Abstract
The Reward Hypersensitivity Model of bipolar disorder argues that hypersensitivity to reward-relevant cues characterizes risk for hypo/mania. This hypersensitivity leads to increased goal-directed motivation during reward-relevant life events that, in the extreme, is reflected in hypo/manic symptoms. In line with this perspective, individuals with bipolar disorder display elevated activation in a cortico-striatal reward circuit including the nucleus accumbens (NAcc) and medial orbitofrontal cortex (mOFC). To date, however, research on reward-related neural circuitry underlying bipolar symptoms focuses on syndromal bipolar disorder (bipolar I, bipolar II), and typically examines neural regions in isolation of each other. Accordingly, this study examines the relationship between subsyndromal hypo/mania proneness and structural connectivity between the NAcc and both the mOFC and amygdala in a medication-free sample. Fifty-four community participants completed diffusion-weighted imaging and a self-report measure of bipolar risk (hypo/mania proneness). As predicted, elevated structural connectivity between the NAcc and both the mOFC and amygdala were associated with elevated hypo/ mania proneness. This relationship was specific to NAcc-centered reward connectivity, as there was no relationship between hypo/mania proneness and either whole-brain or cortico-amygdala connectivity. Results suggest that rewardrelevant tractography from cortical (mOFC) and subcortical (amygdala) regions amplify NAcc-centered reward processing in bipolar risk.
Original language | English (US) |
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Pages (from-to) | 928-936 |
Number of pages | 9 |
Journal | Social cognitive and affective neuroscience |
Volume | 12 |
Issue number | 6 |
DOIs | |
State | Published - Jun 1 2017 |
Funding
We would like to thank Todd Parrish, Mutahir Rauf, Sandra Shi and Rita Taylor for their assistance with MRI data acquisition. This work was supported by the National Institute of Mental Health [2T32MH067564 to K.S.D., R01 MH100117-01 to R.N., R01 MH077908-01A1 to R.N.]; the Ryan Licht Sang Bipolar Foundation [Young Investigator Grant and Independent Investigator Grant to R.N.]; the Chauncey and Marion D. McCormick Family Foundation [Young Investigator Grant and Independent Investigator Grant to R.N.]; and the National Science Foundation Graduate Research Fellowship Program [DGE-0824162 to C.B.Y.].
Keywords
- Amygdala
- Diffusion tensor imaging
- Hypomania/mania
- Medial orbitofrontal cortex
- Nucleus accumbens
- Reward processing
ASJC Scopus subject areas
- Experimental and Cognitive Psychology
- Cognitive Neuroscience