Frontal lobe signs usually involve the motor system, and may include many special types of deficit, depending on which part of the frontal lobe is affected:

unsteady gait (unsteadiness in walking)

muscular rigidity, resistance to passive movements of the limbs (hypertonia)

paralysis of a limb (monoparesis) or a larger area on one side of the body (hemiparesis)

paralysis head and eye movements

inability to express oneself linguistically, described as an expressive aphasia (Broca's aphasia)

focal seizures which can spread to adjacent areas (Jacksonian seizure)

grand mal or tonic-clonic seizures

changes in personality such as disinhibition, inappropriate jocularity, rage without provocation; or loss of initiative and concern, apathy, akinetic mutism, general retardation

“frontal release” signs, i.e. reappearance of primitive reflexes such as the snout reflex, the grasp reflex, and the palmar-mental reflex

unilateral loss of smell (anosmia)