A device for stimulating neurons that includes a stimulation unit implantable in the body of a patient and having stimulation elements that stimulate neurons in the brain and/or spinal cord. A control unit controls the stimulation unit during first and second time intervals in different stimulation modes. The control unit controls the stimulation unit during 75% or more of the first time interval in the first stimulation mode to repeatedly generate sequences of stimuli and the order in which the stimulation elements generate stimuli is constant for not more than 5 successively generated sequences and then varied. The control unit controls the stimulation unit during 75% or more of the second time interval in a second stimulation mode such that the stimulation elements repeatedly generate sequences of stimuli and the order in which the stimulation elements generate stimuli is constant for at least 25 successively generated sequences and then varied.