Self-organization and plasticity are fundamental mechanisms of the brain. Learning processes are enabled by activity-dependent changes of the synaptic connectivity within neuronal networks (synaptic plasticity of the brain).
Hereby neuronal populations can be arranged in qualitatively entirely different states: In a healthy state a neuronal population can be weakly synchronized with weak synaptic connectivity; in pathological conditions, however, the neuronal population has pathologically strong synaptic connections and is, hence, strongly synchronized; i.e. the neurons of the population are particularly coupled to each other and firing in synchrony. With Coordinated Reset (CR®) stimulation neuronal populations can be shifted from a diseased to a healthy state. For this purpose, mild (the phase of the pathological oscillation) resetting stimuli are applied at different stimulation sites at different times. A coordinated reset is a sequence of mild stimuli, which alter the firing of the stimulated nerve cells only minimally and in particular, neither suppress the nerve cell activity nor cause significant changes in the discharge rate of neurons. Rather, the CR® stimuli just act on the particular stimulated subpopulation in a way that the subpopulations get out of phase with respect to each other. Caused by the pathological interaction of the neuronal population, automatically a complete desynchronization follows. For the development of CR®-stimulation the affected populations were simulated in mathematical models. Related methods of statistical physics, biophysics and nonlinear mathematics have been used to deploy fundamental self-organization processes and plasticity rules of the nervous system. The desynchronization significantly changes the synaptic connectivity of the affected neuronal populations. The therapeutic effect therefore outlasts the stimulation. Due to the underlying biophysics CR®-stimulation can be realized through different stimulation approaches. CR®-stimulation can be applied invasively, e.g. via implanted brain electrodes as electrical brain stimulation. CR® can also be realized non-invasively, via sensory stimuli, e.g. acoustic stimuli.