Answer:
This is known as "Imagination inflation"
Step-by-step explanation:
Imagination inflation is a type of memory distortion. Imagining an event that never happened increases the person's confidence that such event actually occurred. Imagining a false event makes people feel that such event is more familiar, and people mistake this feeling for the fact that they have experienced the event. Nonetheless, imagination inflation may be the result of source confusion. When people imagine a false past event, they generate information about it, they store it in their memory. Later, they might remember the contents of said event but not its source.
The more frequent the imagining of an event, the stronger the confidence that it actually happened.