  Acquisition of fine motor skills is a time-consuming process as it requires
frequent repetitions. Transcranial electrical stimulation is a promising means
of enhancing simple motor skill development via neuromodulatory mechanisms.
Here, we report that non-invasive neurostimulation facilitates the learning of
complex fine bimanual motor skills associated with a surgical task. During the
training of 17 medical students on the Fundamentals of Laparoscopic Surgery
(FLS) pattern cutting task over a period of 12 days, we observed that
transcranial direct current stimulation (tDCS) decreased the error level and
the variability in performance, compared to the Sham group. By concurrently
monitoring the cortical activations of the subjects via functional
near-infrared spectroscopy (fNIRS), our study showed that the cortical
activation significantly stimulated by tDCS. The lowered performance error and
the increased brain activation were retained after one-month post-training.
This work supports the use of tDCS to enhance performance accuracy in fine
bimanual motor tasks.
