金钱奖赏对海洛因戒断者工作记忆刷新功能的促进作用减弱

采用有无金钱奖赏条件下的n-back任务，探讨金钱奖赏对海洛因戒断者工作记忆刷新功能的影响。结果发现：所有被试在金钱奖赏条件下的反应时都显著短于无奖赏条件下的反应时；海洛因戒断组在有无金钱奖赏条件下的反应时的差值显著小于正常组在有无金钱奖赏条件下的反应时的差值；在1-back和2-back任务中，正常组的正确率显著高于海洛因戒断组的正确率。结果表明：金钱奖赏对海洛因戒断者工作记忆刷新功能存在一定的促进作用，但是其促进作用幅度要弱于正常人；海洛因戒断者的工作记忆刷新功能可能存在损伤。     

Differential effects of social and non‐social reward on response inhibition in children and adolescents

An important issue in the field of clinical and developmental psychopathology is whether cognitive control processes, such as response inhibition, can be specifically enhanced by motivation. To determine whether non‐social (i.e. monetary) and social (i.e. positive facial expressions) rewards are able to differentially improve response inhibition accuracy in typically developing children and adolescents, an ‘incentive’ go/no‐go task was applied with reward contingencies for successful inhibition. In addition, the impact of children's personality traits (such as reward seeking and empathy) on monetary and social reward responsiveness was assessed in 65 boys, ages 8 to 12 years. All subjects were tested twice: At baseline, inhibitory control was assessed without reward, and then subjects were pseudorandomly assigned to one of four experimental conditions, including (1) social reward only, (2) monetary reward only, (3) mixed social and monetary reward, or (4) a retest condition without reward. Both social and non‐social reward significantly improved task performance, although larger effects were observed for monetary reward. The higher the children scored on reward seeking scales, the larger was their improvement in response inhibition, but only if monetary reward was used. In addition, there was a tendency for an association between empathic skills and benefits from social reward. These data suggest that social incentives do not have an equally strong reinforcing value as compared to financial incentives. However, different personality traits seem to determine to what extent a child profits from different types of reward. Clinical implications regarding probable hyposensitivity to social reward in subjects with autism and dysregulated reward‐seeking behaviour in children with attention‐deficit/hyperactivity disorder (ADHD) are discussed.     

Monetary reward increases attentional effort in the flanker task

An important question is whether monetary reward can increase attentional effort in order to improve performance. Up to now, evidence for a positive answer is weak. Therefore, in the present study, the flanker task was used to examine this question further. Participants had to respond sooner than a certain deadline in a flanker task. One group of participants received a performance-contingent monetary reward, whereas the other group earned a fixed amount of money. As a result, monetary reward significantly improved performance in comparison with the control group. The analysis of speed-accuracy trade-off functions revealed that monetary reward increased attentional effort, leading to an enhanced quality of stimulus coding. Little evidence was found that reward also improved selective spatial attention.     

Integrating rewards and cognition in the frontal cortex

Research indicates that the dorsolateral prefrontal cortex (DLPFC) contributes to working memory and executive control, whereas the ventral frontal cortex (VFC) contributes to affective and motivational processing. Few studies have examined both the functional specificity and the integration of these regions. We did so using fMRI and a verbal working memory task in which visual cues indicated whether recall performance on an upcoming trial would be linked to a monetary reward. On the basis of prior findings obtained in delayed response tasks performed by nonhuman primates, we hypothesized that (1) VFC would show an increase only in response to a cue indicating potential for a monetary reward; (2) DLPFC would show sustained activity across a delay interval for all trials, though activity in rewarded trials would be enhanced; and (3) regions engaged in speech-based rehearsal would be relatively insensitive to monetary incentive. Our hypotheses about DLPFC and rehearsal-related regions were confirmed. In VFC regions, we failed to observe statistically significant effects of reward when the cue or delay epochs of the task were examined in isolation. However, an unexpected and significant deactivation was observed in VFC during the delay epoch; furthermore, a post hoc voxelwise analysis indicated a complex interaction between (1) the cue and delay epochs of the task and (2) the reward value of the trials. The pattern of activation and deactivation across trial types suggests that VFC is sensitive to reward cues, and that portions of DLPFC and VFC may work in opposition during the delay epoch of a working memory task in order to facilitate task performance.     

