ERPs associated with monitoring and evaluation of monetary reward and punishment in children with ADHD.

BACKGROUND: Several models of attention-deficit hyperactivity disorder (ADHD) propose abnormalities in the response to behavioural contingencies. Using event-related potentials (ERPs), the present study investigated the monitoring and subsequent evaluation of performance feedback resulting in either reward or punishment in children with ADHD (N = 18) and normal controls (N = 18) aged 8 to 12 years. METHODS: Children performed a time production task, in which visual performance feedback was given after each response. To manipulate its motivational salience, feedback was coupled with monetary gains, losses or no incentives. RESULTS: Performance feedback signalling omitted gains as well as omitted losses evoked a feedback-related negativity (FRN) in control children. The FRN, however, was entirely absent in children with ADHD in all conditions. Moreover, while losses elicited enhanced amplitudes of the late positive potential (LPP) in controls, omitted rewards had this effect in ADHD. CONCLUSIONS: The lack of modulation of the FRN by contingencies in ADHD suggests deficient detection of environmental cues as a function of their motivational significance. LPP findings suggest diminished response to punishment, but oversensitivity to the loss of desired rewards. These findings suggest that children with ADHD have problems assigning relative motivational significance to outcomes of their actions.

What motivates the adolescent? Brain regions mediating reward sensitivity across adolescence.

The relation between brain development across adolescence and adolescent risky behavior has attracted increasing interest in recent years. It has been proposed that adolescents are hypersensitive to reward because of an imbalance in the developmental pattern followed by the striatum and prefrontal cortex. To date, it is unclear if adolescents engage in risky behavior because they overestimate potential rewards or respond more to received rewards and whether these effects occur in the absence of decisions. In this study, we used a functional magnetic resonance imaging paradigm that allowed us to dissociate effects of the anticipation, receipt, and omission of reward in 10- to 12-year-old, 14- to 15-year-old, and 18- to 23-year-old participants. We show that in anticipation of uncertain outcomes, the anterior insula is more active in adolescents compared with young adults and that the ventral striatum shows a reward-related peak in middle adolescence, whereas young adults show orbitofrontal cortex activation to omitted reward. These regions show distinct developmental trajectories. This study supports the hypothesis that adolescents are hypersensitive to reward and adds to the current literature in demonstrating that neural activation differs in adolescents even for small rewards in the absence of choice. These findings may have important implications for understanding adolescent risk-taking behavior.

Does reward frequency or magnitude drive reinforcement-learning in attention-deficit/hyperactivity disorder?

Children with attention-deficit/hyperactivity disorder (ADHD) show an impaired ability to use feedback in the context of learning. A stimulus-response learning task was used to investigate whether (1) children with ADHD displayed flatter learning curves, (2) reinforcement-learning in ADHD was sensitive to either reward frequency, magnitude, or both, and (3) altered sensitivity to reward was specific to ADHD or would co-occur in a group of children with autism spectrum disorder (ASD). Performance of 23 boys with ADHD was compared with that of 30 normal controls (NCs) and 21 boys with ASD, all aged 8-12. Rewards were delivered contingent on performance and varied both in frequency (low, high) and magnitude (small, large). The findings showed that, although learning rates were comparable across groups, both clinical groups committed more errors than NCs. In contrast to the NC boys, boys with ADHD were unaffected by frequency and magnitude of reward. The NC group and, to some extent, the ASD group showed improved performance, when rewards were delivered infrequently versus frequently. Children with ADHD as well as children with ASD displayed difficulties in stimulus-response coupling that were independent of motivational modulations. Possibly, these deficits are related to abnormal reinforcement expectancy.

What's in a game: the effect of social motivation on interference control in boys with ADHD and autism spectrum disorders.

BACKGROUND: Children with attention deficit hyperactivity disorder (ADHD) and with autism spectrum disorders (ASD) are known to have cognitive control deficits. Some studies suggest that such deficits may be reduced when motivation is increased through tangible reinforcers. Whether these deficits can also be modulated by non-tangible reinforcers has hardly been studied. METHODS: Therefore, the effect of social motivation on the ability to suppress irrelevant information (i.e., interference control) was investigated in 22 ADHD boys, 22 ASD boys, and 33 typically developing (TD) boys. An adapted Eriksen Flanker task was administered under a motivational condition in which the boys were told that they were competing with peers, and under a neutral condition in which standard instructions were given. RESULTS: In comparison with TD boys, boys with ADHD were impaired even when no interference was present, while this was not the case for the ASD boys. All groups benefited from the motivation manipulation, i.e., their performance increased when they thought they were competing with peers. Although the boys with ADHD were still slower than TD boys when motivated, they performed as accurately as TD boys. Children with ASD also improved slightly in accuracy and response speed, but this did not reach significance. CONCLUSION: Children with ADHD are able to exert sufficient cognitive control when they are motivated, which is in line with the current models of ADHD. However, motivation seems to have a general effect on performance and is not solely related to cognitive control abilities. In contrast, this effect was not obtained in children with ASD.

Adaptive control deficits in attention-deficit/hyperactivity disorder (ADHD): the role of error processing.

