Table 2: A preliminary classification of déjà vu, déjà vécu, and involuntary memories.

Déjà vuDéjà vécuInvoluntary memories

Feelings
 Familiarity
 Prescience
 Mental time travel
 Characterisation“Prior occurrence”“Prior experience”“Prior episode”
Content
 Emotion
 Visual images
 Source or context
 Narrative-like coherence
 A defined past
 RecallNonePartialComplete
Time courseShorterLonger

Note: we would see that all these experiences should share these same characteristics; they would all be experienced involuntarily and they will all be relatively brief mental phenomena.