The role of nucleus accumbens and dorsolateral striatal D2 receptors in active avoidance conditioning

The role of dopamine (DA) in rewarding motivated actions is well established but its role in learning how to avoid aversive events is still controversial. Here we tested the role of D2-like DA receptors in the nucleus accumbens (NAc) and the dorsolateral striatum (DLS) of rats in the learning and performance of conditioned avoidance responses (CAR). Adult male Wistar rats received systemic, intra-NAc or intra-DLS (pre- or post-training) administration of a D2-like receptor agonist (quinpirole) or antagonist ((−)sulpiride) and were given two sessions in the two-way active avoidance task. The main effects observed were: (i) sulpiride and lower (likely pre-synaptic) doses of quinpirole decreased the number of CARs and increased the number of escape failures; (ii) higher doses of quinpirole (likely post-synaptic) increased inter-trial crossings and failures; (iii) pre-training administration of sulpiride decreased the number of CARs in both training and test sessions when infused into the NAc, but this effect was observed only in the test session when it was infused into the DLS; (iv) post-training administration of sulpiride decreased CARs in the test session when infused into the NAc but not DLS. These findings suggest that activation of D2 receptors in the NAc is critical for fast adaptation to responding to unconditioned and conditioned aversive stimuli while activation of these receptors in the DLS is needed for a slower learning of how to respond to the same stimuli based on previous experiences.     

Perceptions of unfairness in allocations between multiple recipients

This paper introduces a new model to explain perceptions of unfairness in resource allocations between multiple recipients. The model yields several novel predictions, all confirmed in a series of new empirical tests. For instance, while much prior research focuses on the differences between the judge’s share and others’ shares, we argue that people also care about differences between others’ shares. In particular, the presence of a single loser increases perceptions of unfairness. We also study individual variation in sensitivity to the single-loser dimension. Most centrally, we offer empirical support for the existence – indeed the prevalence – of ostraphobics, individuals with an acute sensitivity to being “ostracized” as a sole loser. We show that ostraphobics perceive unfairness more strongly than other types, are higher in need to belong and fear of negative evaluation, and are more prone to a heretofore unrecognized type of preference reversal with respect to fairness.     

Removing Inconsistencies in Assumption-based Theories Through Knowledge-Gathering Actions

In this paper, the problem of purifying an assumption-based theory KB, i.e., identifying the right extension of KB using knowledge-gathering actions (tests), is addressed. Assumptions are just normal defaults without prerequisite. Each assumption represents all the information conveyed by an agent, and every agent is associated with a (possibly empty) set of tests. Through the execution of tests, the epistemic status of assumptions can change from "plausible" to "certainly true", "certainly false" or "irrelevant", and the KB must be revised so as to incorporate such a change. Because removing all the extensions of an assumption-based theory except one enables both identifying a larger set of plausible pieces of information and renders inference computationally easier, we are specifically interested in finding out sets of tests allowing to purify a KB (whatever their outcomes). We address this problem especially from the point of view of computational complexity.     

Emotionally guiding our actions

If emotions have a rational role in action, then one challenge for accounting for how we can act rationally when acting emotionally is to show how we can guide our actions by our emotional considerations, seen as reasons. In this paper, I put forward a novel proposal for how this can be so. Drawing on the interconnection between emotions, cares and caring, I argue that, as the emotional agent is a caring agent, she can be aware of the emotional consideration as a pro tanto reason favouring an action choice and, even, as the reason for which she should act.     

On the role of indeterminism in libertarian free will

In a recent paper in this journal, “How should libertarians conceive of the location and role of indeterminism?” Christopher Evan Franklin critically examines my libertarian view of free will and attempts to improve upon it. He says that while Kane's influential [view] offers many important advances in the development of a defensible libertarian theory of free will and moral responsibility?…?[he made] “two crucial mistakes in formulating libertarianism” – one about the location of indeterminism, the other about its role – “both of which have helped fan the flame of the luck argument”. In this paper, I respond to Franklin's criticisms, arguing that, so far from making it significantly more difficult to answer objections about luck and control, as he claims, giving indeterminism the location and role I do makes it possible to answer such objections and many other related objections to libertarian free will. A central theme of this paper will emerge in my responses: In order to make sense of freedom of will in general and to do justice to the complex historical debates about it, one must distinguish different kinds of control agents may have over events and correspondingly different kinds of freedom they may possess.     

