observe a slight “emotional desensitization”, or increased control over my emotional responses. In a kind of Vulcan-ish way.

The treatment markedly did not help with my lack of motivation, which culminated in spending an entire weekend doing literally nothing but watching Game of Thrones. (In a rather positive mood, but that hardly counts in favor.) So it must be said that tDCS is not a magic bullet. It’s a “hardware level” tuning, and will not necessarily alleviate cognitive, “software level” problems.

A walk in the woods

I did a search over the net looking for ways to increase motivation via tDCS. What I did find was a montage based on anodal stimulation of the right dlPfC (F4), supported by some anecdotal evidence, and unsupported by experimental data. The one relevant experiment I found that used this setup failed to provide statistical data to support its effect on goal-oriented behavior. (That said, the failure might be attributed to a bad choice of measurement task, so I didn’t dismiss it out of hand.)

The protocol was 25 minutes daily for 3 days, using 2mA of total current between the anode over F4 and cathode over Fp1. Though there were no studies showing the effectiveness of this montage for motivation or goal-oriented behavior, it was proven to be without negative effects, and was being researched for alleviating alcohol and drug cravings, so I wasn’t particularly worried.

I did notice some reduction in the compulsive-repetitive behavior that is inherent to my genetic condition (there might be a link with the addictological effects of the montage), and slightly better goal-oriented planning, but nothing particularly striking, so I cannot rule out placebo effect. This slight improvement seems to have dissipated after discontinuing the regimen, though.

Refining the depression montage

I have had some worries about the bifrontal setup, as it has both the anode and cathode over areas of the frontal lobe. Later, I found some data supporting the use of an extracranial cathode. In this setup, the anode is placed over the left dlPfC (F3), and the cathode over the contralateral (right) arm.

I’ve done one 5-day regimen using this since, and I have recently started another. It does seem to help a lot – though I haven’t noticed such marked effects as the first experiment, that may also be because I haven’t experienced such marked behavioral blocks since. It’s hard to pinpoint the effect of treatment, but it’s definitely a thing. It’s not really what “is” there, but what “isn’t”. I definitely feel better and more productive when I’m using tDCS.

The tDCS craze

One of the reasons I started this blog was that I’ve recently learned about, and started experimenting with tDCS (transcranial direct current stimulation). I first read about it in the Wired magazine, which was of course full of journalistic exaggeration, but the idea really made my head spin.

In tDCS, the brain is stimulated with an extremely weak (1-2 mA total) stream of direct current. This is not enough to fire neurons, but seems to have an effect on action potentials, and the neuroplasticity of the brain areas the current passes through. In clinical research, tDCS has been successfully used to alleviate depression, and to improve chances of recovery after brain damage.

The journalistic hysteria was, however, centered on another claim that researchers were making. That tDCS has the potential of improving cognition and learning ability in healthy humans – while being completely safe, as far as researchers can tell. The phrase of “putting one’s thinking cap on” has suddenly become quite literal.

That’s interesting in a way, but what really made this a breakthrough was the simplicity of the hardware required. There is no need for high voltage like in magnetic stimulation (TMS), or complex software. A simple low power current source and a pair of medical electrodes is all that is needed to replicate 95% of the clinical experiments. And thanks to this, a serious community of DIYers has sprung up.

While there are reckless idiots as anywhere else (some have taken a 9V battery, and connected it to their heads), most of the community is made up of responsible, yet adventurous people – some are transhumanists out for the cognitive boost, some are looking to alleviate their depressive symptoms – and it seems to boast a pretty good rate of anecdotal success. This has resulted in the start of a cautious conversation between professional researchers and the community.

tDCS device

Drawn to the idea, I’ve also built a device. For one, I’ve been having trouble with a low-key manic depressive tendency, and also I was wondering if this could be used to address the frontal lobe inactivity problems inherent to my genetic condition.
While I don’t have a too long history to share, so far it seems I’ve both successfully reduced the amount of compulsive repetitive behaviors, and cut a depressive episode short.

In future posts I’ll be writing in detail about the device design, where it came from, and why I decided on building it like this. I’ll also be addressing the electrode montages I’ve been using, and maybe add some subjective updates of my experiment.

In the meantime, I think the best resources to read for general curiosity are the /r/tDCS FAQ and this SpeakWisdom article about depression treatment.