Cognitive performance of children with attention-deficit hyperactivity disorder (ADHD) is characterized by large moment-to-moment fluctuations in cognitive control reflected by a highly inconsistent and inaccurate response style. It has been suggested that abnormal error processing underlies this failure to implement adequate control. We investigated the error-related negativity (ERN), a negative deflection in the event-related potential (ERP) time-locked to erroneous responses in 16 rigorously screened ADHD boys aged 8-12 years and 16 age-matched normal control boys during a modified Eriksen flanker paradigm with two levels of time pressure. Children with ADHD responded as fast and regularly as controls, but committed significantly more errors, particularly when facing time pressure and response conflict. ADHD children produced shorter runs of correct responses than controls. In addition, with high time pressure, error runs were prolonged relative to control children, suggesting an increase in both frequency and magnitude of temporary lapses of control. ERP amplitude differences between correct and incorrect responses were diminished in ADHD children, whereas post-error slowing remained unaffected. This pattern of results indicates that a specific deficit in monitoring ongoing behaviour, rather than insufficient strategic adjustments, gave rise to performance limitations in ADHD. Findings are discussed in terms of anterior cingulate cortex (ACC) dysfunction, leading to a failure to predict the likelihood that an error occurs in a given context.

Telling good from bad news: ADHD differentially affects processing of positive and negative feedback during guessing.

Neuroimaging studies on ADHD suggest abnormalities in brain regions associated with decision-making and reward processing such as the anterior cingulate cortex (ACC) and orbitofrontal cortex. Recently, event-related potential (ERP) studies demonstrated that the ACC is involved in processing feedback signals during guessing and gambling. The resulting negative deflection, the 'feedback-related negativity' (FRN) has been interpreted as reflecting an error in reward prediction. In the present study, ERPs elicited by positive and negative feedback were recorded in children with ADHD and normal controls during guessing. 'Correct' and 'incorrect' guesses resulted in respectively monetary gains and losses. The FRN amplitude to losses was more pronounced in the ADHD group than in normal controls. Positive and negative feedback differentially affected long latency components in the ERP waveforms of normal controls, but not ADHD children. These later deflections might be related to further emotional or strategic processing. The present findings suggest an enhanced sensitivity to unfavourable outcomes in children with ADHD, probably due to abnormalities in mesolimbic reward circuits. In addition, further processing, such as affective evaluation and the assessment of future consequences of the feedback signal seems to be altered in ADHD. These results may further help understanding the neural basis of decision-making deficits in ADHD.

Motivational effects on motor timing in attention-deficit/hyperactivity disorder.

OBJECTIVE: This study was designed to clarify whether poor performance of children with attention-deficit/hyperactivity disorder (ADHD) on motor timing tasks reflects a true deficit in the temporal organization of motor output or is due to a lack of intrinsic motivation. METHOD: Eighteen children with ADHD (age 8-12) were compared with 18 age- and gender-matched normal controls with respect to timing precision, timing variability, and the frequency of extreme under- and overestimations during a 1-second interval production task. Monetary reward, response cost, and no reward were implemented to manipulate motivation. RESULTS: Children with ADHD produced significantly more inaccurate and more variable time intervals and exhibited a larger number of extreme over- and underestimations than control children. Although all children performed significantly better when monetary incentives were applied, group differences were not eliminated. CONCLUSIONS: In this study, no evidence was found for a motivational deficit as an explanation for impaired performance on a time production task in ADHD. Rather, results provide clear support for a generic motor timing deficit, probably due to a dysfunctional frontostriatocerebellar network involved in temporal aspects of motor preparation.

Reward and punishment sensitivity in children with ADHD: validating the Sensitivity to Punishment and Sensitivity to Reward Questionnaire for children (SPSRQ-C).

This study validates the Sensitivity to Punishment and Sensitivity to Reward Questionnaire for children (SPSRQ-C), using a Dutch sample of 1234 children between 6-13 years old. Factor analysis determined that a 4-factor and a 5-factor solution were best fitting, explaining 41% and 50% of the variance respectively. The 4-factor model was highly similar to the original SPSRQ factors found in adults (Punishment Sensitivity, Reward Responsivity, Impulsivity/Fun-Seeking, and Drive). The 5-factor model was similar to the 4-factor model, with the exception of a subdivision of the Punishment Sensitivity factor into a factor with 'social-fear' items and a factor with 'anxiety' items. To determine external validity, scores of three groups of children with attention deficit hyperactivity disorder (ADHD) were compared on the EFA models: ADHD-only (n = 34), ADHD and autism spectrum disorder (ADHD+ASD; n = 22), ADHD and oppositional defiant disorder (ADHD+ODD; n = 22). All ADHD groups scored higher than typical controls on Reward Responsivity and on the 'anxiety' factor (n = 75). The ADHD-only and ADHD+ODD group scored higher than other groups on Impulsivity/Fun-Seeking and Drive, while the ADHD+ASD group scored higher on Punishment Sensitivity. The findings emphasize the value of the SPSRQ-C to quickly and reliably assess a child's sensitivity to reinforcement, with the aim to provide individually-tailored behavioral interventions that utilize reward and reprimands.

