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Background Blunted neural reward responsiveness (RR) is observed in youth depression. However, it is unclear whether symptoms of depression experienced early in development relate to adolescent RR beyond current symptoms and, further, whether such relationships with RR differ during two key components of reward processing: anticipation and outcome. Methods Within a prospective longitudinal study oversampled for early depression, children and caregivers completed semiannual diagnostic assessments beginning in preschool. In later adolescence, mean age = 16.49 years (SD = 0.94), youths’ (N = 100) neurophysiological responses to cues signaling likely win and loss and these outcomes were assessed. Longitudinally assessed dimensional depression and externalizing symptoms (often comorbid with depression as well as associated with RR) experienced at different developmental periods (preschool [age 3–5.11 years], school age [6–9.11 years], early adolescence [10–14.11 years], current) were used as simultaneous predictors of event-related potentials indexing anticipatory cue processing (cue-P3) and outcome processing (reward positivity/feedback negativity and feedback-P3). Results Blunted motivated attention to cues signaling likely win (cue-P3) was specifically predicted by early-adolescent depression symptoms. Blunted initial response to win (reward positivity) and loss (feedback negativity) outcomes was specifically predicted by preschool depression symptoms. Blunted motivational salience of win and loss outcomes (feedback-P3) was predicted by cumulative depression, not specific to any developmental stage. Conclusions Although blunted anticipation and outcome RR is a common finding in depression, specific deficits related to motivated attention to cues and initial outcome processing may map onto the developmental course of these symptoms.

Individuals at risk for schizophrenia-spectrum disorders display abnormalities related to motivational salience, or the ability of stimuli to elicit attention due to associations with rewards or punishments. However, the nature of these abnormalities is unclear because most focus on responses to stimuli from broad “pleasant” and “unpleasant” categories and ignore the variation of motivational salience within these categories. In two groups at risk for schizophrenia-spectrum disorders—a Social Anhedonia group and a Psychotic-like Experiences group—and a control group, the current study examined event-related potential components sensitive to motivational salience—the Early Posterior Negativity (EPN), reflecting earlier selective attention, and the Late Positive Potential (LPP), reflecting sustained attention. Compared to controls, the Social Anhedonia group showed smaller increases in the EPN in response to erotica and smaller increases in the LPP as the motivational salience of pleasant images increased (excitinglarger increases in LPP amplitudes as the motivational salience of pleasant images increased. Also, both at-risk groups showed larger increases in the LPP to threatening images but smaller increases to mutilation images. These findings suggest that examining abnormalities beyond those associated with broad categories may be a way to identify mechanisms of dysfunction.

Perceived control is a fundamental psychological function that can either boost positive affect or buffer negative affect. The current study addressed the electrophysiological correlates underlying perceived control, as exercised by choice, in the processing of feedback valence. Thirty-six participants performed an EEG choice task during which they received positive or negative feedback following choices made either by themselves or by a computer. Perceived control resulted in an enhanced reward positivity for positive feedback but increased theta power for negative feedback. Further, perceived control led to greater feedback P3 amplitude and delta power, regardless of feedback valence. These results suggest functional heterogeneity of perceived control in feedback processing as diverse as magnifying the reward signal, enhancing the need for control and increasing the motivational salience of outcome irrespective of valence.

Cognitive architectures tasked with swiftly and adaptively processing biologically important events are likely to classify these on two central axes: motivational salience, that is, those events’ importance and unexpectedness, and motivational value, the utility they hold, relative to that expected. Because of its temporal precision, electroencephalography provides an opportunity to resolve processes associated with these two axes. A focus of attention for the last two decades has been the feedback-related negativity (FRN), a frontocentral component occurring 240–340 ms after valenced events that are not fully predicted. Both motivational salience and value are present in such events and competing claims have been made for which of these is encoded by the FRN. The present study suggests that motivational value, in the form of a reward prediction error, is the primary determinant of the FRN in active contexts, while in both passive and active contexts, a weaker and earlier overlapping motivational salience component may be present.

