The TCDS device used in my experiments is described here-> https://www.youtube.com/watch?v=d9iId0Aen2g

If you are experimenting with DIY TDCS, obviously, the first thing you will want to know about is where to place the electrodes on your skull, and, if using monopolar techniques, where the on your body the non-skull electrode should go.

This manual is the result of my searching through reams of real medical research to see what they did, and how things turned out.

It is very important for the reader to know I am not a doctor (I am an IT consultant), and I am offering no advice of my own.  Everything stated here is from other (referenced) sources.

A very good discussion group in the subjest is http://www.reddit.com/r/tDCS

The Basics.

The first thing you will need to know is the terminology that you will see.  There are three types of terminology we will use here:  10-20, Lobes and Cortex[1]

The International 10-20 System (of electrode placement) [2] .  

This is the ‘map’ used internationally to describe where electrodes are placed on the skull.  Here is the map (NASION is the front of the head, INION is the back).

673px-21_electrodes_of_International_10-20_system_for_EEG.svg.png

10-20_sys.gif

Lobes

The second terminology used is the names of the various parts of the ‘lobes’, and are also used to describe where, on the skull, the electrodes are placed to affect these parts of the brain.

The most general ‘lobe map’ looks like this:

human-brain.png

These areas are easily accessible as they connect directly with the skull.

Here is an overlay of the 10-20 map and the regional map.

1020C.gifareas.png

Cortex

The division of the brain by ‘cortex’ looks like this (by name and Broadman Name Area):

brodmann-areas-brain-cortex-en_medical512.jpg

Looking more inside the brain, we have other, less accessible areas…

Time.innerbrain.JPEG

Placement most common for TDCS

tdcs_placements.jpeg

tdcs_placements_side.jpeg

For more easy to understand maps of the brain, visit http://cognitrn.psych.indiana.edu/busey/Q301/BrainStructure.html

10-20 positioning manual -> http://www.trans-cranial.com/local/manuals/10_20_pos_man_v1_0_pdf.pdf

A more details map, which shows the popular point F10

http://static.wixstatic.com/media/cf0be0_266aacf5168346bb870b68342c75c302.jpg_srz_281_196_75_22_0.50_1.20_0.00_jpg_srz

looks like this

Terms

You will see labels like left DLPFC’.  This stands for “Left DorsoLateral PreFrontal Cortex”.  Looking at the Cortex map, we see that this translates to the F8 electrode location.

Other abbreviations you may see are:

FC = medial frontal cortex (Fz)

DLPFC = dorsolateral prefrontal cortex (F7 (left) & F8 (right)).

PFC = prefrontal cortex (Fp1 (left) & Fp2 (right))

etc...

You have two electrodes:

The Cathode

The cathode is a negative charge, also called the ‘return electrode’.

Cathodes are known to ‘hyperpolarize’ an area of the brain

Downregulation

Downregulation happens where cells become less sensitive to stimuli. These downregulated cells may be said to be “desensitized.  It appears that the cathode-side of the (bipolar) circuit downregulates that part of the brain.

        Cathodes decrease cortical activity by 10-30% [3]

The Anode

The anode is a positive charge, also called the ‘active electrode’.

Anodes are known to ‘depolarize’ an area of the brain.

Upregulation

Upregulation is a process that makes cells more responsive to stimuli.  It appears that the anode-side of the (bipolar) circuit (in bipolar circuits) upregulates that part of the bring.

Anodes increase cortical activity by 20-40%

The current moves from the anode to the cathode.  Where you place the anode and cathode determines the direction of the current.  This appears to be very important.

For example,  reversing the polarity on a montage that helps with depression can make you paranoid and sad.

Monopolar and Bipolar

A monopolar stimulation means one electrode (usually the anode) is place on the skull, and the cathode is place on the upper right or left arm.  In this configuration, the current can only flow into OR out of the brain, i.e. there is only downregulation OR upregulation of one part of the brain .  note: It is a good idea to keep all the cathodes above the line of the heart, as to not interfere with it’s electrical activity.

Bipolar stimulation is when both the anode and the cathode are placed on the brain, and the flow is both into AND out of the brain, i.e. there is downregulation of one part of the brain AND upregulation of another part of the brain.

Other very important assumptions

Whether you built your own TDCS device or bought it, we assume you will be working with power ranges in the .5 - 2 mA (milliAmps), and in general will keep your times of exposure to 20 minutes or less.

We also assume you will but will only be working on the surface of the skin ONLY (unlike the sailor, and winner of the the 1999 Darwin Awards, who stuck probes into his body, and promptly died[4])

We have looked for research that specifically uses a constant DC (Direct Current) that uses no waveforms, which are commonly used in brain stimulation and research.

