Reinstatement of odour context cues veridical memories but not false memories.

The sense of smell has made a recent return to the forefront of research on episodic memory. Odour context cues can reactivate recently encoded memories during sleep-dependent memory consolidation [e.g., Rasch, B., Buchel, C., Gais, S., & Born, J. (2007). Odor cues during slow-wave sleep prompt declarative memory consolidation. Science, 315, 1426-1429], and reinstating the odour experienced during encoding at test results in superior recall and recognition [e.g., Isarida, T., Sakai, T., Kubota, T., Koga, M., Katayama, Y., & Isarida, T. K. (2014). Odor-context effects in free recall after a short retention interval: A new methodology for controlling adaptation. Memory & Cognition, 42, 421-433]. However, whether the impact of odour cues is restricted to the specific memories studied in the presence of the odour, or whether reinstating the odour also cues unstudied memories that are semantically related to the studied memories (i.e., false memories) is unknown. We used the Deese-Roediger-McDermott false memory paradigm to quantify the impact of odour cues on both veridical memory and false memory. Reinstating the odour presented during the study of the DRM word lists at the test phase resulted in better free recall of the studied words, but had no statistically significant impact on the number of false memories produced. We argue that odour cues influence recall of the memories they co-occurred with during study but potentially not semantically related memories.