A lot of the ‘pop sci’ articles are drawing on the results of only a few studies. Hopefully we’ll get affirmation of the efficacy of tDCS in cognitive enhancement soon.
Does Passing A Small Current Through Your Brain Really Make You Smarter?
Excellent update from Giulio Ruffini of Neuroelectrics. Full of links to relevant papers.
tDCS and Stroke: What We Know So Far (Jan 2013)
As far as I can tell, this is a new development in understanding the mechanism for the mediation of pain using tDCS.
Immediate effects of tDCS on the μ-opioid system of a chronic pain patient
To our knowledge, we provide data for the first time in vivo that there is possibly an instant increase of endogenous μ-opioid release during acute motor cortex neuromodulation with tDCS.
(And the pop-sci media follow-up Electrical Current Can Unlock The Seriously Good Drugs In Your Brain and Happiness Is a Warm Transcranial Direct Current Electrode)
A lot of research is going on right now into understanding where exactly, current if flowing.
The electric field in the cortex during transcranial current stimulation
The aim of this study was to investigate the effect of tissue heterogeneity and of the complex cortical geometry on the electric field distribution.
Some context.
A pioneer work on electric brain stimulation in psychotic patients. Rudolph Gottfried Arndt and his 1870s studies.
Today’s brain stimulation methods are commonly traced back historically to surgical brain operations. With this one-sided historical approach it is easy to overlook the fact that non-surgical electrical brain-stimulating applications preceded present-day therapies.
Mental Practice, or MP is practicing doing something without actually doing it. A musician imagining playing their instrument for instance. This study measured quality of handwriting with the non-dominant hand while using tDCS.
Site-specific effects of mental practice combined with transcranial direct current stimulation on motor learning
In conclusion, our results suggest that MP-induced effects in improving motor performance can be successfully consolidated by excitatory non-invasive brain stimulation on the M1 and left DLPFC.