Neural correlates of intertemporal choice in aggressive behavior

People often have to make decisions between immediate rewards and more long-term goals. Such intertemporal judgments are often investigated in the context of monetary choice or drug use, yet not in regard to aggressive behavior. We combined a novel intertemporal aggression paradigm with functional neuroimaging to examine the role of temporal delay in aggressive behavior and the neural correlates thereof. Sixty-one participants (aged 18–22 years; 37 females) exhibited substantial variability in the extent to which they selected immediate acts of lesser aggression versus delayed acts of greater aggression against a same-sex opponent. Choosing delayed-yet-more-severe aggression was increased by provocation and associated with greater self-control. Preferences for delayed aggression were associated with greater activity in the ventromedial prefrontal cortex (VMPFC) during such choices, and reduced functional connectivity between the VMPFC and brain regions implicated in motor impulsivity. Preferences for immediate aggression were associated with reduced functional connectivity between the VMPFC and the frontoparietal control network. Dispositionally aggressive participants exhibited reduced VMPFC activity, which partially explained and suppressed their preferences for delayed aggression. Blunted VMPFC activity may thus be a neural mechanism that promotes reactive aggression towards provocateurs among dispositionally aggressive individuals. These findings demonstrate the utility of an intertemporal framework for investigating aggression and provide further evidence for the similar underlying neurobiology between aggression and other rewarding behaviors.     

The role of ecological validity in hazard perception assessment

Hazard perception is one of the few quantifiable components of driving competency that can explain the high crash risk of novice drivers (see Horswill & McKenna, 2004). Some studies focused on investigating the stimulus part of hazard perception items by comparing several design features of the displayed traffic scenarios (e.g. Malone et al., 2012; Scialfa et al., 2013). Other empirical studies have been conducted to address the reaction part of hazard perception items (e.g. Vlakveld, 2014). Among others, existing hazard perception tests differ with respect to the ecological validity – the similarity to real-world demands – of the task that has to be completed by the participants (simple reaction, hazard localization, simulated driving, etc.). Based on the findings of general expertise research (see Glaser & Chi, 1988), the hypothesis of the present experiment was that an increased ecological validity of a hazard perception task has a positive effect on the magnitude of performance differences between more and less experienced drivers. 104 learner drivers and 51 experienced drivers were randomly assigned either to a less ecological valid version (multiple choice task) or a higher ecological valid version (reaction task) of a hazard perception test. In both conditions, the same 20 animated hazardous or non-hazardous traffic scenarios were presented. Overall, the experienced drivers outperformed the learner drivers. Principally, both of the applied versions of the test provided a criterion valid measure of driving expertise. However, increasing the ecological validity of the test by using a reaction task was especially beneficial for certain types of scenarios, leading to higher expertise-related differences. In addition, the reaction task provides response time measure as a further valid performance indicator. This allows the identification of those participants who are indeed able to detect a hazard in a certain scenario, but still have deficits in response time, compared to more experienced drivers. According to the present study, it is recommended to choose the reaction task over the multiple choice task to test hazard perception. Whether a further increase in ecological validity of the task would be useful, should be tested empirically in future research.     

多时点结果跨期选择的决策效应及其心理机制

多时点结果跨期选择涉及两个及两个以上多个时点结果的权衡, 正日益成为跨期选择的研究重点。现有研究主要从两时点结果和序列结果两方面深入探讨了多时点结果跨期选择中的诸多决策效应, 包括：隐藏的零效应、象征效应、额外金额效应、前端金额效应以及序列效应, 并运用序列模型和权衡模型对上述决策效应进行阐释。未来还应深入探索同时涉及损益结果混合的多时点结果跨期选择, 运用决策过程追踪技术揭示决策效应的过程机制。     

Control by reinforcers across time and space: A review of recent choice research

Reinforcers affect behavior. A fundamental assumption has been that reinforcers strengthen the behavior they follow, and that this strengthening may be context‐specific (stimulus control). Less frequently discussed, but just as evident, is the observation that reinforcers have discriminative properties that also guide behavior. We review findings from recent research that approaches choice using nontraditional procedures, with a particular focus on how choice is affected by reinforcers, by time since reinforcers, and by recent sequences of reinforcers. We also discuss how conclusions about these results are impacted by the choice of measurement level and display. Clearly, reinforcers as traditionally considered are conditionally phylogenetically important to animals. However, their effects on behavior may be solely discriminative, and contingent reinforcers may not strengthen behavior. Rather, phylogenetically important stimuli constitute a part of a correlated compound stimulus context consisting of stimuli arising from the organism, from behavior, and from physiologically detected environmental stimuli. Thus, the three‐term contingency may be seen, along with organismic state, as a correlation of stimuli. We suggest that organisms may be seen as natural stimulus‐correlation detectors so that behavioral change affects the overall correlation and directs the organism toward currently appetitive goals and away from potential aversive goals. As a general conclusion, both historical and recent choice research supports the idea that stimulus control, not reinforcer control, may be fundamental.     