Developmental trajectories of neural mechanisms supporting conflict and error processing in middle childhood.

To study age-related changes in cognitive control, event-related potentials (ERPs) of children aged 6-9 years, 10-12 years, and young adults were recorded during a Flanker task. Younger children were more susceptible to conflict than older ones and adults. The N2 in incongruent trials was smaller in younger than older children, who did not differ from adults. The error-related negativity (ERN) following errors, however, was larger in adults than in children, but did not differ between younger and older children. Delayed development of neural responses to error processing relative to conflict monitoring may indicate dissociable maturational time tables of subdivisions of the anterior cingulate cortex.

Diminished error processing in smokers during smoking cue exposure.

Deficits in error processing may contribute to the continuation of impulsive behaviors such as smoking. Previous studies show deficits in error processing among substance abuse patients. However, these studies were all conducted during affectively neutral conditions. Deficits in error processing in smokers may become more pronounced under affectively challenging conditions, such as during smoking cue exposure. The aim of the present study was to investigate whether smokers showed initial error processing deficits, as measured with the error-related negativity (ERN), and decreased motivational significance attributed to an error, as measured with the error positivity (Pe) when exposed to smoking cues. Additionally, we examined the nature of the ERN and Pe amplitudes in more detail by investigating their associations with trait impulsivity, nicotine dependence levels and cigarette craving. Event-related potentials were measured during a modified Erikson flanker task in both smokers and non-smoking controls. Smokers showed reduced ERN and Pe amplitudes after making an error, accompanied by diminished post-error slowing of reaction times. These results suggest that initial error processing and motivational significance attributed to an error are affected in smokers during smoking cue exposure. Furthermore, individual variation in impulsivity and nicotine dependence was associated with reduced ERN amplitudes.

Acute effects of alcohol on feedback processing and outcome evaluation during risky decision-making: an ERP study.

RATIONALE: Although risky decision-making is one of the hallmarks of alcohol use disorders, relatively little is known about the acute psychopharmacological effects of alcohol on decision-making processes. OBJECTIVE: The present study investigated the acute effects of alcohol on neural mechanisms underlying feedback processing and outcome evaluation during risky decision-making, using event-related brain potentials (ERPs). METHODS: ERPs elicited by positive and negative feedback were recorded during performance of a modified version of the Balloon Analogue Risk Task in male participants receiving either a moderate dose of alcohol (0.65 g/kg alcohol; n = 32) or a non-alcoholic placebo beverage (n = 32). RESULTS: Overall, there was no significant difference in the mean number of pumps between the alcohol and the placebo condition. However, when analyzing over time, it was found that the alcohol group made more riskier choices at the beginning of the task than the placebo group. ERPs demonstrated that alcohol consumption did not affect early processing of negative feedback, indexed by the feedback-related negativity. By contrast, alcohol-intoxicated individuals showed significantly reduced P300 amplitudes in response to negative feedback as compared to sober controls, suggesting that more elaborate evaluation to losses was significantly diminished. CONCLUSIONS: These results suggest that alcohol consumption does not influence the ability to rapidly evaluate feedback valence, but rather the ability to assign sufficient attention to further process motivationally salient outcomes. Blunted P300 amplitudes may reflect poor integration of feedback across trials, particularly adverse ones. Consequently, alcohol may keep people from effectively predicting the probability of future gains and losses based on their reinforcement history.

The effect of interpersonal competition on monitoring internal and external error feedback.

Abstract The present study examined the effect of the social context on early emotional appraisal of performance errors and negative feedback reflected by the error-related negativity (ERN), feedback-related negativity (FRN), and P300. Participants performed a probabilistic learning task in which they received valid and invalid performance feedback. During one half of the task they were led to believe that they were competing online against another participant. As expected, the ERN following response errors was enhanced in the competition compared to the neutral condition. The FRN was more negative following negative compared to positive feedback and valid compared to invalid feedback, but only during competition. The P300 was larger to false positive than false negative feedback, which was independent of the social context. In conclusion, ERN and FRN, but not P300, may be sensitive to affective distress elicited by expectation violations during social interaction.

Heart rate and reinforcement sensitivity in ADHD.

BACKGROUND: Both theoretical and clinical accounts of attention-deficit/hyperactivity disorder (ADHD) implicate a dysfunctional reinforcement system. This study investigated heart rate parameters in response to feedback associated with reward and response cost in ADHD children and controls aged 8 to 12. METHODS: Heart rate responses (HRRs) following feedback and heart rate variability (HRV) in the low frequency band (.04-.08 Hz), a measure of mental effort, were calculated during a time production paradigm. Performance was coupled to monetary gain, loss or feedback-only in a cross-over design. RESULTS: Children with ADHD exhibited smaller HRRs to feedback compared to controls. HRV of children with ADHD decreased when performance was coupled to reward or response cost compared to feedback-only. HRV of controls was similar across conditions. CONCLUSIONS: Children with ADHD were characterised by (a) possible abnormalities in feedback monitoring and (b) motivational deficits, when no external reinforcement is present.