Stress-Induced Inflammation and Reward Processing
Condition: Stress, Psychological
MeSH terms: Inflammation; Stress, Psychological
Study type: Interventional

Summary: 
      Anhedonia, or loss of interest or pleasure, is a key feature of depression and
      transdiagnostic construct in psychopathology. Both theory and compelling evidence from
      preclinical models implicates stress-induced inflammation as a key psychobiological pathway
      to anhedonic behavior; however, this pathway has not been demonstrated in human models.
      Further, although anhedonia may reflect dysregulation in multiple dimensions of reward, the
      extent to which stress-induced inflammation alters these dimensions is unclear. The current
      placebo controlled study used a standardized laboratory stressor task to elicit an
      inflammatory response in a sample of a healthy young women and evaluate effects of
      stress-induced inflammation on multiple behavioral indices of reward processing.
    

Detailed description: 
      In this study we propose to examine the association between psychosocial stress, the
      stress-induced inflammatory response, and reward processing in a female undergraduate sample.
      Specifically, we will 1) examine effects of an acute psychosocial stressor on reward
      processing; 2) evaluate the association between stress-related changes in inflammation and
      reward processing; and 3) test key vulnerability factors that may moderate the association
      between stress and reward. To achieve these goals, this study will recruit 60 female
      undergraduate students to test effects of stress on reward processing in a 3.5 hour
      laboratory session. Participants will be randomly assigned to either experience a laboratory
      stressor or a placebo control, and will complete reward tasks 90 minutes post stress/placebo
      onset, at which point the peripheral inflammatory response to stress reaches its peak. The
      reward tasks are computerized behavioral tasks that assess three domains of reward
      processing: reward-learning, reward motivation, and reward sensitivity. Throughout the
      session, all participants will complete self-report measures of affect and provide blood and
      saliva samples for evaluation of the psychological and physiological stress response. Within
      one week prior to the session, participants will attend a 1 hour visit in which they complete
      baseline reward tasks and self-report questionnaires assessing mood, personality, early life
      stress, and health behaviors. In total, participants will complete two visits, with a
      duration of 4.5 hours. This study builds upon prior studies demonstrating immediate effects
      of acute stress on reward processing, and further tests for delayed effects of acute stress
      on reward processing. Furthermore, this will be the first study to examine inflammation as a
      mechanism linking stress to deficits in reward processing. Findings may inform theory of
      depression etiology and contribute to more specialized treatment that is targeted at specific
      symptoms of depression.
    

Intervention name(s): Stress; Trier Social Stress Task; Placebo Trier Social Stress Task
Intervention type(s): Behavioral; Behavioral
Intervention description(s): Standardized acute psychosocial stressor; Active control version of the TSST
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Acute Psychosocial stress vs. Non-stress active control
Masking: Single (Participant)
Primary purpose: Basic Science
Keywords: reward processing