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This is a page skeleton for some new projects we're going to document here! Feel free to fill shit in. --Hurtstotouchfire 21:16, 7 May 2012 (UTC)


[edit] Transcranial Direct Current Stimulation

Wikipedia, bitches. For the record, the acronyms tDCS and TDCS are both in use in academia, and I think the former is stupid because they're just trying to be cool like iPhones and fMRI. The word transcranial is obviously abbreviated, and when we abbreviate words in an acronym, we capitalize them. So if you move this page to tDCS, I will move it back. --Hurtstotouchfire 01:14, 12 May 2012 (UTC)

[edit] Academic publications

The best collection of academic study abstracts is here. (note that we should snatch this and put a copy somewhere, since we have no clue who this dropbox account belongs to or how long access will stay stable. The file has credit within, so I don't think it's evil. I will try to remember to email the creator and make sure he has no issues with same) - JPW

There are quite a few other abstracts from more recent work that aren't included here, including the stuff from the most recent big neuro yearly powwow in DC. (Kelly, do you still have the links to those papers from the military guys at Wright-Patterson?) - JPW

I have no crapping idea. --Hurtstotouchfire 01:14, 12 May 2012 (UTC)
Year Journal Title Results Anode Cathode Link
2011 Stroke Short-term anomia training and electrical brain stimulation Anodal transcranial direct current stimulation applied over the nonlanguage dominant hemisphere can enhance language training outcome in chronic aphasia. R-TPJ (Right temporal parietal junction) Unclear
2011 Neuriobiol Aging Non-invasive brain stimulation improves object-location learning in the elderly. improved recall 1 week after learning with anodal tDCS R-TPJ (Right temporal parietal junction) Unclear
2011 Clin Neurophysiol Improving working memory: Exploring the effect of transcranial random noise stimulation and transcranial direct current stimulation on the dorsolateral prefrontal cortex. Anodal tDCS increased working memory DLPFC (Dorsolateral prefrontal cortex) Unclear
2011 Neuroimage Modulating inhibitory control with direct current stimulation of the superior medial frontal cortex. anodal tDCS improved efficiency of inhibitory control, useful for ADHD/ADD Pre SMA (prefrontal) unclear
2011 J Neurophys Probing for hemispheric specialization for motor skill learning: a transcranial direct current stimulation study. Left M1 tDCS induced significantly greater skill learning L/R M1
2011 Neuroscience Transcranial direct current stimulation over Broca's region improves phonemic and semantic fluency in healthy individuals. These data confirm the efficacy of tDCS in transiently improving language functions by showing that anodal stimulation of Broca's region can enhance verbal fluency. Broca's (assuming left) Unclear
2011 J Neur Short- and long-lasting tinnitus relief induced by transcranial direct current stimulation. Has effects, lasting days sometimes, but worsened tinnitus in some Left Temporoparietal (and reverse) Unclear
2011 Exp Transl Stroke Med Effect of a tDCS electrode montage on implicit motor sequence learning in healthy subjects. tDCS led to greater consolidation of the learned motor sequence than sham stimulation Motor cortex (tested uni and bilateral montage) Contralateral M1 or unclear
2011 Brain Stimulation Improving working memory: the effect of combining cognitive activity and anodal transcranial direct current stimulation to the left dorsolateral prefrontal cortex. tDCS applied during completion of the n-back task was found to result in greater improvement in performance on digit span forward, compared with tDCS applied while at rest and sham tDCS during the n-back task. L-DLPFC Unclear

[edit] Anecdotes

TDCS subreddit Note that this source of information is wildly inconsistent. While a few people there are fairly well educated on the subject, a huge amount of outright misinformation lives and breeds there. judas 08:47, 25 October 2012 (UTC)

[edit] Spec

The basic circuit for TDCS is ridiculously simple. We are creating a 2ma DC current and running it through 2 inch square or round electrodes that are then connected to the human body. There are various configurations that can be used to place the pads, but the most common is placing the active electrode over the area of the skull corresponding to the brain region to be effected and the other electrode, called the return electrode, is placed on the opposite shoulder. Using the anode, or positive electrode, over the brain will stimulate the target region. The cathode, or negative electrode, will retard the brain region. A standard simulation time in most research is 20 minute sessions. The effect, depending on the type of stimulation and region seems to last up to an hour after the stimulation is removed. Again, depending on the type and location of the stimulation, repeated exposure daily for up to 9 sessions can cause the effects to persist for 30 days or longer in depression studies.

The simplest working circuit for this is a pair of 9v batteries in series, an LM334 current limiter and a fixed resistor across the LM334 reference and output to set the 2ma limit. A better circuit involves replacing the fixed resistor with a 200 ohm pot and adding an ammeter anywhere in series. One of the better designs of this nature is located here. Although the fuse in the circuit is of unlikely utility in reality.

A fairly simple, slightly unsafe and highly voltage limited arduino project that is somewhat clever is located here.

The cadillac of designs here would probably look something like an arduino controlling a SPI variable resistor connected to an LM334 for current control, another LM334 with a fixed resistor to provide failure protection (a fuse is going to blow too slowly and fuses that small are expensive and difficult to source), a shunt ammeter connected back to the Arduino and a display/input to allow the user to set different times, current levels, sham stimulation and so on. Also we would want to put a boost transformer on the battery supply in order to boost the output voltage being used. Discussion of why we want to up the voltage here will happen in the section on electrodes.

(need to add a long discussion about electrodes here, since there is more complexity in the electrodes than the circuit itself)

[edit] Montages

This is a placeholder to keep track of different montages people are using, and their results.

One way to standardize our results could be some sort of cognitive test. The RACE assessment seems useful: But different people will of course be looking for various measures of "improvement". Feel free to add more.

RACE results Anode Cathode Current Stimulation time Electrodes used Device design

[edit] Other Resources

  • link to that great website with the videos.
  • anyone else have spec online?
  • Journalist becomes a hardened killing machine on TDCS.

Circuit designs

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