Transcranial Direct Current Stimulation!

I recently attended a Quantified Self meetup at the Microsoft NERD center in Kendall. It was very well organized — thanks to Joshua Kotfila and Maggie Delano. Hopefully future meetups have more people presenting!

The event consists of two main parts — a pre-talk social session and a series of talks. There were a few people and companies showing off their projects before the talk.

One of the groups showing before the talk was a company called Thync. They are attempting to bring a Trans-cranial Direct Current Stimulation (TDCS) device to the market. TDCS has been shown in a number of studies to have positive effects on learning — language learning if I recall correctly. It’s also supposedly safe. They were offering demonstrations of their new device at the event.

TDCS requires making two electrical contacts to your head. The 15 minute “relaxation” session required one contact to your temple and one to the back of your neck. They use a modulated current source of about 2mA to excite certain portions of the brain. During the 15 minutes, I noticed a few things:

  • It’s important to have the electrode tightly affixed to your head, otherwise it’s quite tingly and uncomfortable.
  • It was a bit difficult to talk at first.
  • I noticed a distinct metal taste in my mouth — very similar to the sensation of licking a 9V battery. The engineer that I was talking to said that could have something to do with the electrode material. I’m a bit skeptical of that since the electrodes were both a long distance away from my mouth. Lowering the intensity made this less noticeable.
  • There was a bit of noise in my ear — apparently the waveforms that are used have a component in the higher frequency audio range. I noticed a ringing around 10kHz or so.
  • My neck started to cramp up towards the end of the session.

In a single session, I can’t say that I felt any more relaxed at the end of the fifteen minutes than I would have if I was just sitting in the same comfortable chair. I had just come in from a client site and walked a good distance in the cold before arriving in the nice warm NERD center. I think that any relaxation effect was swamped by my coming off of work and going to an event that I was interested in. More than a single session would be necessary to show it’s effectiveness (or ineffectiveness). They electrodes they were demoing worked pretty well. They were definitely nicer than the ones that my Zeo was using.

In summary - I definitely felt something, but I’m not sure that it was what was intended. More research is definitely needed on my part.