Possession of the land must continue for the state's predetermined statutory period. The statutory period for adverse possession may be as short as three years or as long as twenty years. Many jurisdictions allow an adverse possessor to "tack on" his or her period of adverse possession to a previous possessor's period, so long as there is no lapse in time between the two occupations. A statutory period will not begin running if a landowner is an infant (below the age of majority), if the landowner is deemed insane, or if the landowner is incarcerated. If the landowner suffers from one of the above conditions during the statutory period, the statutory period will not be tolled and may continue uninterrupted.