Pavlovian-to-instrumental transfer (PIT) refers to a phenomenon whereby a classically conditioned stimulus (CS) impacts the motivational salience of instrumental behavior. We examined behavioral response patterns and functional magnetic resonance imaging (fMRI) based effective connectivity during an avoidance-based PIT task. Eleven participants (8 females, Mage = 28.2, SD = 2.8, range = 25–32 years) completed the task. Effective connectivity between a priori brain regions engaged during the task was determined using hemodynamic response function group iterative multiple model estimation (HRF-GIMME). Participants exhibited behavior that was suggestive of specific PIT, a CS previously associated with a reinforcing outcome increased instrumental responding directed at the same outcome. We did not find evidence for general PIT, a CS did not significantly increase instrumental responding towards a different but related outcome. Using HRF-GIMME, we recovered effective connectivity maps among corticostriatal circuits engaged during the task. Group-level paths revealed directional effects from left putamen to right insula and from right putamen to right cingulate. Importantly, a direct effect of specific PIT stimuli on blood–oxygen-level-dependent (BOLD) activity in the left putamen was found. Results provide initial evidence of effective connectivity in key brain regions in an avoidance-based PIT task network. This study adds to the literature studying PIT effects in humans and employing GIMME models to understand how psychological phenomena are supported in the brain.

Introduction There is mixed evidence about emotional processing abnormalities in schizophrenia and schizoaffective disorder, with self-reports and clinician ratings indicating significant differences between patients and controls, but studies of in-the-moment, self-reported emotional experience finding only small differences between these groups. The current meta-analysis synthesizes statistics from studies measuring the P3 and LPP, two event-related potential (ERP) components sensitive to attentional allocation, to examine whether patients exhibit ERP response abnormalities to neutral and valenced visual stimuli. Methods Standardized mean amplitudes and standard errors of P3 and/or LPP waveforms (300–2000 ms) in response to neutral and valenced images were calculated for 13 studies (total n = 339 individuals with schizophrenia, 331 healthy controls). Results In response to neutral images, there were very small, non-significant differences in ERP amplitudes between patient and control groups (k = 9; Hedges' g = −0.06, 95% CI: −055, 0.43, p = 0.81). In contrast, patients showed a small, significant reduction in ERP amplitudes compared to controls in response to negative images (k = 13; Hedges' g = −0.32, 95% CI: −0.59, −0.05, p = 0.02) and a small, but nonsignificant, reduction in amplitudes in response to positive images (k = 7; Hedges' g = −0.27, 95% CI: −0.71, 0.18, p = 0.24). Conclusions and implications The current review indicates that compared to controls, patients have slightly diminished P3 and LPP amplitudes in response to positive and negative stimuli. This small reduction may reflect decreased attention allocation, possibly indicating an abnormality during a distinct stage of early processing related to evaluating the motivational salience of a stimulus.

В настоящем обзоре представлен анализ данных литературы, посвященных исследованиям нейросети салиенса, динамике формирования нейросети в процессе онтогенеза головного мозга, дисрегуляции салиенса при нейродегенеративных и нейропсихических расстройствах. Рассмотрена роль дофаминергического дисбаланса в формировании аберрантного салиенса при шизофрении. Отдельное внимание уделено исследованиям значения мотивационного салиенса, и системы вознаграждения в патогенезе аддиктивных расстройств., This review presents an analysis of the literature on studies of the salience neural network, the dynamics of neural network formation during ontogenesis of the brain, and salience dysregulation in neurodegenerative and neuropsychiatric disorders. The role of dopaminergic imbalance in the formation of aberrant salience in schizophrenia is considered. Particular attention is paid to the studies of the significance of motivational salience and reward system in the pathogenesis of addictive disorders.

Rewarding and aversive outcomes have opposing effects on behaviour, facilitating approach and avoidance, although we need to accurately anticipate each type of outcome in order to behave effectively. Attention is biased toward stimuli that have been learned to predict either type of outcome, and it remains an open question whether such orienting is driven by separate systems for value- and threat-based orienting or whether there exists a common underlying mechanism of attentional control driven by motivational salience. Here we provide a direct comparison of the neural correlates of value- and threat-based attentional capture following associative learning. Across multiple measures of behaviour and brain activation, our findings overwhelmingly support a motivational salience account of the control of attention. We conclude that there exists a core mechanism of experience-dependent attentional control driven by motivational salience, and that prior characterisations of attention as being value-driven or supporting threat monitoring need to be revisited.

