Broca's aphasia is caused by damage to Broca's area, a region in the left frontal lobe of the brain that controls speech production. The most common cause is stroke, but it can also result from traumatic brain injury, brain tumors, or infections. When this area is damaged, the brain's ability to plan and execute the motor movements needed for speech is disrupted. The severity depends on the size and exact location of the damage โ some people have mild word-finding difficulties, while others struggle to produce more than a few words at a time.