In the 1950's, Emily had a procedure done to her in which the doctor used an instrument to cut the nerve fibers connecting her prefrontal cortex to the rest of the brain. This procedure, called _____________, left her withdrawn and unable to care for herself.

A) ECT
B) deep brain surgery
C) a lobotomy
D) transcranial stimulation

The procedure described in which nerve fibers connecting the prefrontal cortex to the rest of the brain are severed is a lobotomy. Option A, ECT, refers to electroconvulsive therapy, which involves passing electric current through the brain to induce seizures and is used for treating certain mental illnesses. Option B, deep brain surgery, involves implanting electrodes into specific areas of the brain and is used to manage movement disorders like Parkinson's disease. Option D, transcranial stimulation, involves using a non-invasive procedure to send magnetic signals to the brain and is used to treat depression and migraines.