Microdosing psychedelics-Does it have an impact on emodiversity?

Background and aims: Previous research has proposed that microdosing, i.e., the repeated use of sub-threshold doses of serotonergic hallucinogens, has an impact on mood by increasing emotional awareness. We propose that increased emotional awareness could translate into higher emodiversity, a balanced experience of emotions in which emotions are experienced with more similarity in intensity and duration. We examine the effect of microdosing, the day after, as well as the cumulative effect of microdosing on overall, positive and negative emodiversity. Methods: We use data collected over a period of 28 days sampled between February to June 2020 from 18 users that already had an active practice of microdosing at the start of the data collection. We assessed emotional states using ESM methods, i.e., signal-contingent sampling with triggers sent 5 times a day. The working dataset has a number of 224 observations days. We used mixed effects models to test our hypotheses. Results: When taking into account the level of average affect, we found that during microdosing days positive and overall emodiversity were significantly lower. No evidence was found for a mediating role of the level of average affect. Higher cumulative instances of microdosing were not related to any of the emodiversity indexes. Participants experienced more "awe, wonder, or amazement", "ashamed, humiliated, or disgraced" as well as less "joyful, glad, or happy" emotions during microdosing days. Conclusion: A microdosing practice may increase the centrality of certain emotions on microdosing days, resulting in a decrease in emotional diversity.