Brain navigation methods and device

A method for automatically navigating an electrical lead having at least two electrodes to a selected brain target, comprising:

• a. training a brain navigation system;
• b. automatically continually advancing said electrical lead comprising at least two electrodes through brain tissue along a selected insertion trajectory;
• c. automatically recording differential electrical signals by said at least two electrodes during said automatically continually advancing;
• d. automatically analyzing said recorded differential electrical signals using stored reference indications of electrical signals associated with tissue along said insertion trajectory;
• e. automatically estimating proximity between a distal end of said electrical lead to said selected brain target based on results of said analyzing;
• and
• f. automatically modifying sampling and/or recording rate of said recording electrical signals based on said estimated proximity to said selected brain target;
• wherein said modifying comprises increasing sampling rate and/or recording rate when the electrical lead is in proximity to the said selected brain target.