One of the five mental disturbances - vikalpa.

Playing with fanciful thoughts or words and living in one’s own world of thoughts and impressions which have no substantial basis is vikalpa (in Sanskrit) - a vague and uncertain knowledge which does not correspond to reality.

Listening to your thoughts when you get up in the morning after a sleep can really define that the “story within” is without substance. (Ref Patanjali 1,9 Iyengar translation)

Om Shanti