ADHD often (not always, there's a few types) comes with an inability or reduces ability to direct ones focus. It is believed that the mechanism behind this is one of early or overzealous dopamine reuptake.

Mammalian brains have a reward system based on the release and reuptake of dopamine. Perform survival task, get some dopamine. People with ADHD, due to their overzealous reuptake, do not build up significant enough amounts of dopamine for this reward system to function as normal. As a result of this, when someone with ADHD is cleaning (a task that would normally supply enough dopamine to hold attention) and sees the box of nostalgia, enough dopamine is released by interacting with the nostalgia box (because nostalgia) to override the attention on the task and shift it to the fun engaging box of stuff.