The statistics of cognitive variability: Explaining common patterns in individuals, groups and financial markets.

Psychological variability (i.e., "noise") displays interesting structure which is hidden by the common practice of averaging over trials. Interesting noise structure, termed 'stylized facts', is observed in financial markets (i.e., behaviors from many thousands of traders). Here we investigate the parallels between psychological and financial time series. In a series of three experiments (total N = 202), we successively simplified a market-based price prediction task by first removing external information, and then removing any interaction between participants. Finally, we removed any resemblance to an asset market by asking individual participants to simply reproduce temporal intervals. All three experiments reproduced the main stylized facts found in financial markets, and the robustness of the results suggests that a common cognitive-level mechanism can produce them. We identify one potential model based on mental sampling algorithms, showing how this general-purpose model might account for behavior across these very different tasks.

Archerfish foraging success varies with immediate competition level but not group size.

Group living can lead to kleptoparasitism, the theft of resources by competitors. Under such conditions, foragers may alter their behavior to minimize competition. However, it is unclear how such behavioral changes impact foraging performance. Archerfish (Toxotes spp.) are a good model for investigating the behavioral responses to kleptoparasitism, as their hunting method (shooting waterjets at insects perched above the water) leaves them vulnerable to theft. They must hit the target prey with sufficient force to dislodge it; thus, the prey may land some distance away from the shooter. Kleptoparasitism rates increase with group size in archerfish, and individuals alter their behavior around conspecifics. We investigated whether group size affected shooting success, using 7-spot archerfish T. chatareus. We considered a fish's shot to be successful if it knocked a fly, placed on a transparent platform above the tank, into the water. The probability of shooting success was modeled as a function of group size, aiming duration, nearest neighbor distance and position, and trial number. We found no effect of group size, aiming duration, or nearest neighbor distance or position on shooting success. Shooting success increased as trials progressed, likely due to the fish becoming more familiar with the task. We also found no change in the kleptoparasitism rate between group sizes. Instead, the likelihood of the shooter consuming the prey depended on the types of competition present at the time of shooting. We suggest that archerfish shooting behavior can be influenced by the presence of conspecifics in ways not previously considered.

Plants buffer some of the effects of a pair of cadmium-exposed zebrafish on the un-exposed majority.

Certain individuals have a disproportionate effect on group responses. Characteristics may include susceptibility to pollutants, such as cadmium (Cd), a potent trace metal. Here, we show how a pair of Cd-exposed individuals can impact the behavior of unexposed groups. We used behavioral assessments to characterize the extent of the effects of the Cd-exposed individuals on group boldness, cohesion, foraging, activity, and responses to plants. We found that groups with a pair of Cd-exposed fish remained closer to novel stimuli and plants than did groups with untreated (control) fish. The presence of plants reduced Cd-induced differences in shoal cohesion and delays feeding in male shoals. Shoals with Cd- and water-treated fish were equally active. The results suggest that fish acutely exposed to environmentally relevant Cd concentrations can have profound effects on the un-exposed majority. However, the presence of plants may mitigate the effects of contaminants on some aspects of social behavior.

Analyzing retraction responses of Tubifex tubifex (Oligochaeta: Naididae) colonies to copper treatments through a digital image analysis approach for developing early biological warning systems.

Biological monitoring and assessments are commonly used for sustainable ecosystem management. Oligochaetes are found in various freshwater ecosystems and have been used as indicators of water quality and for the biological assessment of aquatic ecosystems. Among aquatic oligochaetes, the sludge worm Tubifex tubifex (Oligochaeta, Naididae) is tolerant to organic pollution and has been used as a biomonitoring indicator of toxicity and organic pollution. In this study, we investigated the response of worm colonies to copper (CuSO4) treatments (0.01, 0.05, 0.1, 0.5, and 1.0 mg/L) in an observation cage (100 mL beaker) for 30 min. Using a digital image analysis approach, we measured the changes in the colony image area between pre- and post-copper treatment. After copper treatment, the colony image area tended to decrease, even at low copper concentrations. In addition, the colony areas did not recover to their original levels at high concentrations, although those at low concentrations did. Area decreased proportional to the logarithm of the copper concentration. Finally, our results present the possible use of the retraction responses of Tubifex tubifex colonies to chemical disturbances as early biological warning systems.

