What's the word for a flashback or a rush of memories triggered by something?

I'm thinking in the context of school, like flipping through your old notebooks and just having all the knowledge flood back to you.

It's sort of like nostalgia, but more in the camp of knowledge than experiences. I've found memory boner, but that's not quite what I'm after. Is anyone familiar with a word or a description for what I've described?

Thanks in advance.

Solution 1:

Involuntary memory, as defined by Wikipedia, Involuntary Memory

The most famous literary example is from Marcel Proust, Remembrance of Things Past.

[Proust] describes an incident where he was eating tea soaked cake, and a childhood memory of eating tea soaked cake with his aunt was "revealed" to him. From this memory, he then proceeded to be reminded of the childhood home he was in, and even the town itself.

This is the incident of the madeleine.

A technical definition of involuntary memory, from the first source, above, is:

Involuntary memory, also known as involuntary explicit memory, involuntary conscious memory, involuntary aware memory, and most commonly, involuntary autobiographical memory, is a subcomponent of memory that occurs when cues encountered in everyday life evoke recollections of the past without conscious effort. Voluntary memory, its binary opposite, is characterized by a deliberate effort to recall the past

Solution 2:

a flood of memories

I know you use 'flood' in the question as a verb, but perhaps use it as a noun. Quoting macmillandictionary.com

4 [countable] a flood of memories or feelings is a lot of strong memories or feelings that suddenly affect you

> The song brought back a flood of memories.

Solution 3:

Take a trip down memory lane: To reminisce over memories of past events, especially happy ones.

My grandmother spends more time taking trips down memory lane these days than talking about the present.

_{EDIT: Oops! I've just read the "more in the camp of knowledge than experiences" part. However, I think it's a nice idiom—so it's worth considering it!}

Not 100% an idiom, but also consider: