Some posible problems:

what type of device did you used ?

current?

current density of electrodes?

refference electrode position?

use EEG or TENS electrodes is bad idea they have wrong current density and resistence and dnagerous electrochemial products

use saline soaked electrodes of right current density

http://brmlab.cz/project/brain_hacking/tdcs http://www.longecity.org/forum/topic/50076-tdcs-thread/page__st__30__gopid__503859#entry503859

shutting down internal monologue lower muscle tension by deactivation the negative part of limbic system