title: Reduced capacity to sustain positive emotion in major depression reflects diminished maintenance of fronto-striatal brain activation.
abstract: Anhedonia, the loss of pleasure or interest in previously rewarding stimuli, is a core feature of major depression. While theorists have argued that anhedonia reflects a reduced capacity to experience pleasure, evidence is mixed as to whether anhedonia is caused by a reduction in hedonic capacity. An alternative explanation is that anhedonia is due to the inability to sustain positive affect across time. Using positive images, we used an emotion regulation task to test whether individuals with depression are unable to sustain activation in neural circuits underlying positive affect and reward. While up-regulating positive affect, depressed individuals failed to sustain nucleus accumbens activity over time compared with controls. This decreased capacity was related to individual differences in self-reported positive affect. Connectivity analyses further implicated the fronto-striatal network in anhedonia. These findings support the hypothesis that anhedonia in depressed patients reflects the inability to sustain engagement of structures involved in positive affect and reward.
authors.affiliation: Laboratory for Affective Neuroscience, Waisman Laboratory for Brain Imaging and Behavior, Department of Psychology, University of Wisconsin, Madison, WI 53705, USA.
authors.forename: Aaron S
authors.initials: AS
authors.lastname: Heller
authors.forename: Tom
authors.initials: T
authors.lastname: Johnstone
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Shackman
authors.forename: Sharee N
authors.initials: SN
authors.lastname: Light
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Peterson
authors.forename: Gregory G
authors.initials: GG
authors.lastname: Kolden
authors.forename: Ned H
authors.initials: NH
authors.lastname: Kalin
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Davidson
mesh_terms: D000328:Adult; D000339:Affect / Q000502:physiology; D016022:Case-Control Studies; D003865:Major Depressive Disorder / Q000503:physiopathology* / Q000523:psychology*; D004644:Emotions / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009714:Nucleus Accumbens / Q000503:physiopathology; D012201:Reward; D014793:Visual Cortex / Q000503:physiopathology*; D055815:Young Adult