An apparatus for treating neurological disorders comprising at least one electrode implantable in a patient's brain and a processing and stimulation device connected to the at least one electrode. The processing and stimulation device comprises at least one stimulation module adapted to generate a stimulation signal characterised by a plurality of parameters； at least one acquisition module adapted to acquire a signal characteristic of cerebral activity and determine its power in at least one frequency band； and at least one control module of at least one parameter of the stimulation signal as a function of the power of the signal characteristic of cerebral activity acquired, based on a transfer function having a saturating trend, wherein the transfer function is configured to set the at least one parameter of the stimulation signal differently dependent on a plurality of power ranges, by keeping the parameter within a predetermined stimulation range.