The ability to recognize motivationally salient events and adaptively respond to them is critical for survival. Here, we tested whether dopamine (DA) neurons in the dorsal raphe nucleus (DRN) contribute to this process in both male and female mice. Population recordings of DRNDAneurons during associative learning tasks showed that their activity dynamically tracks the motivational salience, developing excitation to both reward-paired and shock-paired cues. The DRNDAresponse to reward-predicting cues was diminished after satiety, suggesting modulation by internal states. DRNDAactivity was also greater for unexpected outcomes than for expected outcomes. Two-photon imaging of DRNDAneurons demonstrated that the majority of individual neurons developed activation to reward-predicting cues and reward but not to shock-predicting cues, which was surprising and qualitatively distinct from the population results. Performing the same fear learning procedures in freely-moving and head-fixed groups revealed that head-fixation itself abolished the neural response to aversive cues, indicating its modulation by behavioral context. Overall, these results suggest that DRNDAneurons encode motivational salience, dependent on internal and external factors.SIGNIFICANCE STATEMENTDopamine (DA) contributes to motivational control, composed of at least two functional cell types, one signaling for motivational value and another for motivational salience. Here, we demonstrate that DA neurons in the dorsal raphe nucleus (DRN) encode the motivational salience in associative learning tasks. Neural responses were dynamic and modulated by the animal's internal state. The majority of single-cells developed responses to reward or paired cues, but not to shock-predicting cues. Additional experiments with freely-moving and head-fixed mice showed that head-fixation abolished the development of cue responses during fear learning. This work provides further characterization on the functional roles of overlooked DRNDApopulations and an example that neural responses can be altered by head-fixation, which is commonly used in neuroscience.

Background: Although previous studies have shown an inverse relation between life meaning and eating disorder symptoms, the correlational nature of this evidence precludes causal inferences. Therefore, this study used an experimental approach to test the causal impact of life meaning on individuals' weight and shape concerns.Methods: Female students at risk for developing an eating disorder (N = 128) were randomly assigned to the control or the meaning condition, which involved thinking about and committing to pursue intrinsically valued life goals. A color-naming interference task was used to assess the motivational salience of body-related stimuli, and self-report measures were used to assess participants' overvaluation of weight and shape.Results: The meaning manipulation was effective in activating intrinsically valued life goals. However, it did not result in lower self-reported overvaluation of weight and shape or lower color-naming interference effects of body-related stimuli, compared to the control condition. Post-hoc analyses suggested that baseline meaning in life was related to the impact of the manipulation.Conclusions: This experimental study did not provide evidence for a causal influence of life meaning on the overvaluation of weight and shape in a high-risk group. The current findings suggest that we first need to examine the relationship between life meaning and eating disorder symptoms in more detail, before implementing brief meaning manipulations in clinical practice.

The allocation of attention can be modulated by the emotional value of a stimulus. In order to understand the biasing influence of emotion on attention allocation further, we require an animal test of how motivational salience modulates attention. In mice, female odour triggers arousal and elicits emotional responses in males. Here, we determined the extent to which objects labelled with female odour modulated the attention of C57BL/6J male mice. Seven experiments were conducted, using a modified version of the spontaneous Novel Object Recognition task. Attention was operationalised as differential exploration time of identical objects that were labelled with either female mouse odour (O+), a non-social odour, almond odour (Oa) or not labelled with any odour (O-). In some experiments we tested trial unique (novel) objects than never carried an odour (X-). Using this novel object preference test we found that when single objects were presented, as well as when two objects were presented simultaneously (so competed with each other for attention), O+ received preferential attention compared to O-. This result was independent of whether O+ was at a novel or familiar location. When compared with Oa at a novel location, O+ at a familiar location attracted more attention. Compared to X-, O+ received more exploration only when placed at a novel location, but attention to O+ and X- was equivalent when they were placed in a familiar location. These results suggest that C57BL/6J male mice weigh up aspects of odour, object novelty and special novelty for motivational salience, and that, in some instances, female odour elicits more attention (object exploration) compared to other object properties. The findings of this study pave the way to using motivationally-significant odours to modulate the cognitive processes that give rise to differential attention to objects.

