Making Sense of Dynamic Systems: How Our Understanding of Stocks and Flows Depends on a Global Perspective

Stocks and flows (SF) are building blocks of dynamic systems: Stocks change through inflows and outflows, such as our bank balance changing with withdrawals and deposits, or atmospheric CO₂ with absorptions and emissions. However, people make systematic errors when trying to infer the behavior of dynamic systems, termed SF failure, whose cognitive explanations are yet unknown. We argue that SF failure appears when people focus on specific system elements (local processing), rather than on the system structure and gestalt (global processing). Using a standard SF task (n = 148), SF failure decreased by (a) a global as opposed to local task format; (b) individual global as opposed to local processing styles; and (c) global as opposed to local perceptual priming. These results converge toward local processing as an explanation for SF failure. We discuss theoretical and practical implications on the connections between the scope of attention and understanding of dynamic systems.     

Manipulated flow reduces downstream defensiveness

Flow is a psychological state people experience when performing highly challenging tasks with a high degree of skill. It is related to happiness, creativity, and productivity. In three experiments, we developed a manipulation of flow and assessed its effects on subsequent defensive behavior. In all three experiments, participants who played a game with more features of flow (e.g. engagement, match of challenge and skill, performance feedback) reported more feelings of flow (e.g. enjoyment, concentration and interest) and less downstream defensiveness. The results suggest that we developed a flexible, reliable manipulation of flow, and that inducing people to experience flow may reduce their subsequent defensive behavior.     

Effects of translational background motion on visual localization

Three subjects were asked to judge the position of small spots of light flashed before, during or after rapid translational motion of the background grating pattern. Mislocalization of the spots was observed when the background moved during or immediately after presentation of the spot. In both cases, mislocalization always occurred in the direction of the fixation point. Furthermore, this mislocalization occurred only when the background moved in the opposite direction to the visual half-field in which the spot appeared. That is to say, a spot to the right of the fixation point was mislocalized when its background moved to the left, but not when it moved to the right, and the converse was also true. This finding was interpreted as reflecting a long-term adaptation to the optokinetic stimulation that we experience during forward and backward locomotion.     

Traffic congestion,driver stress,and driver aggression

Drivers were interviewed over cellular telephones in high‐ and low‐congestion conditions during a single commute. During each interview, state measures of driver stress and driver behaviors were obtained. Behavior responses were subdivided into six categories: aggressive, information seeking, planning, minor self‐destructive, distraction, and relaxation techniques. Both state driver stress and aggression were greater in high‐ than in low‐congestion conditions. No other behavior category differed between low and high congestion. Multiple regressions were calculated to determine the predictors of state driver stress. In low congestion, time urgency predicted state driver stress, while aggression predicted driver stress in high congestion. In both conditions, a trait susceptibility toward viewing driving as generally stressful was predictive of state driver stress levels, which further strengthens the use of the Driving Behaviour Inventory—General as a predictor of “trait” driver stress. Females and males did not differentiate on state stress or any behavior category. Aggr. Behav. 25:409–423, 1999. © 1999 Wiley‐Liss, Inc.     

The Added Value of Studying Embodied Responses in Couple Therapy Research: A Case Study

This article reports on the added value of embodied responses identified through sympathetic nervous system (SNS) activity in couple therapy research. It focuses on moments of change and the timing of therapeutic interventions or therapeutic moves in a couple therapy session. The data for this single‐case study comprise couple therapy process videotapes recorded in a multi‐camera setting, and measurements of participants’ SNS activity. The voluntary participants were a marital couple in their late thirties and two middle‐aged male psychotherapists. The division into topic segments showed how the key issue of seeking help, which was found to comprise three separate components, was repeatedly dealt with in the session. SNS activity showed different degrees of synchronization between the couple, between the therapists, and between the couple and therapists during the dialogue pertaining to these three components. The issue of timing emerged as a complex, even ambivalent, phenomenon. Arousal in the therapists was in line with their therapeutic activity, whereas in the clients it was more anticipatory. The approach used here rendered visible some of the intensity that therapeutic dialogue can generate when dealing with issues of relationship change in the couple context and showed how this intensity can be dialogically regulated in the therapeutic system.     

