Pupil Dilation Reflects Objective Explicit Memory While Reaction Time Reflects Implicit Memory in Visual Old/New Recognition

We sought out to replicate objective and subjective pupillary old/new effects in a traditional non-verbal object recognition paradigm. Our results showed a replication of the objective effects, however, not the subjective. Surprisingly, we found an implicit memory effect that suggests partial retrieval of oldness below the threshold of conscious awareness.