Abstract:

Familiarity and recollection are two independent cognitive processes involved in recognition memory. It is traditionally believed that both familiarity and recollection can support item recognition, whereas only recollection can support associative recognition. However, the unitization hypothesis argues that familiarity can also make a contribution to associative memory when the to-be-remembered stimuli are unitized as a single unit. Here we review results from behavioral, electrophysiological and functional neuroimaging studies which all convergently show that unitization indeed induces the contribution of familiarity to the associative retrieval, and perirhinal cortex is involved in the unitized encoding processes and subsequent familiarity-based associative retrieval. Future studies need to overcome the methodological problems, to explore the brain functional network associated with unitized processes, and to use the unitized encoding strategies to improve episodic memory in selective populations.

Key words: unitization, familiarity, recollection, associative recognition, source memory, perirhinal cortex