Will There Ever Be a Drug with No or Negligible Side Effects? Evidence from Neuroscience

Arguments in the neuroenhancement debate are sometimes based upon idealistic scenarios involving the assumption of using a drug that has no or negligible side effects. At least it is often implicitly assumed – as technology and scientific knowledge advances - that there soon will be a drug with no or negligible side effects. We will review evidence from neuroscience, complex network research and evolution theory and demonstrate that - at least in terms of psychopharmacological intervention – on the basis of our understanding of brain function it seems inconceivable that there ever will be a drug that has the desired effect without undesirable side effects. We will illustrate this by reference to enhancing edge detection in V2 in monkeys and demonstrate that even for this localised single neuron coded function there would be numerous side effects. Taking the more realistic case of pharmacological enhancement that is inevitably associated with side effects will change consequentialist arguments for neuroenhancement and have implications for the conception of autonomy, specifically in the case of performance enhancement. We conclude that a neuroethics debate that aims to inform policy decisions should take these findings into account. We hope that our article will precipitate more interdisciplinary research in neuroscience and philosophy.