THE ESSENTIAL
- Deja vu is the feeling of having already witnessed or experienced a present situation.
- It is often accompanied by a feeling of unreality or strangeness.
“The feeling of deja vu generally lasts no more than thirty seconds. It occurs more indoors than outdoors and at the end of the day”, comments the B2V Observatory of Memories.
Fatigue and stress are predisposing factors
Deja vu affects more or less everyone but it is more present in the youngest and tends to disappear with age. Fatigue and stress are predisposing factors, “because perhaps they modify the resources of attention”, continue the experts. These experiences usually recur several times in the same subject.
Interpretations or attempts to explain the phenomenon of “déjà vu” are multiple, even if the most common concerns “a kind of dissociation of the two physiological processes of our memory generally activated together: familiarity and recall”explain the specialists.
Deja-vu might also occur in an experience or an aspect (an object, a place, a face etc.) already familiar but whose recognition is prevented by a different context, which leads to identify “excessively” the whole scene as familiar. The control being put in place, quickly the person understands that it is “a subjective feeling” and not a reality.
When should we be worried?
Whatever the explanation, “the phenomenon is in some way physiological (a bit like sometimes the feeling of the word at the tip of the tongue or the lapsus) and should not worry unless it is repeated often, if it is very monothematic or occurs for a prolonged period “, reassures the B2V Observatory of Memories.
Deja vu nevertheless exists in a certain number of pathological situations and is therefore no longer normal. In neurology, we can cite temporal epilepsy, but the sensation is then often sensed and identical from one experience to another. It is also reported in psychiatric illnesses and during the consumption of psychostimulant products (amphetamines).