Atypical absence seizures are distinct from typical absence seizures and generally result in changes in postural tone. The appearance of other symptoms is variable and differs between the various absence epilepsy syndromes. 3 Outside factors that may trigger seizure activity include emotions, time of day, metabolic factors (including hyperventilation), and periods of changing attentiveness. 2,3 Other manifestations may include brief unconscious behaviors (automatisms), autonomic disturbances (i.e., maintenance of heart rate, pupil function, or sweating), and brief involuntary muscle twitching (myoclonia). Symptoms generally are brief (usually 20 seconds) have a sudden onset that interrupts ongoing activities and may occur up to 200 times per day, almost every day. Typical absence seizures involve a transient loss of consciousness that is similar to that seen in other seizure types, but without prominent convulsive episodes.
1 Typically thought of as a type of childhood seizure disorder, absence seizures also may present in older populations or as a component of multiple other epileptic disorders. First described in the early 1700s, absence seizures have been referred to over the years as petits accès, petit mal, epilepsia minor, and pyknolepsy.