How can animals behave effectively in conditions involving different motivational contexts? Here, we propose how reinforcement learning neural networks can learn optimal behavior for dynamically changing motivational salience vectors. First, we show that Q-learning neural networks with motivation can navigate in environment with dynamic rewards. Second, we show that such networks can learn complex behaviors simultaneously directed towards several goals distributed in an environment. Finally, we show that in Pavlovian conditioning task, the responses of the neurons in our model resemble the firing patterns of neurons in the ventral pallidum (VP), a basal ganglia structure involved in motivated behaviors. We show that, similarly to real neurons, recurrent networks with motivation are composed of two oppositely-tuned classes of neurons, responding to positive and negative rewards. Our model generates predictions for the VP connectivity. We conclude that networks with motivation can rapidly adapt their behavior to varying conditions without changes in synaptic strength when expected reward is modulated by motivation. Such networks may also provide a mechanism for how hierarchical reinforcement learning is implemented in the brain., Added the Methods section

Purpose: The purpose of the article is a presentation and an analysis of research on motivational salience and satisfaction with training in the field of security and defense that was carried out with the assistance of a number of universities and academies in Europe. Method: Survey research and statistical analysis including, and certain statistical methods were applied for processing of the grouped statistical data, their interpretation and offering of the relevant decisions. Results: The study attempts to outline the foundation of the methodology for conducting research on motivational salience and its relation with satisfaction in security and defense training, following the example of higher education institutions in Europe. The research findings are characterized by the scale of scientific and practical research and covering 19 educational institutions in the field of security and defense in Europe. The research is distinguished by the presence of a scientific subject not only at the national level but also at the international level. The results are in the area of interest to the academic staff of the military universities and academies of Austria, Belgium, Bulgaria, Estonia, Spain, Lithuania, Poland, Portugal, Romania, Slovakia, the Netherlands, the Czech Republic, Sweden, Switzerland, and others. Conlusion/findings: The study was discussed at the extended scientific board of the Logistics of the Security Department at the Vasil Levski National Military University in Bulgaria. The thesis that has been elaborated as a result of carried out works was the subject of the defense in the Security and Defence area of higher education in Bulgaria.

The ability to recognize motivationally salient events and respond to them adaptively is critical for survival. Here we tested whether dopamine (DA) neurons in the dorsal raphe nucleus (DRN) contribute to this process. Population recordings of DRNDA neurons during associative learning tasks showed that their activity dynamically tracks salience, developing excitation to both reward- and punishment-paired cues. The DRNDA response to reward-predicting cues was diminished after satiety, suggesting modulation by internal states. DRNDA activity was also greater for unexpected outcomes than for expected outcomes. Two-photon imaging of DRNDA neurons demonstrated that the majority of individual neurons developed activation to reward-predicting cues but not to punishment-predicting cues, which was surprising and qualitatively distinct from the population results. Head-fixation during fear learning abolished the neural response to aversive cues, indicating modulation by behavioral context. Overall, these results suggest that DRNDA neurons encode motivational salience, dependent on internal and external factors.