Task Incentives,Type A Behavior Pattern,and Verbal Problem Solving Performance1

A laboratory experiment was conducted to investigate the interaction between task incentives and the Type A behavior pattern in determining performance during a task of verbal problem solving. The results indicated that Type A subjects responded more quickly and more frequently than their Type B counterparts. In addition, evidence suggested that a situational characteristic–whether instructions offered a monetary reward or served as an evaluative stressor–affected subjects differently depending on their behavior pattern classification. These findings suggest that Pattern A behavior occurs as a response to challenges signifying the potential for reward as well as a threat of failure. Implications for future research emphasize the need to investigate the characteristics of the situation and the task, as well as the individual.     

Reward priming of temporal preparation

Recent studies have demonstrated a strong impact of reward on the expectancy of future target locations or features. In this study, we examined whether reward would have similar effects on temporal preparation. In two experiments, participants completed a reaction time task with a variable interval between a warning stimulus and the target stimulus. After each trial they were awarded either low or high reward which was converted to cash after the experiment. Crucially, reward magnitude was assigned randomly and was unrelated to task performance. Nevertheless, across experiments, the results revealed that reward modified future temporal preparation, especially in participants that could be identified as highly motivated. These findings generalize the principles of reward priming to the temporal domain.     

Utilization of reward-prospect enhances preparatory attention and reduces stimulus conflict

The prospect of gaining money is an incentive widely at play in the real world. Such monetary motivation might have particularly strong influence when the cognitive system is challenged, such as when needing to process conflicting stimulus inputs. Here, we employed manipulations of reward-prospect and attentional-preparation levels in a cued-Stroop stimulus conflict task, along with the high temporal resolution of electrical brain recordings, to provide insight into the mechanisms by which reward-prospect and attention interact and modulate cognitive task performance. In this task, the cue indicated whether or not the participant needed to prepare for an upcoming Stroop stimulus and, if so, whether there was the potential for monetary reward (dependent on performance on that trial). Both cued attention and cued reward-prospect enhanced preparatory neural activity, as reflected by increases in the hallmark attention-related negative-polarity ERP slow wave (contingent negative variation [CNV]) and reductions in oscillatory Alpha activity, which was followed by enhanced processing of the subsequent Stroop stimulus. In addition, similar modulations of preparatory neural activity (larger CNVs and reduced Alpha) predicted shorter versus longer response times (RTs) to the subsequent target stimulus, consistent with such modulations reflecting trial-to-trial variations in attention. Particularly striking were the individual differences in the utilization of reward-prospect information. In particular, the size of the reward effects on the preparatory neural activity correlated across participants with the degree to which reward-prospect both facilitated overall task performance (shorter RTs) and reduced conflict-related behavioral interference. Thus, the prospect of reward appears to recruit attentional preparation circuits to enhance processing of task-relevant target information.     

Cheating,intention, and punishment from an equity theory perspective

Male college students were given the opportunity to deliver aversive noise to a partner (confederate) contingent on the partner's “mistakes” in a learning task. Subjects were either not informed about a reward or told that they, their partner, or a charity would receive a monetary reward for speedy learning. Half of the subjects observed the confederate cheat, while half did not observe any deceptive behavior. The intensity of punitive behavior seemed to vary in accordance with predictions derived from equity theory. That is, cheating for a charity, a “good cause” resulted in less intense punishment than did cheating for selfish gain. On the other hand, mistakes, uncomplicated by cheating, which deprived a charity were punished more intensely than were mistakes whose only result accrued to the confederate himself.     

Self-reinforcement: Impact of instructions,criterion setting,and tangible rewards

