Familiarity as a Separate Memory System

What it is

Memory research distinguishes knowing that something has been met before from recalling the episode itself. Charan Ranganath describes the two as separate signals in Why We Remember. Cleary and Claxton found that resemblance to a scene people had seen but did not recall raised reports of déjà vu, which fits a familiarity signal arriving without recollection.

In effect

In the article on déjà vu, it explains how a moment can feel known when its source cannot be found.

What it does not say

It describes two kinds of memory signal. It does not say that they never work together.

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