Closing the gap between behavior and models in route choice: The role of spatiotemporal constraints and latent traits in choice set formation

A considerable gap exists between the behavioral paradigm of choice set formation in route choice and its representation in route choice modeling. While travelers form their viable choice set by retaining routes that satisfy spatiotemporal constraints, existing route generation techniques do not account for individual-related spatiotemporal constraints. This paper reduces the gap by proposing a route choice model incorporating spatiotemporal constraints and latent traits. The proposed approach combines stochastic route generation with a latent variable semi-compensatory model representing constraint-based choice set formation followed by compensatory choice. The model is applied to data focusing on habitual commuting route choice behavior in morning peak hours. Results show (i) the possibility of inferring spatiotemporal constraints from considered routes, (ii) the importance of incorporating spatiotemporal constraints and latent traits in route choice models, and (iii) the linkage between spatiotemporal constraints and time saving, spatial and mnemonic abilities.     

Israeli Students' Perspectives Concerning Determinants of Intelligence

Abstract

Students' attitudes toward the nature versus nurture controversy pertaining to a variety of critical phenomena in the intelligence domain were assessed. A student inventory was constructed, pretested, and group administered to 269 students in various academic institutions in northern Israel, and comparisons were made between various sex, social, and ethnic groups. The majority of the students maintained that environment is the main factor influencing both personality and intelligence. Environment and an Environment x Heredity interaction were the most popular categories used to explain various generalizations about differences in ability, particularly among lower-class students. Students of Western origin were more inclined to adopt an environmental perspective on differences in IQ than were their Eastern counterparts. No sex differences were observed.     

Concurrent-chains schedules as a method to study choice between alcohol-associated conditioned reinforcers

An extensive body of research using concurrent-chains schedules of reinforcement has shown that choice for one of two differentially valued food-associated stimuli is dependent upon the overall temporal context in which those stimuli are embedded. The present experiments examined whether the concurrent chains procedure was useful for the study of behavior maintained by alcohol and alcohol-associated stimuli. In Experiment 1, rats responded on concurrent-chains schedules with equal variable-interval (VI) 10-s schedules in the initial links. Across conditions, fixed-interval schedules in the terminal links were varied to yield 1∶1, 9∶1, and 1∶9 ratios of alcohol delivery. Initial-link response rates reflected changes in terminal-link schedules, with greater relative responding in the rich terminal link. In Experiment 2, terminal-link schedules remained constant with a 9∶1 ratio of alcohol delivery rates while the length of two equal duration initial-link schedules was varied. Preference for the rich terminal link was less extreme when initial links were longer (i.e., the initial-link effect), as has been previously reported with food reinforcers. This result suggests that the conditioned reinforcing value of an alcohol-associated stimulus depends on the temporal context in which it is embedded. The concurrent-chains procedure and quantitative models of concurrent chains performance may provide a useful framework within which to study how contextual variables modulate preference for drug-associated conditioned reinforcers.     

SAVING THE BEST FOR LAST? A CROSS-SPECIES ANALYSIS OF CHOICES BETWEEN REINFORCER SEQUENCES

Two experiments were conducted to compare choices between sequences of reinforcers in pigeon (Experiment 1) and human (Experiment 2) subjects, using functionally analogous procedures. The subjects made pairwise choices among 3 sequence types, all of which provided the same overall reinforcerment rate, but differed in their temporal patterning. Token reinforcement schedules were used in both experiments and the type of exchange schedule varied across blocks of sessions. Some conditions permitted immediate exchange of tokens for consumable reinforcers (food for pigeons, video access for humans); in other conditions, tokens accumulated and were exchanged for consumable reinforcers only at the end of the sequence. Choice patterns in the immediate-exchange conditions were generally similar across species, with both pigeons and humans preferring sequences with the shortest delay to the initial reinforcer in the series. The results are broadly consistent with models of temporal discounting expanded to include the impact of sequences of delayed reinforcers acting in parallel from the time of the choice. Preferences were less consistent with discounting models in the delayed exchange conditions. Questionnaire data gathered at the end of the experiment were consistent with prior results of questionnaire studies, but showed no straightforward relation to the observed choice patterns, urging caution in the extrapolation of results from one decision-making domain to the other.     

Normative influence on retirement savings decisions: Do people care what employers and the government want?

The need for Australians to increase retirement savings has been widely promoted. Yet our understanding of the motivations of individuals to save at a higher rate remains sparse. This article reports the findings of a survey of superannuation fund members and their intentions to contribute more to superannuation and to manage their investment strategy. The article uses the theory of planned behaviour to focus on the important motivational influence of social norms. Formative research identified a number of influential social referents. Among identified referents, the study found that spouses appear to be the primary source of social influence for retirement savings decisions. The government and employers appear to exert little influence, and financial advisors and superannuation funds take up the middle ground of social influence. Possibilities for interventions designed to influence behaviour are discussed; however, conclusions are tempered by the fact that correspondence between intention and behaviour is not tested in the present research.     

The preference for symmetry in flower-naïve and not-so-naïve bumblebees

Truly flower-naïve bumblebees, with no prior rewarded experience for visits on any visual patterns outside the colony, were tested for their choice of bilaterally symmetric over asymmetric patterns in a radial-arm maze. No preference for symmetry was found. Prior training with rewarded black and white disks did, however, lead to a significant preference for symmetry. The preference was not specific to symmetry along the vertical axis: a preference for horizontal symmetry was found as well. The results challenge the notion that a preference for bilateral symmetry is unlearned. The preference for symmetry was the product of non-differential conditioning.