Background: Binge Drinking (BD), a highly prevalent drinking pattern among youth, has been linked with anomalies in inhibitory control. However, it is still not well characterized whether the neural mechanisms involved in this process are compromised in binge drinkers (BDs). Furthermore, recent findings suggest that exerting inhibitory control to alcohol-related stimuli requires an increased effort in BDs, relative to controls, but the brain regions subserving these effects have also been scarcely investigated. Here we explored the impact of BD on the pattern of neural activity mediating response inhibition and its modulation by the motivational salience of stimuli (alcohol-related content). Methods: Sixty-seven (36 females) first-year university students, classified as BDs (n = 32) or controls (n = 35), underwent fMRI as they performed an alcohol-cued Go/NoGo task in which pictures of alcoholic or non-alcoholic beverages were presented as Go or NoGo stimuli. Results: During successful inhibition trials, BDs relative to controls showed greater activity in the bilateral inferior frontal gyrus (IFG), extending to the anterior insula, a brain region usually involved in response inhibition tasks, despite the lack of behavioral differences between groups. Moreover, BDs displayed increased activity in this region restricted to the right hemisphere when inhibiting a prepotent response to alcohol-related stimuli. Conclusions: The increased neural activity in the IFG/insula during response inhibition in BDs, in the absence of behavioral impairments, could reflect a compensatory mechanism. The findings suggest that response inhibition-related activity in the right IFG/insula is modulated by the motivational salience of stimuli and highlight the role of this brain region in suppressing responses to substance-associated cues. This investigation was supported by grants from the Spanish Ministerio de Sanidad, Servicios Sociales e Igualdad, Plan Nacional sobre Drogas (PNSD 2015/034), Ministerio de Economía y Competitividad (PSI2015-70525-P) co-funded for European Regional Development Fund and Xunta de Galicia (GRC ED431C 2017/06). SS-S was supported by a predoctoral fellowship from the Spanish Ministerio de Economía y Competitividad (BES-2016-076298). JP-G was supported by the FPU program from the Spanish Ministerio de Educación, Cultura y Deporte (FPU16/01573) SI

Previous research has shown that feedback evaluation is sensitive to monetary incentive. We investigated whether this sensitivity is driven by motivational salience (the difference between both rewarding and punishing events versus neutral events) or by motivational valence (the difference between rewarding and punishing events). Fifty-seven participants performed a monetary incentive delay task under a gain context, a loss context, and a neutral context with their electroencephalogram recorded. During the time domain, the feedback-related negativity (FRN) showed a motivational salience effect whereas the P3 displayed a reward valence effect. During the time-frequency domain, we observed a motivational salience effect for phase-locked theta power regardless of performance feedback, but a reward valence effect for non-phase-locked theta power in response to unsuccessful feedback. Moreover, we found a reward valence effect for phase-locked delta. These findings thus suggest that the affective modulation on feedback evaluation can be driven either by motivational valence or by motivational salience, which depends on the temporal dynamics (the FRN vs. the P3), the frequency dynamics (theta vs. delta power), as well as the phase dynamics (evoked vs. induced power).

Cues predicting rewards can gain motivational properties and initiate reward-seeking behaviors. Dopamine projections from the ventral tegmental area (VTA) to the nucleus accumbens (NAc) are critical in regulating cue-motivated responding. Although, approximately one third of mesoaccumbal projection neurons are GABAergic, it is unclear how this population influences motivational processes and cue processing. This is largely due to our inability to pharmacologically probe circuit level contributions of VTA-GABA, which arises from diverse sources, including multiple GABA afferents, interneurons, and projection neurons. Here we used a combinatorial viral vector approach to restrict activating Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) to GABA neurons in the VTA of wild-type rats trained to respond during a distinct audiovisual cue for sucrose. We measured different aspects of motivation for the cue or primary reinforcer, while chemogenetically activating either the VTA-GABA neurons or their projections to the NAc. Activation of VTA-GABA neurons decreased cue-induced responding and accuracy, while increasing latencies to respond to the cue and obtain the reward. Perseverative and spontaneous responses decreased, yet the rats persisted in entering the reward cup when the cue and reward were absent. However, activation of the VTA-GABA terminals in the accumbens had no effect on any of these behaviors. Together, we demonstrate that VTA-GABA neuron activity preferentially attenuates the ability of cues to trigger reward-seeking, while some aspects of the motivation for the reward itself are preserved. Additionally, the dense VTA-GABA projections to the NAc do not influence the motivational salience of the cue.

The aim of the study was to investigate the efficiency of the use of response-contingent feedback in adolescents with and without developmental language disorder (DLD) by using the balloon analogue risk task (BART). The BIS/BAS scales were also used to evaluate a participant's responses to reward- or punishment-related events in everyday situations. The results showed that adolescents with DLD performed on the BART at a suboptimal level due to inefficient use of response-contingent feedback. Findings of the BIS/BAS scales also generate a possible hypothesis of reduced motivational salience for larger monetary outcomes in DLD. Given that dopamine plays an important role in modulating BART responding through the corticostriatal pathways, these behavioral findings implicate an association between dopamine and individual differences in language, including DLD. Future studies are needed to directly test whether people with DLD have reduced level of dopamine in striatal neural synapses, leading to dopamine-dependent learning difficulty.

