science

I have friends from elementary school who I routinely will try to find and ask them about stuff from third grade.

The vast majority of them have no idea who I am -- I ran this experiment a few more times with people from middle school and high school, and then college.

I have determined that the average long-term memory for human being is 7 years.

After 7 years you basically get deleted from their memory and while you can prompt their long-term memory it's a bit almost like memory implantation you're giving them information about something which may or may not be true.

E.g: "Remember that hot air balloon ride we went on when we were six?"

"Haha, yeah I remember."

"Really? Because that's some bullshit I just made up there's no hot air balloons in the city."