Synonyms to decay of memory

absentmindedness, Lethe, Walter Mitty, absence of mind, absorption, abstractedness, abstraction, bemusement, brown study, carelessness, castle-building, daydream, daydreamer, daydreaming, depth of thought, disregard, disregardfulness, distraction, dream, dreaming, engrossment, fantasy, fantasying, fit of abstraction, flightiness, flippancy, forgetfulness, forgetting, forgiveness, frivolousness, giddiness, hazy recollection, heedlessness, inadvertence, inadvertency, inattention, inattentiveness, inconsideration, incuriosity, indifference, inobservance, levity, lightmindedness, mooning, moonraking, muse, musefulness, musing, muted ecstasy, negligence, nepenthe, nirvana, nonobservance, obliteration, oblivion, obliviousness, pipe dream, pipe-dreaming, preoccupation, regardlessness, reverie, shallowness, short memory, stargazing, study, superficiality, thoughtlessness, trance, unalertness, unawareness, unconsciousness, unheedfulness, unintentiveness, unmindfulness, unobservance, unwariness, unwatchfulness, waters of oblivion, woolgathering