Language abilities are controlled primarily by various parts of the brain's left hemisphere - especially in right-handers. Those parts of the frontal lobe responsible for movement also control speech. This explains why patients who have problems speaking also usually have limb paralysis/weakness, as the motor part of the brain that controls these movements is near to the part that controls speech movements. Aphasia is the general term for language impairment. Given that different parts of the left hemisphere control different aspects of language, the type of problem that occurs depends on which area/s is injured. This is why there are various combinations of problems. Broca's aphasia results from damage to the front half of the left side of the brain - in the frontal regions next to the part of the brain that controls movement of the face. Patients with global aphasia cannot speak.