Semantic mediation of age-related deficits in episodic recognition of common odors.

In the present research, the relationship between various semantic memory functions and episodic odor memory across the adult life span is addressed. In contrast to earlier evidence that odors may be encoded and stored as unique, nonlinguistic whole percepts, the present work suggests that episodic odor information is mediated by factors that can be subsumed under the rubric of semantic memory. Specific olfactory knowledge, such as perceived familiarity and identifiability, is strongly and positively related to episodic odor memory performance. In contrast to research using verbal and visual stimuli, proficiency in complex verbal intellectual abilities, such as vocabulary and fluency, seems to be of minor importance in memory for olfactory information. In agreement with earlier findings, this research indicates that episodic odor memory deteriorates across the adult life span. A similar negative age trend was observed for odor naming. Most importantly, statistical control of odor naming resulted in the elimination of age-related odor memory deficits. These results suggest that age-related failures in accessing specific semantic information of odors determine largely age-related deficits in episodic odor recognition.