The relationship between justice and attitudes: An examination of justice effects on event and system-related attitudes

Research in organizational justice has always been interested in the relationship between justice and attitudes. This research often examines how different types of justice affect different attitudes, with distributive justice predicted to affect attitudes about specific events (e.g., performance evaluation) and procedural justice predicted to affect attitudes about organizations (e.g., organizational commitment). However, there is mixed support for these predictions. Moreover, this approach generally ignores the relationship between attitudes about the specific event and attitudes toward the organization. In this study we identify three alternative models of justice and attitudes. We use customer responses to complaint handling to test these alternative conceptualizations. Results generally support a mediated model, wherein event attitudes mediate the effect of justice perceptions on system-related attitudes. The implication of these findings for organizations and justice researchers are discussed.     

Information–movement coupling in developing cricketers under changing ecological practice constraints

Changing informational constraints of practice, such as when using ball projection machines, has been shown to significantly affect movement coordination of skilled cricketers. To date, there has been no similar research on movement responses of developing batters, an important issue since ball projection machines are used heavily in cricket development programmes. Timing and coordination of young cricketers (n = 12, age = 15.6 ± 0.7 years) were analyzed during the forward defensive and forward drive strokes when facing a bowling machine and bowler (both with a delivery velocity of 28.14 ± 0.56 m s⁻¹). Significant group performance differences were observed between the practice task constraints, with earlier initiation of the backswing, front foot movement, downswing, and front foot placement when facing the bowler compared to the bowling machine. Peak height of the backswing was higher when facing the bowler, along with a significantly larger step length. Altering the informational constraints of practice caused major changes to the information–movement couplings of developing cricketers. Data from this study were interpreted to emanate from differences in available specifying variables under the distinct practice task constraints. Considered with previous findings, results confirmed the need to ensure representative batting task constraints in practice, cautioning against an over-reliance on ball projection machines in cricket development programmes.     

On the futility of psychiatric diagnostic manuals (DSMs) and the return of personal agency

This article critiques the most recent version of the American Psychiatric Association's (1994) Diagnostic and Statistical Manual (DSM-IV). After pointing to the procedures employed in constructing the Manual, I note that unreliability of diagnosis is still a major problem and, more important, little attention has been paid to validity. Based on the mechanistic Kraepelinian model, the Manual contributes to the increasing medicalization of distress and directs clinicians to search for causes of unwanted behavior in biochemical anomalies. The person as agent is not part of the DSM diagnostic program. As an alternative to the DSM-IV, I propose a contextualist approach to understanding unwanted conduct. The person is treated as an agent who employs strategic actions to maintain a self-narrative. Strategic actions that fail to influence relevant others to supply warrants of social validation become the targets of clinical interventions.     

Efficient search under constraints and not working memory resources supports creative action emergence in a convergent motor task

Creative (original and functional) solutions to problems can be facilitated by guiding search behavior. According to cognitive models, when solving convergent tasks (tasks with few solutions), high available working memory (WM) resources and capacity can guide creative solution emergence via repeated (persistent) search within a solution subcategory. However, no clear associations have been found of WM capacity on creative outcomes when tasks require the individual to enact solutions in divergent doing tasks. This study further tested constraints on WM resources on search behavior and creative outcomes in a convergent doing task. Novices to combat sports were asked to repeatedly strike a target with the intent to achieve an individualized target force. In order to manipulate available WM resources, every ten strikes, participants were asked to recall and then retain a sequence of 5 digits (high load group: n = 21) or 2 digits (low load group: n = 21). The task constraints favored the functionality (or appropriateness) of a qualitatively distinct, non-obvious solution. Functionality was assessed using the force registered for each strike. Originality was assessed in terms of how infrequently actions occurred. Finally, search behavior was quantified based on changes in which limb was used and changes in which part of the limb was used from one strike to the next. There were no significant effects of WM load on creativity outcomes, solution search, or task success. Rather, task success was related to efficient search and creativity. Future research should focus on constraints (other than WM resources) that promote efficient search.