Investigating the Correspondence between Accuracy, Confidence, and Metacognitive Insight for Olfactory Processing

Olfaction is an important yet relatively often overlooked sense, relevant to cognition, emotion, mental health, and ageing. Research into sensory domains such as interoception indicates discrepancies between behaviourally assessed accuracy and self-report measures, such as confidence. Initial evidence suggests a similar discrepancy between behavioural and self-report measures may also be present for olfaction. This study employed a multidimensional framework to examine the relationships among behavioural accuracy, self-reported confidence, and metacognitive insight for olfactory processing, using the Sniffin' Sticks Test across three olfactory tasks: threshold, discrimination, and identification. Participants exhibited varying metacognitive insight into their olfactory performance, with insight being significantly lower for the threshold task. In a complementary analysis, accuracy and confidence were not related in the threshold task, but were aligned during both the discrimination and identification tasks. These results suggest that individuals who have the most sensitive olfactory threshold performance do not display corresponding high levels of confidence, supporting the finding of reduced insight for this type of olfactory task specifically. Across tasks, behavioural accuracy was related in all tasks, as was self-reported confidence. However, metacognitive insight was not associated across tasks. Together, these results highlight that metacognitive insight for olfactory ability may differ depending on the type of olfactory task. These initial findings require replication with alternative methods to account for differences in task performance, and further investigation to ascertain patterns of results in old age where there can be a decline in olfactory function. A more comprehensive understanding of olfactory processing across accuracy, self-report, and insight measures, across a range of different olfactory tests, may provide further insight into the relationship between specific aspects of olfactory ability and how these might relate to mental health and neurological conditions.