Facial expressions of emotion have an undeniable processing advantage over neutral faces, discernible both at behavioral level and in emotion-related modulations of several event-related potentials (ERPs). Recently it was proposed that also inherently neutral stimuli might gain salience through associative learning mechanisms. The present study investigated whether acquired motivational salience leads to processing advantages similar to biologically determined origins of inherent emotional salience by applying an associative learning paradigm to human face processing. Participants (N=24) were trained to categorize neutral faces to salience categories by receiving different monetary outcomes. ERPs were recorded in a subsequent test phase consisting of gender decisions on previously associated faces, as well as on familiarized and novel faces expressing happy, angry or no emotion. Previously reward-associated faces boosted the P1 component, indicating that acquired reward-associations modulate early sensory processing in extrastriate visual cortex. However, ERP modulations to emotional - primarily angry - expressions expanded to subsequent processing stages, as reflected in well-established emotion-related ERPs. The present study offers new evidence that motivational salience associated to inherently neutral stimuli can sharpen sensory encoding but does not obligatorily lead to preferential processing at later stages.

Motivationally relevant stimuli benefit from strengthened sensory processing. It is unclear, however, if motivational value of positive and negative valence has similar or dissociable effects on early visual processing. Moreover, whether these perceptual effects are task-specific, stimulus-specific, or more generally feature-based is unknown. In this study, we compared the effects of positive and negative motivational value on early sensory processing using ERPs. We tested the extent to which these effects could generalize to new task contexts and to stimuli sharing common features with the motivationally significant ones. At the behavioral level, stimuli paired with positive incentives were learned faster than stimuli paired with neutral or negative outcomes. The ERP results showed that monetary loss elicited higher neural activity in V1 (at the C1 level) compared with reward, whereas the latter influenced postperceptual processing stages (P300). Importantly, the early loss-related effect generalized to new contexts and to new stimuli with common features, whereas the later reward effects did not spill over to the new context. These results suggest that acquired negative motivational salience can influence early sensory processing by means of plastic changes in feature-based processing in V1.

Author(s): Guillot, Casey R; Halliday, Teresa M; Kirkpatrick, Matthew G; Pang, Raina D; Leventhal, Adam M | Abstract: IntroductionAnhedonia-diminished interest or pleasure in response to rewards-is a dimension implicated in several psychiatric disorders linked to smoking. This laboratory study sought to identify motivational mechanisms linking anhedonia and tobacco addiction by testing the hypothesis that anhedonia, abstinence, and their interaction would predict excesses and deficits in the perceived pleasantness of smoking-related and positive pictures, respectively. We assessed the pleasantness of negative pictures as a secondary outcome.MethodsAfter a baseline session involving self-report measures of anhedonia and other factors, 125 regular smokers attended two counterbalanced experimental sessions (overnight abstinent and non-abstinent) at which they rated the pleasantness of positive, smoking-related, negative, and neutral (control) pictures presented via computer. The difference in pleasantness ratings of positive, smoking-related, and negative pictures relative to neutral pictures served as the index of participants' appraisal of the motivational salience of nondrug reward, drug reward, and aversive signals, respectively.ResultsWith and without adjusting for sex and depressive symptoms, greater anhedonia significantly or marginally predicted greater pleasantness of smoking (vs. neutral), lower pleasantness of positive (vs. neutral), less unpleasantness of negative (vs. neutral) pictures (|βs| = 0.18 to 0.35, ps = .007 to .07). Anhedonia by abstinence interaction effects on pleasantness ratings of each stimulus category (vs. neutral) were not significant (|βs| ≤ 0.02, ps ≥ .36).ConclusionsAnhedonia and abstinence additively increase the salience of smoking-related cues in anhedonic smokers. Smoking cessation efforts that attenuate sensitization to smoking stimuli may benefit anhedonic smokers early in quit attempts.ImplicationsTaken together, these findings provide tentative evidence that anhedonia is associated with a relative imbalance in the motivational salience of drug relative to nondrug rewards and may be associated with a generalized hypo-reactivity to both positive and negative stimuli. Though some prior smoking research has evidenced this relative imbalance in anhedonia with self-report or a smoking-choice task, we additionally show that this pattern may extend to hyper-affective reactivity to smoking-related stimuli being coincident with hypo-affective reactivity to nondrug-related positive stimuli (ie, may extend to greater pleasantness ratings of smoking pictures being accompanied by lower pleasantness ratings of positive pictures).

