<P> Focal impaired awareness seizures are often preceded by an aura . The seizure aura is a focal aware seizure . The aura may manifest itself as a feeling of déjà vu, jamais vu, fear, euphoria or depersonalization . The aura might also occur as a visual disturbance, such as tunnel vision or a change in the perceived size of objects . Once consciousness is impaired, the person may display automatisms such as lip smacking, chewing or swallowing . There may also be loss of memory (amnesia) surrounding the seizural event . The person may still be able to perform routine tasks such as walking, although such movements are not purposeful or planned . Witnesses may not recognize that anything is wrong . </P> <P> Focal impaired awareness seizures might arise from any lobe of the brain . They most commonly arise from the mesial temporal lobe, particularly the amygdala, hippocampus, and neocortical regions . A common associated brain abnormality is mesial temporal sclerosis . Mesial temporal sclerosis is a specific pattern of hippocampal neuronal loss accompanied by hippocampal gliosis and atrophy . Focal onset impaired awareness seizures occur when excessive and synchronous electrical brain activity causes the impaired awareness and responsiveness . The abnormal electrical activity might spread to the rest of the brain and cause a focal to bilateral seizure or a generalized tonic--clonic seizure . The newer classification of 2017 groups only focal and generalized seizures, and generalised seizures are those that involve both sides of the brain from the onset . </P> <P> Jacksonian seizures are named after their discoverer, John Hughlings Jackson, an English neurologist, whose studies led to the discovery of the seizures' initiation point (in the primary motor cortex) in 1863 . </P>

Where do partial seizures originate in the brain