Dangers

Although TDCS is non-invasive and considered quite safe, it is not 100% guaranteed to not be consequence-free.  There is still a lot of research being performed to better understand these consequences.  Do you own research.

Tips

A common placement point is the left DLPFC, but stimulating this area can also lead people to tend towards anger and aggression[5]


Depression Montage

Warning: Reversing the anode and cathode can tend to make one depressed, paranoid and generally miserable.

Anode / Cathode = F3 / F4

sm_f3-f4.png


The “Happy Buddha” Montage

This combines TDCS and meditation.  Place Anode at OZ and cathode at FpZ, and follow the meditration ast shown here -> https://www.youtube.com/watch?v=sz7cpV7ERsM

sm_oz_fz.png

The study is not the same as the one I use, I’ve tried both montages, and I personally found that the variation with cathode at FpZ works better in conjunction with meditation)[6]


Insight montage [7]

This montage seems to create insight into problem solving

Anode: right anterior temporal lobe (F8)

Cathode: left anterior temporal lobe (F7)

Time: 20 minutes

sm_f8-f7.png

it has also been claimed that stimulation of the Right Anterior Temporal Lobe - (F8) as well as de-stimulation of the Left Anterior Temporal Lobe (F7) enhances object recognition, and unlocks Snyder’s fabled “savant skills”.

        and/or  [8]

Anode: T1

Cathode: T3

        (?? where is T1 on the 10-20?)


Motor Drive montage [9]

This test seems to state that “bilateral tDCS over both primary sensorimotor cortices (SM1) yields more prominent effects on motor performance”.  Basicly, you can improve your motor control for things like using scissors, tying your shoes, etc.  So, this means

Anode: Right Sensory motor cortex (C4)

Cathode: Left Sensory motor cortex (C3)

Time: 20 minutes

sm_c4-c3.png


Math 5x faster

Can’t seem to find the actual montage, but bilateral dorsolateral prefrontal cortex (DLPFC) (left:F7, right:F8) is the area key to math abilities [10]

        (? where is Anode?)

        and/or [11]

Anode: P4

Cathode: P3

sm_p4-p3.png

General learning

http://tdcsplacements.com/placements/accelerated-learning/

stop mind chatter

http://www.reddit.com/r/tDCS/comments/1jjqlp/electrode_placement_for_temporarily_shutting_off/


Memory

Although TDCS show significant improvement in memory function [12] it may also slow memory response time by about 10%. [13]

Anode: F7

Cathode: Right Arm

sm_f7-ra.png


Language

searching


Observation

searching


Go-No-Go (quick decision making)[14]

Anode: F7

Cathode: Right Arm

sm_f7-ra.png


Integration/Inter-relationships

searching


Pain

7X10cm sponge with anodal stimulation on CP5, and the cathode on my right shoulder, I get very noticeable effects.[15]


Emotions

searching


Reduce depression and food cravings [16]

Anode: F3 or maybe T3

Cathode: Opposite arm

sm_f3_ra.pngsm_t3-ra.png


Boosting Attention [17]

Anode: Fp1 and Fp3

Cathode: neck

sm_f1_f3_bn.png


Improve Socialization [18]

Anode: T4, T6, P4

Cathode: L shoulder


Improve Ability (whatever that means) [19]

Anode:O1, OZ, O2

Cathode: C3 or back of neck

sm_t4-t6-p4.png


Improve Audio-Visual pitch discrimination [20]

Anode: T3

Cathode: Right shoulder

sm_t3_rs.png


Enhance motor ability and reduce pain [21]

Anode: C3 or C4

Cathode: Fp1 or Fp2

sm_c3-fp1.pngsm_c4_fp2.png


Reduce Wernicke’s Aphasia (improve comprehension) (see footnote “Article Eleven”)[22]

Anode: T5

Cathode: T6

sm_t5-t6.png


Reduce Broca’s Aphasia (improve speech) (see footnote “Article Eleven”)[23]

Anode: F5

Cathode: F6

(where are they?)   ,<= I have no recollection of what this note refers to

(see footnote “Article Eleven”) [24]


Learning Guitar (and presumably other guitar-like stuff) [25]

2mA.

SYSTEM= 10-20 electrode site

ANODE = P4 and F10. (where is F10)

CATHODE = left upper arm.

SPONGES = 13±2 cm²

START = 5 min before training

DURATION = 30 min

* in long run 1x30min is better than 2x30min but in short time 2x30min is better.


