In a study published in December Frontiers in Systems Neuroscience, Nick Davis and Martijn van Koningsbruggen suggest that using the term “non-invasive” to describe interventions like tDCS is “inappropriate and perhaps oxymoronic,” as it obscures the possible side-effects and long-term effects that brain stimulation might lead to.
“We argue that the traditional definition of an invasive procedure, one which requires an incision or insertion in the body, should be re-examined.”
Davis and Van Koningsbruggen suggest that the term “non-invasive brain stimulation” might lead some non-expert users of electrical brain stimulation to believe “that the effect of the technique is necessarily mild.”
Gamma-knife radiotherapy, they write, “is also ‘non-invasive’ in the sense that no incisions or insertions are made in the person…”
They also remind researchers to “be mindful that in a climate of wide and open dissemination of scientific results, exciting, and beneficial results will reach well beyond the labs and clinics,” for example here and here.