This investigation was designed to ascertain the effects of instructions, criterion setting, and the presence of tangible rewards on the self-reinforcement process. Fifty-two third- and fourth-grade subjects were assigned to one of four treatment groups: (a) stringent instructions/criterion setting/tangible reward, (b) stringent instructions/criterion setting/no tangible reward, (c) nonstringent instructions/criterion setting/tangible reward, and (d) nonstringent instructions/no tangible reward. In the stringent-instruction conditions, subjects received social reinforcement for selecting stringent performance criteria, whereas in the non-stringent-instruction conditions, social reinforcement was withheld. Subjects in the tangible-reward groups were allowed to select a prize following the successful completion of their self-selected work performance. Subjects in the no-tangible-reward groups received no prizes for their work. All subjects performed an arithmetic task in which the number of correct problems completed, number of problems attempted, and time at task served as dependent variables across five reinforcement and two extinction trials. The results suggest that the condition of stringent instructions, criterion setting, and tangible reward was more effective in producing behavior change than the other three conditions. Perceived task difficulty and previous achievement on arithmetic task performance were shown to affect criteria selected and mathematical performance. The results are discussed in light of the contributory role of instructions, criterion setting, and tangible rewards on the self-reinforcement procedure.This study is based on a doctoral dissertation submitted to the Faculty of Arts and Sciences at the University of Pittsburgh by Helen L. Evans. Dr. Russell T. Jones was the dissertation committee chairperson. It was partially funded by an American Psychological Association Minority Fellowship awarded to the first author. Special thanks are extended to the committee members, Drs. Lloyd Bond, Robert Glaser, Johnny Matson, and Samuel M. Turner, for their assistance. The authors would like to thank Thomas DeVoge, Paul Karoly, and Samuel M. Turner for reading and commenting on an early draft of this study. Portions of this paper were presented at the 1982 APA convention.     

Age differences in the neural response to negative feedback

Affective processing is one domain that remains relatively intact in healthy aging. Investigations into the neural responses associated with reward anticipation have revealed that older and younger adults recruit the same midbrain reward regions, but other evidence suggests this recruitment may differ depending on the valence (gain, loss) of the incentive cue. The goal of the current study was to examine functional covariance during gain and loss feedback in younger and healthy older adults. A group of 15 older adults (mean age = 68.5) and 16 younger adults (mean age = 25.4) completed a revised Monetary Incentive Delay task (rMID; Knutson, Westdorp, Kaiser, &; Hommer, 2000) while in the fMRI scanner. The rMID is a reaction time task where successful performance, either gaining a reward or avoiding a loss, is defined by hitting a button during the brief presentation of a visual target. Participants receive gain and loss anticipation cues before each trial and feedback after each trial with four possible outcomes: +$5.00, +0.00, -$5.00, and -Affective processing is one domain that remains relatively intact in healthy aging. Investigations into the neural responses associated with reward anticipation have revealed that older and younger adults recruit the same midbrain reward regions, but other evidence suggests this recruitment may differ depending on the valence (gain, loss) of the incentive cue. The goal of the current study was to examine functional covariance during gain and loss feedback in younger and healthy older adults. A group of 15 older adults (mean age = 68.5) and 16 younger adults (mean age = 25.4) completed a revised Monetary Incentive Delay task (rMID; Knutson, Westdorp, Kaiser, & Hommer, 2000) while in the fMRI scanner. The rMID is a reaction time task where successful performance, either gaining a reward or avoiding a loss, is defined by hitting a button during the brief presentation of a visual target. Participants receive gain and loss anticipation cues before each trial and feedback after each trial with four possible outcomes: +$5.00, +0.00, -$5.00, and -$0.00. Using seed-voxel partial least squares analyses, with seed voxels in the caudate and ventromedial prefrontal cortex, whole-brain functional covariance revealed that younger and older adults engage the same network of regions to support general feedback processing. However, older adults engaged two additional networks to support processing of negative feedback, gain_miss (+0), loss_miss (-$5), and loss_hit (?0), specifically. These findings are in line with theories of a positivity effect in aging and may have implications for reward-stimulus learning and decision making following performance-contingent negative feedback.     

Cueing task goals and earning money: Relatively high monetary rewards reduce failures to act on goals in a Stroop task

We examined the role of monetary rewards in failures to act on goals in a Stroop task. Based on recent developments in theorizing on the interplay between rewards and cognitive control, we hypothesized that relatively high monetary rewards enhance the focus and stability of a cued task goal compared to low monetary rewards, and hence cause a reduction in failures to act on current task goals under circumstances that warrant top–down goal implementation. To test this, participants received a modified version of the Stroop task, in which they were either briefly cued with the goal of naming the color or meaning of targets on a trial-by-trial basis. After goal cuing, but before presenting the target, either a low or high reward cue was presented. Results showed that higher rewards produced a general speed-up. More importantly, Stroop interference on error rates was lower in the high reward condition compared to the low reward condition, revealing that the rewards enhanced focus and stability of the cued goal. These results provide support for theorizing that reward processing modulates utility assessment of current goals by affecting attention to facilitate goal-directed behavior.     