The development of drug addiction is associated with functional adaptations within the reward circuitry, within which the nucleus accumbens (NAc) is anatomically positioned as an interface between motivational salience and behavioral output. The functional output of NAc is profoundly altered after exposure to drugs of abuse, and some of the functional changes continue to evolve during drug abstinence, contributing to numerous emotional and motivational alterations related drug taking, seeking, and relapse. As in most brain regions, the functional output of NAc is critically dependent on the dynamic interaction between excitation and inhibition. One of the most prominent sources of inhibition within the NAc arises from fast-spiking interneurons (FSIs). Each NAc FSI innervates hundreds of principal neurons, and orchestrates population activity through its powerful and sustained feedforward inhibition. While the role of NAc FSIs in the context of drug addiction remains poorly understood, emerging evidence suggests that FSIs and FSI-mediated local circuits are key targets for drugs of abuse to tilt the functional output of NAc toward a motivational state favoring drug seeking and relapse. In this review, we discuss recent findings and our conceptualization about NAc FSI-mediated regulation of motivated and cocaine-induced behaviors. We hope that the conceptual framework proposed in this review may provide a useful guidance for ongoing and future studies to determine how FSIs influence the function of NAc and related reward circuits, ultimately leading to addictive behaviors.

There is sufficient evidence to believe that variations in the error-related negativity (ERN) are linked to dispositional characteristics in individuals. However, explanations of individual differences in the amplitude of the ERN cannot be derived from functional theories of the ERN. The ERN has a counterpart that occurs after correct responses (correct-response negativity, CRN). Based on the assumption that ERN and CRN reflect an identical cognitive process, variations in CRN might be associated with dispositional characteristics as well. Higher CRN amplitudes have been found to reflect task engagement. In the present study, a simple-choice-reaction task was used to investigate ERN and CRN amplitudes in relation to their score on a conscientiousness scale. The task consisted of a simple rule that required pressing the left or right key when a circle or square appeared, respectively. During alternative conditions that occur infrequently, participants were instructed to violate or reverse the previously established response rules. Smaller ΔERN amplitudes (manifested in almost equal CRN and ERN amplitudes) and a tendency of better task performance from participants scoring high on the conscientiousness scale might indicate a greater focus on the task and higher motivation of responding correctly. In addition, higher Pc amplitudes directly following the CRN indicated that the response monitoring system of less conscientious participants showed a higher disengagement. The role of individual differences in CRN amplitude should be studied in future experiments on performance monitoring.

Emotionally arousing cues automatically attract attentional resources, which may be at the cost of processing task-related information. Of central importance is how the visual system resolves competition for processing resources among stimuli differing in motivational salience. Here, we assessed the extent and time-course of competition between emotionally arousing distractors and task-related stimuli in a frequency-tagging paradigm. Steady-state visual evoked potentials (ssVEPs) were evoked using random-dot kinematograms that consisted of rapidly flickering (8.57 Hz) dots, superimposed upon emotional or neutral distractor pictures flickering at 12 Hz. The time-varying amplitude of the ssVEP evoked by the motion detection task showed a significant reduction to the task-relevant stream while emotionally arousing pictures were presented as distractors. Competition between emotionally arousing pictures and moving dots began 450 ms after picture onset and persisted for an additional 2600 ms. Competitive effects of the overlapping task and picture stream revealed cost effects for the motion detection task when unpleasant pictures were presented as distractors between 450 and 1650 ms after picture onset, where an increase in ssVEP amplitude to the flickering picture stimulus was at the cost of ssVEP amplitude to the flickering dot stimulus. Cost effects were generalized to all emotionally arousing contents between 1850 and 3050 ms after picture onset, where the greatest amount of competition was evident for conditions in which emotionally arousing pictures, compared to neutral, served as distractors. In sum, the processing capacity of the visual system as measured by ssVEPs is limited, resulting in prioritized processing of emotionally relevant cues.

