Modern developments in basic and in clinical neuroscience have currently triggered an intense debate about the ethical questions related to these developments. A specific characteristic of brain interventions in the widest sense is the fact that we intervene with the natural ground of the epistemic instance itself, the instance which enables us to autonomously gain the insights that are necessary to adequately monitor and evaluate any sort of intervention related to our own body. In the case of brain pathology or therapeutic brain intervention the continuous capacity of gaining insights can be disturbed or even disrupted. This preculiarity by itself constitutes a neuroethical discourse, next to the technical developments in brainreading. We aim at a differentiated way of neuroethical reasoning, which builds upon objective criteria. Here, I will use principilism as an ethical background and suggest a criteriology for a differentiated neuroethics, which takes into account aspects of the aim, the model, the means, and the purpose of brain interventions. All these aspects appear to be relevant for a proper and adequate evaluation of whether brain interventions can be justified or not.