|
Abstract
|
BACKGROUND: Repetitive Negative Thinking (RNT) is a symptom dimension of depression that is associated with a poorer prognosis in terms of higher recurrence, treatment resistance, residual symptoms, and disability. This investigation examined whether RNT is associated with aberrant reward processing and fear learning.
METHODS: Very High RNT [n=60] and High RNT [n=60] propensity-matched individuals with depression (age, sex, race/ethnicity, income/employment, body mass index, depressive and anxiety symptom severity) participated in the present study along with matched healthy comparison (HC) volunteers [n=30]. This propensity-matched sample was selected from the larger Tulsa-1000 study. Participants performed two functional magnetic resonance imaging tasks: the Monetary Incentive Delay task (MID) probing reward processing and the Fear Conditioning task probing aversive learning and extinction.
RESULTS: Both very high and high RNT groups (VH-RNT, H-RNT) showed lower neural activity than HC in reward circuitry including inferior frontal gyrus (VH-RNT: β = -1.24, H-RNT: β = -1.28) as well as the cerebellum (VH-RNT: β = -0.93, H-RNT: β = -1.14). However, individuals with VH-RNT exhibited lower activation than H-RNT in central autonomic network components during fear conditioning (β: -0.84) as well as continued conditioned responses during early extinction in the postcentral cortex (β: 0.71).
CONCLUSION: VH-RNT showed aberrant processing in fear conditioning during both learning and extinction phases, compared to H-RNT. These findings demonstrate that dysfunctions of negative valence associated with RNT may be domain-specific, which should be taken into account for identifying potential specific targets of intervention.
Language: en |