Electrical stimulation system and method for stimulating nerve tissue in the brain using a stimulation lead having a tip electrode, having at least five electrodes, or both

An electrical stimulation system for electrically stimulating target nerve tissue in a person's brain using a stimulation lead having at least five electrodes, comprising:

• a stimulation lead adapted for implantation into the brain for electrical stimulation of target nerve tissue in the brain, the stimulation lead comprising at least five electrodes, the stimulation lead adapted to be implanted in the brain such that one or more of the at least five electrodes are positioned proximate the target nerve tissue in the brain to deliver electrical stimulation pulses to the target nerve tissue in the brain, the at least five electrodes comprising:
• a tip electrode located at a distal tip of the stimulation lead, having a substantially spherical distal surface, and adapted to emit a substantially monopolar field in delivering electrical stimulation pulses to the target nerve tissue in the brain;
• and
• at least four circumferential electrodes spaced apart from the tip electrode and from one another along the stimulation lead;
• the tip electrode adapted to be controlled independently from the at least four circumferential electrodes;
• and
• a stimulation source operable to generate the electrical stimulation pulses for transmission to the one or more of the at least five electrodes of the stimulation lead positioned proximate the target nerve tissue in the brain to cause the one or more of the at least five electrodes to deliver the electrical stimulation pulses to the target nerve tissue in the brain.