title: Do depressive symptoms "blunt" effort? An analysis of cardiac engagement and withdrawal for an increasingly difficult task.
abstract: Research on depression and effort has suggested "depressive blunting"-lower cardiovascular reactivity in response to challenges and stressors. Many studies, however, find null effects or higher reactivity. The present research draws upon motivational intensity theory, a broad model of effort that predicts cases in which depressive symptoms should increase or decrease effort. Because depressive symptoms can influence task-difficulty appraisals-people see tasks as subjectively harder-people high in depressive symptoms should engage higher effort at objectively easier levels of difficulty but also quit sooner. A sample of adults completed a mental effort challenge with four levels of difficulty, from very easy to difficult-but-feasible. Depressive symptoms were assessed with the CESD and DASS; effort-related cardiac activity was assessed via markers of contractility (e.g., the cardiac pre-ejection period [PEP]) obtained with impedance cardiography. The findings supported the theory's predictions. When the task was relatively easier, people high in depressive symptoms showed higher contractility (shorter PEP), consistent with greater effort. When the task was relatively harder, people high in depressive symptoms showed diminished contractility, consistent with quitting. The results suggest that past research has been observing a small part of a larger trajectory of trying and quitting, and they illustrate the value of a theoretically grounded analysis of depressive symptoms and effort-related cardiac activity.
authors.affiliation: Department of Psychology, University of North Carolina at Greensboro, United States. Electronic address: p_silvia@uncg.edu.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Silvia
authors.affiliation: Department of Psychology, University of North Carolina at Greensboro, United States.
authors.forename: Zuzana
authors.initials: Z
authors.lastname: Mironovová
authors.affiliation: Department of Psychology, University of North Carolina at Greensboro, United States.
authors.forename: Ashley N
authors.initials: AN
authors.lastname: McHone
authors.affiliation: Department of Psychology, University of North Carolina at Greensboro, United States.
authors.forename: Sarah H
authors.initials: SH
authors.lastname: Sperry
authors.affiliation: Department of Psychology, University of North Carolina at Greensboro, United States.
authors.forename: Kelly L
authors.initials: KL
authors.lastname: Harper
authors.affiliation: Department of Psychology, University of North Carolina at Greensboro, United States.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Kwapil
authors.affiliation: Department of Psychology, University of North Carolina at Greensboro, United States.
authors.forename: Kari M
authors.initials: KM
authors.lastname: Eddington
mesh_terms: D000328:Adult; D002307:Cardiography, Impedance; D003863:Depression / Q000503:physiopathology* / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008960:Models, Psychological; D009042:Motivation / Q000502:physiology*; D009200:Myocardial Contraction / Q000502:physiology*; D013647:Task Performance and Analysis; D055815:Young Adult
keywords: Anhedonia; Depression; Effort; Impedance cardiography; Motivation; Self-regulation