Achieving Olfactory Expertise: Training for Transfer in Odor Identification

Human olfactory function requires the identification of everyday odors. A characteristic feature of olfaction is that most people find it hard to identify and name common odors, and when odors are presented simultaneously in mixtures, performance is even further compromised. Few studies have systematically assessed how training might enhance identification of single odors and mixtures. This study compared how odor identification training with either single odors or binary mixtures affected identification performance, as well as transfer effects to untrained tasks and odors. Twenty-seven healthy participants (22 F; 28.0 ± 4.7 years old) completed identification training of 8 odors using a list of 16 veridical names. The study included 8 training sessions, as well as pretest and posttest evaluations. Results suggest notable effects of learning, as well as transfer to novel tasks and odors. Overall, training with single odors led to slightly better results than the binary mixture condition, suggesting that in novices, odor identification may be facilitated via consolidation of single odor objects, before learning to dissociate binary mixtures. Overall, odor identification may be trained to generate transfer of learning, although transfer effects were observed in both training methods. Our work suggests that odor identification abilities, while often limited, are highly trainable.