Bipolar spectrum and unipolar depressive disorders have been associated with distinct and opposite profiles of reward-related neural activity. These opposite profiles may reflect a differential preexisting vulnerability for both types of disorders. In support, recent ERP studies find that, following reward feedback, a larger reward positivity (RewP) is associated with greater vulnerability for bipolar spectrum disorders, whereas a smaller RewP is associated with greater vulnerability for depression. However, prior studies have investigated only immediate rewards and have not examined dimensions of both bipolar disorder and unipolar depression within the same sample. The present study is the first to investigate feedback-related ERP correlates of proneness to hypomania and unipolar depressive tendencies within the same sample and to expand our scope to include future rewards. Participants completed a modified time estimation task where the same monetary reward was available immediately or at one of five different future dates. Results revealed proneness to hypomania and unipolar depressive tendencies were related to an elevated and blunted RewP, respectively, but only following immediate rewards (i.e., today). Following rewards in the distant future (e.g., 8 months), proneness to hypomania and depressive tendencies were associated with elevated and blunted amplitudes for the P3, respectively, a subsequent ERP component reflecting motivational salience during extended feedback processing. Furthermore, these opposing profiles were independent of, and significantly different from, one another. These results suggest that feedback-related ERPs following immediate and future rewards are candidate biomarkers that can physiologically separate vulnerability for bipolar spectrum from unipolar depressive disorders.

It has been shown that when incentives are provided during movement preparation, activity in parieto-frontal regions reflects both expected value and motivational salience. Yet behavioral work suggests that the processing of rewards is faster than for punishments, raising the possibility that expected value and motivational salience manifest at different latencies during movement planning. Given the role of beta oscillations (13–30 Hz) in movement preparation and in communication within the reward circuit, this study investigated how beta activity is modulated by positive and negative monetary incentives during reach planning, and in particular whether it reflects expected value and motivational salience at different latencies. Electroencephalography was recorded while male and female humans performed a reaching task in which reward or punishment delivery depended on movement accuracy. Before a preparatory delay period, participants were informed of the consequences of hitting or missing the target, according to four experimental conditions: Neutral (hit/miss:+0/−0¢), Reward (hit/miss:+5/−0¢), Punish (hit/miss:+0/−5¢) and Mixed (hit/miss:+5/−5¢). Results revealed that beta power over parieto-frontal regions was strongly modulated by incentives during the delay period, with power positively correlating with movement times. Interestingly, beta power was selectively sensitive to potential rewards early in the delay period, after which it came to reflect motivational salience as movement onset neared. These results demonstrate that beta activity reflects expected value and motivational salience on different time scales during reach planning. They also provide support for models that link beta activity with basal ganglia and dopamine for the allocation of neural resources according to behavioral salience.SIGNIFICANCE STATEMENTThe present work demonstrates that pre-movement parieto-frontal beta power is modulated by monetary incentives in a goal-directed reaching task. Specifically, beta power transiently scaled with the availability of rewards early in movement planning, before reflecting motivational salience as movement onset neared. Moreover, pre-movement beta activity correlated with the vigor of the upcoming movement. These findings suggest that beta oscillations reflect neural processes that mediate the invigorating effect of incentives on motor performance, possibly through dopamine-mediated interactions with the basal ganglia.

It is widely believed that females outperformed males in emotional information processing. The present study tested whether the female superiority in emotional information processing exists in a naturalistic social-emotional context, if so, what the temporal dynamics underlies. The behavioral and electrophysiological responses were recorded while participants were performing an interpersonal gambling game with opponents’ facial emotions given as feedback. The results yielded that emotional cues modulated the influence of monetary feedback on outcome valuation. Critically, this modulation was more conspicuous in females: opponents’ angry expressions increased females’ risky tendency and decreased the amplitude of reward positivity (RewP) and feedback P300. These findings indicate that females are more sensitive to emotional expressions in real interpersonal interactions, which is manifested in both early motivational salience detection and late conscious cognitive appraisal stages of feedback processing.