Out Of Body Experiences and/or Poker

There is no montage that specifically talk about this (that I have seen), however, the TPJ (temporoparietal junction) appears to be associated with OOBE [26].  It also seems associated with a poker players ability to bluff (and detect bluffing).  This seems to be between (and a little behind) T3 and C3 on the left and T4/C4 on the right

The Left TPJ seems to be associated with ‘perspective’ while the Right TPJ is associated with “beliefs” [27] and processing faces and bodies [28], and “for the purpose of constructing appropriate expectations and responses” [29] (this is especially useful for poker players, who need to perfect the art of lying and the art of detecting a lie)

Based on this, Possible montages might be :

upreg (anodize) right TPJ, with no downreg (Cathode on arm)  or

upreg (anodize) right TPJ and downreg (cathodize) left TPJ

 

sm_oobe.pngsm_oobe2.png

Experiments and tools

Cambridge Brain Challenge for general cognitive challenges.

Speed Math Trainer Program   ya know…for math.

Mastermind Vedic Trainer another math trainer.

Snyder’s Savant Test  to see if you’re a savant.

Spreeder for speed reading.

Memrise for learning a foreign language.

http://cognitivefun.net

http://cambridgebrainsciences.com

http://neuronation.com

http://cognifit.com

http://brainturk.com                                                                                 

http://brainworkshop.sourceforge.net/

There is an interesting test to try out your new brain-zapping tool.   Simply connect all nine of these dots with just four straight lines without lifting your finger or retracing a line.

9dots.png

In one study, 0 out of 22 (not using TDCS) found the solution.  With TDCS (using the “Insight” montage listed above) 40% of them figured it out in 10 minutes.  [30]

 

notes….

Stimulation of the DLPFC increases working memory as well as enhances mood.

Stimulation of the Right Anterior Temporal Lobe (as well as de-stimulation of the Left Anterior Temporal Lobe) enhances object recognition, and unlocks Snyder’s fabled “savant skills”.

Stimulation of Wernicke’s area improves language acquisition.

Stimulation of the Left Parietal Lobe improves math skills.

Stimulation of the Primary Motor Cortex increases motor learning and function.[31]

TDCS guided using fMRI significantly accelerates learning

http://goo.gl/lY8J9

Zap your brain into the zone: Fast track to pure focus.

http://goo.gl/azttC

Can tDCS and TMS enhance motor learning and memory formation?

http://goo.gl/GOmWA

Brain Zaps Improve Math

http://goo.gl/swvXW

Transcranial Stimulation Shows Promise in Speeding Up Learning:

http://goo.gl/TjYQh

Reddit Forum

http://www.reddit.com/r/tDCS/


[1] also designated as Broadman Areas, listed as BA1 to BA52.  See http://en.wikipedia.org/wiki/Brodmann_area

[2] http://en.wikipedia.org/wiki/10-20_system_%28EEG%29

[3] https://www.youtube.com/watch?v=0OoG-um_SBg

[4] http://www.darwinawards.com/darwin/darwin1999-50.html

[5] http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3304483/

[6] this motange is based on, but not identical to  http://www.ncbi.nlm.nih.gov/pubmed/24998841

[7] http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0016655

[8] Article Eleven - Transcranial DC Stimulation

[9] http://jn.physiology.org/content/108/12/3253

[10] http://www.cell.com/current-biology/abstract/S0960-9822%2813%2900486-7

[11] Article Eleven - Transcranial DC Stimulation

[12] http://www.ncbi.nlm.nih.gov/pubmed/16843494

[13] http://www.ncbi.nlm.nih.gov/pubmed/15819988/

[14] http://www.ncbi.nlm.nih.gov/pubmed/17166593

[15] http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3486958/

[16] Article Eleven - Transcranial DC Stimulation

[17] Article Eleven - Transcranial DC Stimulation

[18] Article Eleven - Transcranial DC Stimulation

[19] Article Eleven - Transcranial DC Stimulation

[20] Article Eleven - Transcranial DC Stimulation

[21] Article Eleven - Transcranial DC Stimulation

[22] Article Eleven - Transcranial DC Stimulation

[23] Article Eleven - Transcranial DC Stimulation

[24] Article Eleven - Transcranial DC Stimulation - as published in the International Society of Neurofeedback and Research (ISNR) Newsletter, Spring 2013. http://www.mindalive.com/1_0/article%2011.pdf

[25]from blog: http://www.getlimitless.com/Community/Blog/tabid/1263/post/Build-a-tDCS-Device/Default.aspx

[26] http://en.wikipedia.org/wiki/Temporoparietal_junction

[27] http://www.ncbi.nlm.nih.gov/pubmed/18633791

[28] www.nips.ac.jp/fmritms/conference/references/Mano/Saxe2003.pdf

[29] http://mindbrain.ucdavis.edu/people/jgeng/pdfs/GengVosselNBR_2013.pdf/at_download/file

[30] http://www.sciencedirect.com/science/article/pii/S0304394012003618

[31] http://www.longecity.org/forum/topic/63396-tdcs-electrode-placement-and-effects/