Mental representations of obligatory and prohibitory traffic signs

Every traffic sign conveys a single proposition about traffic conditions. Drivers must integrate this proposition with their goals and other known facts to decide on an appropriate action in what amounts to a deduction task. For example, imagine that you are driving a car and you want to turn right at an intersection but there is a no right turn sign. You have to assess the options and make a decision (reach a conclusion). Theoretical accounts from research about reasoning can be applied to how we understand traffic signs and make inferences from them. This study includes two experiments that analysed how people decide whether a situation is allowed or not, taking into account the information provided by one sign - obligatory or prohibitory - or two signs - two obligatory or two prohibitory signs. The number of signs, that is, the complexity of the driving scene, was a key factor in this study. The two experiments differ in the presentation format of the two-sign experimental condition. In the first experiment, the signs were presented as two isolated signs. In the second experiment, the two signs were embedded in one. Equivalent results were found whether two isolated signs or two embedded signs were shown. When an obligatory sign was used at the junction, faster responses were obtained for allowed manoeuvres than for those not allowed. When a prohibitory sign was used, the results were the opposite. However, the advantage of prohibitory signs in the not-allowed situation was not replicated when people had to collect information from two prohibitory signs. Results showed that people integrate two obligatory sign messages - informing where one can go - more easily than two prohibitory sign messages - informing where not to go. Therefore, it could be said that each traffic sign elicits an internal mental model elaboration in which forbidden actions are explicitly labelled by means of attached "mental footnotes" indicating the epistemic status of "prohibitory information."     

Suicidal ideation in college students varies across semesters: the mediating role of belongingness

The interpersonal-psychological theory of suicidal behavior (Joiner, 2005) proposes that the need to belong is fundamental; when met it can prevent suicide and when thwarted it can substantially increase the risk for suicide. We investigate one source of group-wide variation in belongingness among college students--changes in the social composition of college campuses across academic semesters--as an explanation for variation in suicidal ideation across the academic year. Our results indicate that in a sample of college students at a large southern state university (n = 309), suicidal ideation varied across academic semesters, with highest levels in summer compared to both spring and fall. Differences in suicidal ideation between summer and spring were, in large part, accounted for by belongingness. Theoretical, as well as practical, implications are discussed regarding mechanisms for seasonal variation in suicidal ideation.     

Effect of the light intensity upon the agonistic behaviour of juvenile of white‐seabream (Diplodus sargus cadenati de la Paz,Bauchot and Daget, 1974)

Ambient light levels were manipulated to vary potential predation risk, and aggressive behaviour was examined. Juveniles of white‐seabream (Diplodus sargus cadenati) interacted aggressively more frequently at intermediate light intensity (500 lux), being agonistic interactions at higher (3000 lux) or lower (5 lux) illumination less frequent. Aggr. Behav. 30:313–318, 2004. © 2004 Wiley‐Liss, Inc.     

A Critical Analysis of Approaches to the Development of Preventive Interventions for Subcultural Groups

The ultimate success of preventive interventions relies on their ability to engage and influence the growing presence of subcultural groups. To encourage and guide the development of effective preventive intervention for subcultural groups, four approaches are described, illustrated, and critiqued with respect to their considerations of cultural fit, reach, efficacy and adoption. Those approaches are (a) the prevention research cycle, (b) cultural adaptations of evidence-based interventions, (c) investigator-initiated culturally-grounded approaches, and (d) community-initiated indigenous approaches. Special attention is given to recent advances in the specification of stages in the cultural adaptation of interventions. The paper closes with some conclusions and topics in need of greater attention.     

Sadness, suicide, and their association with video game and internet overuse among teens: results from the youth risk behavior survey 2007 and 2009

We investigated the association between excessive video game/Internet use and teen suicidality. Data were obtained from the 2007 and 2009 Youth Risk Behavior Survey (YRBS), a high school-based, nationally representative survey (N = 14,041 and N = 16,410, respectively). Teens who reported 5 hours or more of video games/Internet daily use, in the 2009 YRBS, had a significantly higher risk for sadness (adjusted and weighted odds ratio, 95% confidence interval = 2.1, 1.7-2.5), suicidal ideation (1.7, 1.3-2.1), and suicide planning (1.5, 1.1-1.9). The same pattern was found in the 2007 survey. These findings support an association between excessive video game and Internet use and risk for teen depression and suicidality.     

The dimensional nature of same-different discrimination behavior in pigeons

We studied the dimensional nature of same-different discrimination behavior in pigeons. Birds first learned to discriminate between simultaneously presented displays of 16 identical items (Same arrays) and 16 nonidentical items (Different arrays), conditional on the color of the background. After discrimination mastery, we tested the birds with Mixture arrays comprising both identical and nonidentical items. Accuracy increased and reaction time decreased as the disparity in entropy (a measure of variability) between the arrays increased. As well, within each entropy disparity level, lower entropy values were more discriminable than higher entropy values. These results accord with a logarithmic relation between entropy and discriminative behavior and, thus, with the idea that the discrimination of Same from Different arrays follows Weber's Law.     

Explaining the paradoxical rejection-aggression link: the mediating effects of hostile intent attributions, anger, and decreases in state self-esteem on peer rejection-induced aggression in youth

People are strongly motivated to feel accepted by others. Yet when faced with acute peer rejection they often aggress against the very peers they desire acceptance from, which may lead to further rejection. The present experiment tests three potential mediators of aggressive responses to acute peer rejection in the critical developmental stage of early adolescence. Participants (N=185, M(age)=11.5 years) completed personal profiles that were allegedly evaluated online by peers. After receiving negative or neutral peer feedback, participants could aggress against the same peers who had evaluated them. Rejected participants attributed more hostile intent to the peers, were angrier, showed a greater reduction in state self-esteem, and were more aggressive. Mediational analyses showed that hostile intent attributions mediated the acute peer rejection-aggression relationship, whereas increases in anger and decreases in state self-esteem did not. Thus, acute peer rejection evokes hostile intent attributions that, in turn, lead to aggressive reactions.     

Metabolic costs of aggressive behaviour in the Siamese fighting fish,Betta splendens

Aggressive conflicts between males are often resolved by means of multiple ritualized agonistic displays without damaging escalation. Apparently, in such cases by using those displays opponents exchange important motivational and physical information on which they base a decision to stay or leave the interaction. In the Siamese fighting fish, the time spent spreading the dorsal fin and erecting the gill coverts predicts who will be the winner or loser of the interaction. Two experiments were carried out to study whether display performance might be costly. First, oxygen consumption was measured during mirror‐image stimulation. This experiment showed that oxygen consumption was positively correlated with gill cover erection and dorsal fin spread. In the second experiment, a fight between two opponents was simulated and the oxygen consumption of the expected winner and loser was compared. Metabolic rates were not different between winners and losers before and during the fight, but winners showed higher oxygen consumption in the night after the fight. These results are in accordance with costs of display performance and with long‐lasting physiological consequences of winning or losing a fight. Aggr. Behav. 32:1–7, 2006. © 2006 Wiley‐Liss, Inc.     

The imprecise impermissivist’s dilemma

Synthese - Impermissivists hold that an agent with a given body of evidence has at most one rationally permitted attitude that she should adopt towards any particular proposition. Permissivists...