Slang for ECT or Electro-Convulsive Therapy, a modern of version of the mental health procedure that hopefully shocks a patient out of their madness. It was graphically depicted in the movie "One Flew Over the Cuckoo's Nest" starring Jack Nicholson. The modern procedure involves sedatives and anti-convulsive drugs to prevent injury to the patient and typically the procedure lasts less than 2 minutes. Used as a last resort treatment, common side effects include memory loss.
My friend went to get Shock Treatment and now she forgets what we did together.