Why non-invasive brain stimulation should not be used in military and security services

Abstract

In a recent review article by Levasseur-Moreau et al. (2013), the authors discussed the effects of non-invasive brain stimulation (NIBS) on cognitive functions and proposed a potential application of NIBS in security or military personnel. We believe that this research endeavor is questionable since it might disclose several scientific as well as ethical concerns. In the following, we highlight our reservations about the potential use of NIBS in army and/or security services. Over the past decades, non-invasive brain stimulation (NIBS) techniques such as transcranial magnetic (TMS) or transcranial direct current stimulation (tDCS) have been extensively used to investigate brain function and brain plasticity in the living human brain. Early studies provided evidence that NIBS is capable of evoking short-lasting modulatory effects on brain functions. Based on this finding, subsequent proof-of-principle studies quickly progressed to also affect motor and cognitive functions. Originally, NIBS techniques were primarily used in basic research to unravel physiological brain processes and/or to establish brain-behavior relationships. The underlying motivation for many researchers is to extend the boundaries of knowledge and to translate findings of basic research into clinical science, that is, to develop new adjuvant therapeutic tools. In fact, NIBS might be a promising tool for the treatment of neurological and psychiatric diseases (Floel, 2013). For example, Hummel and colleagues showed a beneficial effect of a short period of tDCS in chronic stroke patients on paretic hand function (Hummel et al., 2005). Based on this finding, the authors and other subsequent studies (Lindenberg et al., 2010) suggested that such interventional strategies in combination with customary rehabilitative treatments may play an adjuvant role in neurorehabilitation. Nevertheless, clinical trials on larger patient samples are still needed to confirm the promising results that have been achieved so far by smaller clinical studies. Apart from a translation to the clinical settings, it has been suggested to use these techniques for “neuroenhancement” in cognitive abilities or sports, fueling a vivid discussion concerning ethical issues of the use of NIBS in healthy human subjects (Hamilton et al., 2011; Brukamp and Gross, 2012; Cohen Kadosh et al., 2012; Banissy and Muggleton, 2013). However, to our mind, the use of these techniques in military or security personnel goes even a step further and accentuates concerns as compared to the use in “civilians.” First, the use of NIBS in military or security services is problematic with respect to the autonomy of individuals receiving NIBS: In the military context, the risk of coercion is much more pronounced and autonomous decisions cannot always be warranted (Tennison and Moreno, 2012). Second, safety issues might be aggravated in this context and might not only apply to the person receiving NIBS but also to third persons. Both safety and autonomy represent principles that may help to identify ethical problems and guide related decisions (Beauchamp and Childress, 1994; Walker, 2009; Brukamp and Gross, 2012).