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Background There is amassing evidence that risky decision-making in bipolar disorder is related to reward-based differences in frontostriatal regions. However, the roles of early attentional and later cognitive processes remain unclear, limiting theoretical understanding and development of targeted interventions. Methods Twenty euthymic bipolar disorder and 19 matched control participants played a Roulette task in which they won and lost money. Event-related potentials and source analysis were used to quantify predominantly sensory-attentional (N1), motivational salience (feedback-related negativities [FRN]), and cognitive appraisal (P300) stages of processing. We predicted that the bipolar disorder group would show increased N1, consistent with increased attentional orienting, and reduced FRN, consistent with a bias to perceive outcomes more favorably. Results As predicted, the bipolar disorder group showed increased N1 and reduced FRN but no differences in P300. N1 amplitude was additionally associated with real-life risk taking, and N1 source activity was reduced in visual cortex but increased activity in precuneus, frontopolar, and premotor cortex, compared to those of controls. Conclusions These findings demonstrate an early attentional bias to reward that potentially drives risk taking by priming approach behavior and elevating reward salience in the frontostriatal pathway. Although later cognitive appraisals of these inputs may be relatively intact in remission, interventions targeting attention orienting may also be effective in long-term reduction of relapse. [ABSTRACT FROM AUTHOR]

Background: Hypomania is associated with impulsive decision making and risk taking, characteristics that may arise from hypersensitivity to reward. To date, the neural dynamics underlying intertemporal reward processing have neither been characterized clinically nor in the general population. Taking vulnerability to hypomania as a surrogate model of impulsivity, we utilized event-related potentials to study the neural mechanisms of delay discounting. Methods: In the first experiment, 32 participants completed an established Two Choice Impulsivity Paradigm in which free choice between immediate and delayed rewards was used to quantify impulsivity behaviorally. In the second experiment, electroencephalography was recorded while 32 separately recruited participants completed a speeded response task involving gains and losses of monetary incentives to be paid at three different delays after the experiment. Results: In the first experiment, the hypomania-prone group made significantly more immediate choices than the control group. In the second experiment, the hypomania-prone group evidenced greater differentiation between delayed and immediate outcomes in early attention-sensitive (N1) and later reward-sensitive (feedback-related negativity) components. Proneness to hypomania was also associated with greater N1 amplitude to rewards per se. Conclusions: These results indicate steeper delay discounting in hypomania at multiple stages of information processing. The N1 modulation by valence and delay suggests an attentional bias to immediate rewards, which may drive subsequent cognitive appraisal of outcomes (feedback-related negativity). These results highlight the early influence of attention on reward processing and provide support for reward dysregulation accounts of bipolar disorder. Potential implications for mindfulness training and other therapeutic interventions are highlighted. [Copyright &y& Elsevier]