A device and method for desynchronizing a patient's neuronal brain activity in which the neuron population is firing in a pathologically synchronized manner. The device includes a stimulation unit that generates an acoustic stimulation signal that includes both a first tone and a second tone. The first tone is provided to shift the phase of the neuronal brain activity of a first subpopulation of the neuron population relative to the phase of the neuronal brain activity of a second subpopulation of the neuron population when the first tone is acoustically received by the patient. Further, the second tone is provided to shift the phase of the neuronal brain activity of the second subpopulation relative to the phase of the neuronal brain activity of the first subpopulation when the second tone is acoustically received by the patient. As a result, the acoustic stimulation signal desynchronizes the stimulated neuron population.