a brief temporary alteration in movement, sensation or autonomic nerve function caused by abnormal electrical activity in a localised area of the brain. Focal seizures (i.e. Partial or jacksonian seizures) usually cause no change in awareness or alertness. An example of a focal (partial) seizure would be rhythmic muscle contractions in one area of the body: lip smacking, mouth movements, drooling, head turning, eye movements or seemingly purposeful movements (for example picking at clothes). Other presentations may be strictly sensory with abnormal numbness, tingling or a crawling sensation to the skin. More unusual symptoms include changes in speech, thought, personality, mood, sensation of deja vu or hallucinations.