What type of treatment involves the removal or alteration of parts of a person's personality?

The treatment that involves the removal or alteration of parts of a person's personality is lobotomy. This historical psychiatric procedure was designed to treat severe mental disorders by surgically severing connections in the brain's prefrontal cortex. It was believed that this would help alleviate symptoms of conditions such as schizophrenia or severe depression by altering the way emotions and thoughts were processed. Lobotomies were used in the mid-20th century, but they became controversial due to their irreversible nature and the significant changes they could cause in a person’s personality and behavior.

In contrast, psychoanalysis focuses on exploring the unconscious mind and childhood experiences to help individuals understand their thoughts and feelings. Cognitive-behavioral therapy emphasizes changing negative thought patterns to influence behavior positively rather than altering brain structure. Exposure therapy is a behavioral treatment used to help individuals confront fears in a controlled environment, again without any physical alteration to personality or brain function. Each of these alternatives aims to address psychological issues through non-invasive methods that do not involve altering brain anatomy.