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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]

Abstract: The auditory processing of self-generated sounds is characterized by an attenuated vertex N1-component of the event-related potential (ERP) compared to the responses elicited by externally generated sounds. Typically, a motor condition where sounds are actively produced by button presses is compared with a passive listening condition. While this effect is usually interpreted as reflection of an internal forward model system, the impact of attention and arousal on the so called self-generation effect has not been systematically controlled in these studies: Is the auditory stimulation more attended during the active task compared to passive listening, e.g., caused by a higher arousal level? Or is it rather attended less and attention is drawn away from the task-irrelevant stimulation to the motor task? Accordingly, the self-generation effects reported in the literature can easily be over- or underestimated. In the present study we disentangled attention from the self-generation effect by introducing an active listening condition, in which attention is focused to the same feature as in the self-generation condition — the stimulus onset-to-onset interval. We observed a classical ‘self-generation effect’, i.e. attenuated amplitudes for self-generated compared to passive listened sounds at frontocentral electrodes. As expected this effect was overlapped by attention effects in space and time. However, topographical and tomographical analyses allowed us to clearly disentangle both effects. Our results argue for the existence of a genuine self-generation effect, but emphasize the problem of possible over- or underestimation caused by attentional confounds. [Copyright &y& Elsevier]

Abstract: Binocular rivalry occurs when dissimilar images are presented to corresponding retinal regions of the two eyes: visibility alternates irregularly between the two images, interspersed by brief transitions when parts of both may be visible. We measured event-related potentials (ERPs) following binocular rivalry by changing the stimulus viewed by one eye to be identical to that in the other eye, eliciting binocular fusion. Because of the rivalry, observers either saw the change, when it happened to the visible stimulus, or did not see the change, when it happened to the invisible stimulus. The earliest ERP differences between visible and invisible changes occurred after about 100ms (P1) when the rivalry was between stimuli differing in orientation, and after about 200ms (N1) when the rivalry was between stimuli differing in colour. These differences originated from ventro-lateral temporal and prefrontal areas. We conclude that the rivalling stimulus property influences the timing of modulation of correlates of visual awareness in a property-independent cortical network. [Copyright &y& Elsevier]