Starting from the 20s, researchers have begun to explore the possibility to create ‘hybrid’ systems in vitro at the interface between neuroscience and robotics (I will call them ‘neurohybrid interfaces’), thus providing an excellent test bed for modulation of neuronal tissue and forming the basis of future adaptive, bi-directional Brain Machine Interfaces and neuroprostheses. The first-ever in vitro closed-loop neurohybrid system consisted of a lamprey brainstem bi-directionally connected to a small wheeled robot. Inspired by that and other pioneering studies, a bi-directional system involving in vitro neocortical networks grown on Micro Electrode Arrays (MEAs) and a small robot was developed and tested in my lab. A similar technology could be exploited also for brain repair, with relevance in the field of cognitive neuroprosthetics. The idea is to use closed-loop neurohybrid interfaces to treat the neuronal injury in the brain, where the damage is actually located, and to possibly promote brain plasticity in order to speed up the recovery process. Within this framework, I will show two examples. I will start by presenting the development and the results related to an in vitro ‘brain-prosthesis’, aimed at restoring the communications between damaged neuronal networks. Then, I will present recent results related to closed-loop paradigms for brain repair in vivo, focusing on how different types of stimulation can affect the neural activity. Further developments and applications in the fields of neurorehabilitation and neurorobotics will be briefly introduced and discussed.