recognition memory Page 197

Recognition memory is the brain’s party trick for spotting something you’ve seen before without needing a full biography of it.

It runs on two engines: quick-and-dirty familiarity (that “I know that face” feeling) and detail-rich recollection (where, when, and why you met it).

Psychologists test it with old/new or forced-choice tasks, crunching the results with measures like d′ to separate genuine memory from optimistic guessing.

It’s boosted by spacing and deeper processing, and leans on the medial temporal lobe—perirhinal cortex for familiarity, hippocampus for recollection.

When it misfires, you get déjà vu, false alarms, and the odd awkward hello to a total stranger.