Individual differences in circadian variations of consumers' emotional state.

A laboratory study investigated the effect of circadian orientation on consumers' emotional state at different times of day. Subjects' emotional state was measured using the Pleasure-Arousal-Dominance scale in the morning and in the evening. Individual circadian orientation (morningness-eveningness) was also assessed. Analyses showed that changes in consumers' emotional state as a function of the time of the day is moderated by individual differences in circadian orientation. Morning-types were in a more pleasurable emotional state in the morning than in the evening. The predicted reversed pattern for the evening-types did not reach significance. Null effects were reported for the arousal and submissive/dominance dimensions of emotional state. Morning-types rated themselves as more awake than evening-types. Morning-types were more awake in the morning than in the evening and vice-versa for evening-types. The magnitude of the differences between evening-type and morning-type individuals was significant in the morning. Findings are discussed from methodological, theoretical, and marketing perspectives.