Depressed individuals take less joy in surprising good outcomes

A study conducted on college students in Florida found that individuals with depression experience less joy from surprising positive outcomes compared to non-depressed individuals. When these students received better grades on a midterm exam than they expected, their positive emotional responses were diminished. However, their negative emotional responses to receiving a lower grade than anticipated were as strong as those of non-depressed students. The study was published in Psychological Medicine.

Depression is a common and serious mental health disorder characterized by persistent feelings of sadness, hopelessness, and a lack of interest or pleasure in activities. It affects how a person thinks, feels, and behaves, sometimes leading to physical symptoms such as changes in appetite, sleep disturbances, and fatigue. Depression can impair daily functioning, relationships, and work performance, making even simple tasks feel overwhelming. It is more than a temporary emotional reaction to life events and often requires professional treatment.

Statistics indicate that depression affects approximately 7% of people in the United States annually. It is one of the leading causes of disability worldwide. On average, a person has around a 20% chance of developing depression at some point in their life.

Study authors William J. Villano and Aaron S. Heller aimed to explore how individuals with depression emotionally respond to personally significant life events. Since depression is a mood disorder, it was hypothesized that depressed individuals would exhibit dysregulated emotional reactions.

To better understand this phenomenon, the researchers examined students’ reactions to their midterm exam grades in introductory chemistry courses. These grades represent recurring yet highly meaningful events for students, as their final grades primarily depend on midterm performance. Low final grades can potentially hinder students’ academic and career aspirations.

The study involved 724 undergraduate students enrolled in general and organic chemistry courses at the University of Miami, with an average age of 19 years. Of the participants, 539 were women. Students agreed to complete surveys using their phones multiple times throughout the semester, sometimes several times per day. By the study’s conclusion, 687 participants had completed all surveys, with one-third qualifying as depressed.

At the start of the semester and at multiple points between exams, participants completed assessments for depression and anxiety symptoms using the Generalized Anxiety Disorder-7 (GAD-7) and the Patient Health Questionnaire (PHQ-9). Every two days, they also completed assessments of their current emotional state using the Positive and Negative Affect Schedule (PANAS). A messaging app sent SMS notifications with survey links at planned intervals.

After taking the midterm exam, students predicted their grades. Once their grades were released, the app prompted students to complete emotional assessments every 45 minutes over the following eight hours. Researchers calculated the difference between predicted and actual grades to evaluate emotional responses to positive and negative outcomes.

To control the process, students decided when to view their grades. They received SMS notifications indicating their grades were available and could click a provided link to view them. Once a student accessed their grade, the app automatically triggered the corresponding emotional surveys.

On average, each participant completed 81–82 surveys during the study period, responding to 72% of the surveys sent. Overall, students tended to slightly overestimate their grades. Participants with more severe depression symptoms reported lower grade expectations and achieved marginally lower actual grades.

As expected, students who received better grades than anticipated experienced mood improvements, while those who received lower grades reported worsened moods. These emotional changes persisted for seven to eight hours after viewing their grades.

However, among depressed students, the mood improvement in response to better-than-expected grades was significantly less pronounced compared to non-depressed students. Conversely, there was no difference in mood worsening between depressed and non-depressed students when grades were lower than expected. Anxiety levels also showed no significant association with emotional responses to grades.

“Using a high-stakes, personally impactful, real-world event coupled with experience sampling of emotion, we found that individuals with higher levels of depression displayed an attenuated emotional response to positive PEs [positive prediction errors, when students got better grades than they expected]. These effects were highly specific and suggest that anhedonia [reduced ability to feel pleasure and enjoyment] may manifest due to individuals discounting the meaning of positive PEs as a sort of maladaptive cognitive immunization,” the study authors concluded.

While the study provides valuable insights into the emotional reactions of individuals with depression, its findings are limited to a specific group of students in a particular context. Results may differ in other demographic groups or in response to different mood-impacting situations. Further research is needed to understand how depression affects emotional responses across diverse settings.

The paper, “Depression is associated with blunted affective responses to naturalistic reward prediction errors,” was authored by William J. Villano and Aaron S. Heller.