Lobotomy
A lobotomy was a neurosurgical procedure which consisted of cutting away most of the connections to and from the prefrontal cortex.

Among Vulcans, repressed memories caused a physical reaction within the brain which in extreme cases could lead to the mind of the patient literally lobotomizing itself. ()

In 2374, Tom Paris compared the Mari's Engramatic purge, a procedure to remove violent thoughts from someone's brain, a lobotomy. ()

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Medical procedures