Rewarding performance feedback alters reported time of action

Past studies have shown that the perceived time of actions is retrospectively influenced by post-action events. The current study examined whether rewarding performance feedback (even when false) altered the reported time of action. In Experiment 1, participants performed a speeded button press task and received monetary reward for a presumed “fast,” or a monetary punishment for a presumed “slow” response. Rewarded trials resulted in the false perception that the response action occurred earlier than punished trials. In Experiments 2 and 3, the need for a speeded response and reward were independently manipulated in order to decouple the cognitive and reward components in the feedback signal. When tested independently, neither variable affected the judged time of action. We conclude that meaningful feedback (fast or slow) is only used when made salient by reward, to modulate the judged time of an action.     

Personality and the effects of stress on recognition memory

The experiment examined the contribution of anxiety, extraversion, neuroticism, and psychoticism to recognition memory for pictures and words using a signal detection method. Independent groups of subjects performed a recognition memory task under one of four conditions (control, noise, threat, and reward) that was intended to capitalize on dispositions which characterize the personality dimensions. In an ego threat condition involving personal evaluation, introverts displayed a performance decrement relative to noise and reward conditions. Psychoticism was inversely related to performance in the noise and threat conditions and directly related in a reward condition. In general, J. A. Gray's (1981) model of anxiety and impulsiveness accommodates much of the data, but the mechanisms which mediate the influence of personality on memory performance are not clear.     

Learning grammatical categories from distributional cues: Flexible frames for language acquisition

Performance in a behavioral task can be facilitated by associating stimulus properties with reward. In contrast, conflicting information is known to impede task performance. Here we investigated how reward associations influence the within-trial processing of conflicting information using a color-naming Stroop task in which a subset of ink colors (task-relevant dimension) was associated with monetary incentives. We found that color-naming performance was enhanced on trials with potential-reward versus those without. Moreover, in potential-reward trials, typical conflict-induced performance decrements were attenuated if the incongruent word (task-irrelevant dimension) was unrelated to reward. In contrast, incongruent words that were semantically related to reward-predicting ink colors interfered with performance in potential-reward trials and even more so in no-reward trials, despite the semantic meaning being entirely task-irrelevant. These observations imply that the prospect of reward enhances the processing of task-relevant stimulus information, whereas incongruent reward-related information in a task-irrelevant dimension can impede task performance.     

Undermining the Zeigarnik effect: Another hidden cost of reward

Forty college students participated in a study ostensibly designed to obtain measures of the hemispheric activity while they worked on a spatial reasoning task. In fact, our true interest was in determining whether subjects would return to the spatial reasoning task once the hemispheric recordings were completed. Subjects would normally be expected to return to the task by virtue of the Zeigarnik effect because no subject completed the task during the “hemispheric recording” phase. The manipulation involved telling one group of subjects that they would be paid $1.50 for participating in the study (expected reward group). The remainder of the subjects were not led to expect the reward (unexpected reward group). The result was that 86% of the unexpected reward subjects but only 58% of the expected reward subjects (p < .05) manifested the Zeigarnik effect. This differential tendency to return to the task was further reflected in time differences. The average unexpected reward subject spent 3 min 48 sec of a five-minute free-choice period at the task, whereas the average expected reward subject spent only 2 min 20 sec (p < .05). Reward expectancy, therefore, led to an undermining of the Zeigarnik effect. This observation supports Condry's prediction that rewarding performance at a task can lead to premature task disengagement.     

Tubes,tables and traps: great apes solve two functionally equivalent trap tasks but show no evidence of transfer across tasks

Previous studies on tool using have shown that presenting subjects with certain modifications in the experimental setup can substantially improve their performance. However, procedural modifications (e.g. trap table task) may not only remove task constraints but also simplify the problem conceptually. The goal of this study was to design a variation of the trap-table that was functionally equivalent to the trap-tube task. In this new task, the subjects had to decide where to insert the tool and in which direction the reward should be pushed. We also administered a trap-tube task that allowed animals to push or rake the reward with the tool to compare the subjects' performance on both tasks. We used a larger sample of subjects than in previous studies and from all the four species of great apes (Gorilla gorilla, Pan troglodytes, Pan paniscus, and Pongo pygmaeus). The results showed that apes performed better in the trap-platform task than in the trap-tube task. Subjects solved the tube task faster than in previous studies and they also preferred to rake in rather than to push the reward out. There was no correlation in the level of performance between both tasks, and no indication of interspecies differences. These data are consistent with the idea that apes may possess some specific causal knowledge of traps but may lack the ability to establish analogical relations between functional equivalent tasks.     

