The dorsolateral prefrontal cortex is associated with working memory and actively holds many pieces of transitory information. There is still discussion going on whether or not the DLPFC is a specialized type of working memory such as computation mechanisms, or if it contains certain content namely visuospatial information (which allows us to mentally picture coordinates within the spatial domain).
To boost memorization & learning an anode is placed on FP1 or FP2, with a contralateral shoulder cathode. A large anode electrode could also be placed across FP1 and FP2 at 2 mA, with a neck-placed cathode.
This studies findings concluded that stimulation over the DLPFC had lead to an enhancement of verbal memorization while cathodal stimulation had impaired the memorization rate.
Siever, D. (2013). Transcranial DC Stimulation. Neuroconnections, Spring Issue, 33-40. http://www.mindalive.com/1_0/article%2011.pdf.
I have to point out. The DLPFC is not located at FP1, it is located at F3 on the 10/20 system. The study you mention above specifically points out the DLPFC and not FP1. In fact, there is no study anywhere that suggests anodal stimulation of FP1 will increase memory or learning. Please correct the electrode placement.
You are correct, thanks for the information. I went ahead and updated the placement.