Amnesia, known as Dumb in the Neo Demiforce fan-translation of the Famicom version, is a stronger form of Silence, preventing the use of spells and lasting until it is cured, either by a Mallet or Esuna at Lv.3 or higher.
Amnesia (アムネジア, Amunejia?, lit. Amnesia) is a status effect in Final Fantasy XI which prohibits a player from using any job abilities or weapon skills. Players can still cast spells and attack as normal. Imps are the most common imposers of the status effect with their common ability Abrasive Tantara, though Lamiae, Qiqirn, and Ladybugs also have the ability to inflict the status.
Players who are afflicted with Amnesia may experience some difficulty in removing it, although the enchantment of the Ecphoria Ring can remove the effect when inflicted by certain of the weaker monsters. An ounce of prevention is worth a pound of cure in this case.
Some protection against Amnesia may be obtained through the white magics Baramnesia or Baramnesra, Barfire or Barfira (as Amnesia is a Fire-aligned status), and the job trait Resist Amnesia. The Negate Amnesia (ネゲートアムネジア, Negēto Amunejia?, lit. Negate Amnesia) status bestowing temporary item Amnesia Screen (抗アムネジア薬, Kouamnejiayaku?, lit. Anti-Amnesia Medicine) available in Abyssea will prevent Amnesia completely for two minutes.
Impairment (インペア, Inpea?, lit. Impair) is a very similar status that is inflicted as part of the Pathos of Alzadaal on those who dare venture deep into the Ruins of Alzadaal to take part in Salvage. It is removed by leaving the ruins, or by obtaining and using a Opacus Cell (in this case, not even dying will help).