Determinants of reinforcer accumulation during an operant task.

Responses by rats on an earn lever made available food pellets that were delivered to a food cup by responses on a second, collect, lever. The rats could either collect and immediately consume or accumulate (defined as the percentage of multiple earn responses and as the number of pellets earned before a collect response) earned pellets. In Experiment 1, accumulation varied as a function of variations in the earn or collect response requirements and whether the earn and collect levers were proximal (31 cm) or distal (248 cm) to one another. Some accumulation occurred under all but one of the conditions, but generally was higher when the earn and collect levers were distal to one another, particularly when the earn response requirement was fixed-ratio (FR) 1. In Experiment 2, the contributions of responses and time to accumulation were assessed by comparing an FR 20 earn response requirement to a condition in which only a single earn response was required at the end of a time interval nominally yoked to the FR interval. When 248 cm separated the earn and collect levers, accumulation was always greater in the FR condition, and it was not systematically related to reinforcement rate. In Experiment 3, increasing the earn response requirement with a progressive-ratio schedule that reset only with a collect response increased the likelihood of accumulation when the collect and earn levers were 248 cm apart, even though such accumulation increased the next earn response requirement. Reinforcer accumulation is an understudied dimension of operant behavior that relates to the analysis of such phenomena as hoarding and self-control, in that they too involve accumulating versus immediately collecting or consuming reinforcers.     

价值计算决定何时与如何努力

优化努力的分配,最小化努力成本和最大化收益是各个领域的关键问题。本文梳理了基于努力的决策(effort-based decision-making)的理论与实证研究,讨论了努力的两面性：固有成本和潜在价值。通过拓展控制期望价值理论(Expected Value of Control, EVC),本研究探讨了影响努力的非社会与社会因素。探索人们何时以及如何付出努力的计算神经机制,有利于理解与促进社会互动中的努力行为,以及为干预精神疾病中动机缺失症状提供参考。     

Making life easier with effort: Basic findings and applied research on response effort

Early basic research showed that increases in required response effort (or force) produced effects that resembled those produced by punishment. A recent study by Alling and Poling determined some subtle differences between the two behavior-change strategies, but also confirmed that increasing required effort is an effective response-reduction procedure with enduring effects. In this paper we summarize basic research on response effort and explore the role of effort in diverse applied areas including deceleration of aberrant behavior, attention deficit hyperactivity disorder, oral habits, health care appointment keeping, littering, indexes of functional disability, and problem solving. We conclude that renewed interest in response effort as an independent variable is justified because of its potent effects and because the political constraints imposed on punishment- and reinforcement-based procedures have yet to be imposed on procedures that entail manipulations of response effort.     

The impact of perceived effort–reward imbalance on workplace bullying: also a matter of organizational identification

Work environments characterized by inadequate work conditions have been widely recognized as being particularly prone to the occurrence and exacerbation of bullying behavior. Accordingly, this longitudinal study aimed to explore whether the impact of effort–reward imbalance (ERI) on workplace bullying was mediated by a lower perception of organizational justice, and whether the association between ERI and perceptions of justice was moderated by organizational identification. In the current study, a sample of N = 195 Spanish employees from different occupational sectors filled in an online questionnaire at two different times with a time lag of 8 months. In line with the hypothesized moderated mediation model, results showed that organizational justice mediated the impact of ERI on workplace bullying. Moreover, the effect of perceived ERI on organizational justice was stronger for employees with low organizational identification. Overall, this study can contribute to better understanding how and when ERI boosts the risk of workplace bullying. Accordingly, early intervention designed to buffer the negative effects of ERI should focus on increasing individual levels of organizational identification.     

Pupillometry reveals processing load during spoken language comprehension

This study investigated processing effort by measuring peoples’ pupil diameter as they listened to sentences containing a temporary syntactic ambiguity. In the first experiment, we manipulated prosody. The results showed that when prosodic structure conflicted with syntactic structure, pupil diameter reliably increased. In the second experiment, we manipulated both prosody and visual context. The results showed that when visual context was consistent with the correct interpretation, prosody had very little effect on processing effort. However, when visual context was inconsistent with the correct interpretation, prosody had a large effect on processing effort. The interaction between visual context and prosody shows that visual context has an effect on online processing and that it can modulate the influence of linguistic sources of information, such as prosody. Pupillometry is a sensitive measure of processing effort during spoken language comprehension.     

Separating item-related electrophysiological indices of retrieval effort and retrieval orientation

The relationship between two classes of retrieval process-retrieval orientation and retrieval effort-was investigated using electrophysiological (ERP) and behavioural measures. ERPs were recorded during retrieval phases of exclusion tasks in which participants focused on retrieval of either phonological or semantic associates that were generated in a prior study phase. Participants were separated into two groups on the basis of the relative accuracy of their memory judgments in the retrieval tasks (high vs. low relative difficulty) as a means of assessing retrieval effort. The critical contrasts were between the ERPs evoked by unstudied test items separated according to group and emphasis of the retrieval task (semantic vs. phonological). Reliable differences according to task were evident in the high relative difficulty group only. This finding is consistent with the view that, for this task pair at least, ERPs are sensitive to the processes set in train in pursuit of task relevant information (retrieval orientations) only when relative difficulty is high.     

Rapid assessment of the effects of restraint on self-injury and adaptive behavior

We evaluated the effects of restraint on occurrences of self-injurious behavior (SIB) and adaptive responses exhibited by 2 individuals across eight response-effort conditions: baseline (no restraints); restraint sleeves without stays; restraints with 5, 10, 15, 20, or 25 thin metal stays; and restraints with five thick metal stays. From this analysis, we identified a restraint level for each participant that reduced SIB but did not inhibit adaptive responding.     

UTILIZING INCREASED RESPONSE EFFORT TO REDUCE CHRONIC HAND MOUTHING

The effects of increased response effort on levels of hand mouthing, leisure engagement, and adaptive elbow flexion were investigated with 2 individuals who had been diagnosed with profound disabilities. Arm restraints designed to alter the amount of physical effort necessary to engage in hand mouthing were used. Results indicated that the treatment strategy reduced levels of hand mouthing but produced only small to moderate reductions in levels of leisure engagement and adaptive elbow flexion. At follow-up, the effects of increased response effort on hand mouthing and leisure engagement were maintained for both participants; however, the restraints were associated with substantial reductions in adaptive elbow flexion for 1 participant.