Final answer:
The case of Phineas Gage, who suffered frontal lobe damage due to a railroad construction accident, demonstrates that such an injury can alter one's personality, indicating the significant role the frontal lobe plays in personality and behavior. Option d) is correct.
Step-by-step explanation:
The classic case of railroad worker Phineas Gage best illustrated that frontal lobe damage can alter one's personality. On September 13, 1848, Gage suffered a traumatic accident while working on a railroad where an iron rod passed through his frontal lobe. This led to significant changes in his behavior and personality, as described by those who knew him before and after the accident.
The frontal lobe, and in particular the prefrontal cortex, plays a crucial role in personality, planning, judgment, reasoning, and working memory. Damage to this area, as in the case of Phineas Gage, can result in major alterations in personality, mood, and behavior. Gage's friends and acquaintances noted that he became irritable, impulsive, and behaved inappropriately, all of which indicates a loss of impulse control—a function attributed to the frontal lobe.