The Sweet Taste Test: Relationships with Anhedonia Subtypes, Personality Traits, and Menstrual Cycle Phases

A better understanding of the etiology and pathology related to distinct subtypes of anhedonia can lead to more efficacious personalized treatments. The current study advances knowledge on consummatory anhedonia - represented in the Research Domain Criteria (RDoC) subconstruct of Initial Response to Reward (IRR). The Sweet Taste Test (STT) has promise as a behavioral paradigm for IRR, as it is sensitive to manipulation of mu-opioid receptors. However, there is a lack of existing knowledge of how the STT relates to subtypes of anhedonia, personality traits, and phases of the menstrual cycle. To address these questions, we administered the STT to 72 nonpsychiatric adults (76% women; mean age: 19.11). As predicted, the hedonic slope reflecting increasing "like" ratings over increasing concentrations of five sucrose solutions (ranging from 0.05 M to 0.86 M), was lower in individuals reporting higher consummatory anhedonia (measured with Temporal Experience of Pleasure Scales - Consummatory Subscale) and in women in the mid-to-late luteal menstrual phase (days 20 to 28). Both effects were driven by lower hedonic ratings to the sweetest concentration. The hedonic slope was larger in individuals scoring higher on the Flight-Freeze-Avoidance System personality factor from the Reinforcement Sensitivity Theory Personality Questionnaire - driven by lower hedonic ratings for the least sweet concentration. No factor or aspect from the Big Five Aspects Scale related to hedonic ratings on the STT. The STT may be a valid and specific standardized behavioral paradigm to add to IRR, particularly if validated in a large transdiagnostic psychiatric sample.