Thanks for reading so far, especially if you are not a friend or family.

All this work have been possible thanks to the wonderful BRAIN STIMULATION Translational Lab translationalbrainstim.com and our collaborators 13/13

Hopefully, these results can improve tDCS effects and its efficacy for the treatment of different conditions, specially since the human brain is also highly convoluted and neurons have widely different orientations 12/13

Finally, we used Neuropixel recordings to corroborate these results in simultaneously recorded neurons which have opposite orientations in the cerebellum, also corroborating the effect in behaving condition 11/13

While neurons pointing away from the electrode decrease⬇️their activity for anodal stimulation and increase⬆️for cathodal (lower half). This phenomenon could be explained by the polarization of the neuron and changes in membrane resting potential (more in the paper) 10/13

Matching the orientation of the neurons with their modulation under tDCS, we discovered that their orientation was a key factor determining tDCS effects, with neurons pointing toward the electrode increasing⬆️their activity for anodal stimulation and decreasing⬇️for cathodal (upper half) 9/13

To solve this puzzle, we performed juxtacellular labelling of the recorded neurons in anesthetized mice, obtaining these awesome images: 8/13

We observed this heterogeneous modulation in all types of neurons in the cerebellum, among them the Purkinje cells, which are particularly interesting since they are the only output from the cerebellar cortex 7/13

But, at the same time other neurons were modulated in just the opposite way, with anodal decreasing⬇️but cathodal increasing⬆️their activity 6/13

To address this, we applied tDCS and record the activity of individual neurons in behaving mice🐭. As expected, we observed neurons increasing⬆️their activity under➕electrical currents (anodal tDCS, red) and decreasing during➖currents (cathodal tDCS, blue) 5/13