Are the Monday blues all in the mind? The role of expectancy in the subjective experience of mood

The role of expectations based on the Monday-blues stereotype was explored in self-reports of mood throughout the week. Participants (N = 66) were allocated to 3 matched groups. Expectations were manipulated in 2 experimental groups: 1 in support of Monday blues and 1 against them. All participants completed the Positive and Negative Affect Schedule (PANAS) daily for 2 weeks, and ranked the days of the week in terms of mood after completion. While there were no effects on negative affect, the pro-blues group reported lower positive affect on Monday. All 3 groups recalled Monday as the worst day in terms of mood. This suggests that expectations have subtle effects on the experience of Monday blues, and highlights the discrepancies between prospective and retrospective self-reports.