The frontal lobe is the most anterior of the lobes. The boundaries of the lobe are the central sulcus (which seperates it from the parietal lobe) and the lateral fissure (which seperates it from the temporal lobe). The frontal lobe mediates a wide variety of functions. Reasoning, judgement,emotional response, planning and execution, and control of voluntary muscles; the frontal lobe is also involved in production of speech and contains the motor speech area (Brocas area).