Well‐being and pressures of daily life in two West Bank villages—Exploring context and history

Interest in the well‐being of people exposed to long‐term violence and conflict has tended to focus on measurable effects of acute traumatic events, while attention to the pressures of their daily living context is relatively new. Using qualitative and quantitative data from a 2005 survey of all female family caretakers in 2 neighbouring Israeli‐occupied West Bank villages (n = 820), we explored the associations of demographic, health‐related and contextual factors with reported pressures and WHO‐5 well‐being index scores. The final model explained 17.8% of the variance with negative associations between health‐related factors (“back‐aches,” “stomach aches” “psychological illness in the family”) and family‐related factors (“male head of household aggressive”, “male head of household physically violent”) and the WHO‐5 well‐being index scores. We found positive associations between socio‐economic factors (“standard of living”; “number of rooms”) and village‐related factors (“residency in village A/B”) and the WHO‐5 well‐being index score. Exploring the daily living context of villages A and B illuminated how the impact of historical and political events differed, even in villages that are geographically close. The paper lends support to calls for including politics and history in research on well‐being in contexts of long‐term violence and conflict.     

Associations of transcranial doppler velocity,age, and gender with cognitive function in children with sickle cell anemia in Nigeria

Children with sickle cell anemia (SCA) have elevated cerebral blood velocity relative to healthy peers. The primary aim of this study was to evaluate the association between cerebral blood velocity, measured by transcranial Doppler (TCD) ultrasound, age, and gender with cognitive function in children with SCA in Nigeria. Eighty-three children (M_age = 9.10, SD = 1.90 years; 55% female) with SCA in Nigeria completed cognitive assessments and a TCD ultrasound. The association between TCD velocity and measures of perceptual reasoning (Raven’s Progressive Matrices), working memory (WISC-IV Digit Span), and executive planning (Tower of London, TOL) were assessed. Results showed that elevated TCD velocity significantly predicted lower scores on TOL Time Violations and Total Problem-Solving Time when controlling for BMI, hemoglobin level, and parent education, suggesting that TCD velocity is related to the efficiency of executive function. Further, age was negatively related to children’s performance on the Ravens Matrices and TOL Total Correct, and boys showed greater deficits on the TOL Total Correct relative to girls. Moderation analyses for gender showed that there was a conditional negative association between TCD velocity and Digit Span for boys, but not for girls. Findings suggest that children with SCA in Nigeria with elevated TCD velocity are at risk for deficits in efficiency of executive planning, and boys with elevated TCD velocity are particularly at increased risk for deficits in auditory working memory. Implications of this study are important for interventions to reduce cerebral blood velocity and the use of TCD in this population.     

教学设计中的成绩表现和心流体验:基于认知负荷视角

教学设计是为优化教学效果而形成的教学实施方案。为提高学习表现,认知负荷理论认为在组织教学设计时需考虑内、外认知负荷两大因素,但少有研究关注学生在学习过程中的体验。本研究通过单词复合性操纵内在负荷,通过呈现方式操纵外在负荷,探究两类负荷对心流体验及表现的影响。结果发现,内在负荷对心流及表现均有影响,外在负荷仅在低水平组表现出对心流及表现的影响,另外内外负荷在低水平组的表现上存在交互作用。结果表明,教学设计中的内在负荷是影响心流及表现的稳定因素,外在负荷不仅受知识水平影响,其对表现的有效性还受内在负荷的调节。     

Narrow lanes and their effect on drivers’ behaviour at motorway roadworks

In recent years, more use of narrow lanes as a temporary traffic management scheme (TTMS) on UK motorway roadwork sections has been made. The rationale is to free up carriageway space, especially for sites with high traffic demands needing repairs. What remains to be determined is the impact of this work on traffic operation. This is important due to the need to manage traffic operational turbulence which could affect the capacity as well as safety levels in roadwork sections. Site observations (mainly using camcorders from overhead bridges) were made which uncovered two discernible patterns of driving behaviour where narrow lanes are implemented at roadworks, especially when heavy goods vehicles (HGVs) are present: (i) “avoiding” passing/overtaking HGVs travelling in the adjacent lanes and (ii) lane “repositioning” while passing/overtaking which might cause some turbulence to traffic operation. From one site, almost half of the passenger car drivers (including small vans) who were following a HGV on the adjacent lanes were avoiding passing that HGV. Also, nearly three quarters of the observed passenger cars, the passenger car drivers tried to position their vehicles as far away as possible, laterally, from the adjacent HGV while passing/overtaking that HGV in order to widen the lateral gap between their vehicles and the HGV. This resulted in driving too close to the edge of the road markings of their current lane away from the HGV. Therefore, this paper aims to report on the “avoiding” and lane “repositioning” behaviours to help inform traffic management teams/designers using narrow lanes as TTMS and make them aware of such behaviours (especially for motorway sections carrying high percentages of HGVs). Also, the finding from these observations were used in the development of a new micro-simulation model in order to evaluate the effect of such turbulence.