Fortune and reversals of fortune in visual search: Reward contingencies for pop-out targets affect search efficiency and target repetition effects

Rewards have long been known to modulate overt behavior. But their possible impact on attentional and perceptual processes is less well documented. Here, we study whether the (changeable) reward level associated with two different pop-out targets might affect visual search and trial-to-trial target repetition effects (see Maljkovic & Nakayama, 1994). Observers searched for a target diamond shape with a singleton color among distractor diamond shapes of another color (e.g., green among red or vice versa) and then judged whether the target had a notch at its top or bottom. Correct judgments led to reward, with symbolic feedback indicating this immediately; actual rewards accumulated for receipt at study end. One particular target color led to a higher (10:1) reward for 75% of its correct judgments, whereas the other singleton target color (counterbalanced over participants) yielded the higher reward on only 25% of the trials. We measured search performance in terms of inverse efficiency (response time/proportion correct). The reward schedules not only led to better performance overall for the more rewarding target color, but also increased trial-to-trial priming for successively repeated targets in that color. The actual level of reward received on the preceding trial affected this, as did (orthogonally) the likely level. When reward schedules were reversed within blocks, without explicit instruction, corresponding reversal of the impact on search performance emerged within around 6 trials, asymptoting at around 15 trials, apparently without the observers’ explicit knowledge of the contingency. These results establish that pop-out search and target repetition effects can be influenced by target reward levels, with search performance and repetition effects dynamically tracking changes in reward contingency.     

Unconscious reward facilitates motion perceptual learning

Reward signal plays an important role in guiding human learning behaviour. Recent studies have provided evidence that reward signal modulates perceptual learning of basic visual features. Typically, the reward effects on perceptual learning were accompanied with consciously presented reward during the learning process. However, whether an unconsciously presented reward signal that minimizes the contribution of attentional and motivational factors can facilitate perceptual learning remains less well understood. We trained human subjects on a visual motion detection task and subliminally delivered a monetary reward for correct response during the training. The results showed significantly larger learning effect for high reward-associated motion direction than low reward-associated motion direction. Importantly, subjects could neither discriminate the relative values of the subliminal monetary reward nor correctly report the reward-direction contingencies. Our findings suggest that reward signal plays an important modulatory role in perceptual learning even if the magnitude of the reward was not consciously perceived.     

Mood impact on cardiovascular reactivity when task difficulty is unclear

Research in the context of the mood-behavior-model (Gendolla in Rev Gen Psychol 4:348–408, 2000) has shown that moods can have an impact on effort mobilization due to congruency effects on demand appraisals. However, the mood research literature suggests that mood may also influence effort mobilization by its impact on appraisals of the instrumentality of success. In a single factor (mood valence: negative vs. neutral vs. positive) between-persons design, participants performed a memory task under conditions of unclear task difficulty. By successfully performing the task, participants could earn the chance to win a monetary reward. As predicted for tasks with unclear difficulty, effort mobilization—assessed as cardiovascular reactivity—increased from negative to positive mood. This effect was mediated by the subjective probability of winning the monetary reward for successful performance. These results demonstrate for the first time that mood can influence effort mobilization via the estimated instrumentality of success.     

What is pressure? Evidence for social pressure as a type of regulatory focus

Previous research (Markman, Maddox, & Worthy, 2006) suggests that pressure leads to choking when one is learning to classify items on the basis of an explicit rule, but it leads to excelling when one is learning to classify items on the basis of an implicit strategy. In this article, we relate social pressure to regulatory focus theory. We propose that the effects of pressure on performance arise because pressure induces a prevention focus that interacts with the more local reward structure of the task. To test this hypothesis, we repeated previous research, but using a losses reward structure, so that participants under pressure were in a regulatory fit. We also successfully replicated previous results by using a gains reward structure. In contrast with participants who attempted to maximize gains on each trial, participants who attempted to minimize losses choked on the implicit-learning task but excelled on the explicit-learning task. The results suggest a three-way interaction between pressure level, task type, and reward structure.