The case of Phineas Gage enabled psychologists to study the effects of personality and behavior in relation to damage associated with his frontal lobe. Gage was injured when a rod pierced his skull and destroyed most of his left frontal lobe. Researchers studied Gage and noted changes in his behavior the occurred directly after and as a result of the incident. As a result, they concluded that the frontal lobe plays a key role in a person's behavior. This case is best categorized by which of the following methods of psychological research?

The case of Phineas Gage enabled psychologists to study the effects of personality and behavior in relation to damage associated with his frontal lobe. Gage was injured when a rod pierced his skull and destroyed most of his left frontal lobe. Researchers studied Gage and noted changes in his behavior the occurred directly after and as a result of the incident. As a result, they concluded that the frontal lobe plays a key role in a person's behavior. This case is best categorized by which of the following methods of psychological research?