Group Movement in Entomopathogenic Nematodes: Aggregation Levels Vary Based on Context.

Maintenance of an aggregated population structure implies within-species communication. In mixed-species environments, species-specific aggregations may reduce interspecific competition and promote coexistence. We studied whether movement and aggregation behavior of three entomopathogenic nematode species changed when isolated, as compared to mixed-species arenas. Movement and aggregation of Steinernema carpocapsae, S. feltiae and S. glaseri were assessed in sand. Each species demonstrated significant aggregation when alone. Mixed-species trials involved adding two species of nematodes, either combined in the center of the arena or at separate corners. While individual species became less aggregated than in single-species conditions when co-applied in the same location, they became more aggregated when applied in separate corners. This increased aggregation in separate-corner trials occurred even though the nematodes moved just as far when mixed together as they did when alone. These findings suggest that maintenance of multiple species within the same habitat is driven, at least in part, by species-specific signals that promote conspecific aggregation, and when the species are mixed (as occurs in some commercial formulations involving multiple EPN species), these signaling mechanisms are muddled.

Safety climate and safety behaviors: Adapting and validating a positively worded safety climate scale through the time-lagged approach.

BACKGROUND: Contemporary literature raises serious questions about the inclusion of negatively worded items in the safety climate scale. Despite these reservations, limited efforts have been made to address this shortcoming. OBJECTIVE: The present study aims to adapt and empirically validate the ten-items group-level safety climate scale with the purpose of replacing negatively worded items with positively worded ones after a thorough validation process. The present study is one of the first to propose an empirically validated group-level safety climate scale that uses positive items to measure the safety climate construct. METHODS: Study 1 was conducted using a sample of 135 participants. Study 2 used a time-lagged approach to validate the scale, with a sample of 173 production workers from six oil and gas organizations in Malaysia. The Partial Least Squares Structural Equation Modeling (PLS-SEM) method was used to test the hypothesized relationships. RESULTS: In Study 1, the results of the exploratory factor analysis showed good reliability for the revised scale. In Study 2, the results of the PLS-SEM analysis demonstrated a positive relationship between safety climate and safety behaviors, thereby validating the revised and translated scale of safety climate. CONCLUSION: The revised safety climate scale will not only improve data quality, but it will also increase response rates. Additionally, the revised scale will assist managers in understanding the true perceptions of safety climate in their organization, regardless of the cultural context in which the scale is used.

A Pair of Cadmium-exposed Zebrafish Affect Boldness and Landmark use in the Un-exposed Majority.

Some individuals have a disproportionate effect on group responses. These individuals may possess distinct attributes that differentiate them from others. These characteristics may include susceptibility to contaminant exposure such as cadmium, a potent trace metal present in water and food. Here, we tested whether a pair of cadmium-exposed individuals could exert an impact on the behavior of the unexposed majority. We used behavioral assessments to characterize the extent of the effects of the cadmium-exposed pair on group boldness, cohesion, activity and responses to landmarks. We found that groups with a pair of cadmium-exposed fish approached and remained closer to novel stimuli and landmarks than did groups with pairs of fish treated with uncontaminated water (control). Shoals with cadmium and water treated fish exhibited similar levels of cohesion and activity. The results suggest that fish acutely exposed to environmentally-relevant cadmium concentrations can have profound effects on the un-exposed majority.

Lateral incivility, nursing students, and the academic environment: A modified epidemiological triangle.

The traditional epidemiological triangle identifies an infectious disease causing agent, a susceptible host to house the agent, and an environment conducive to the agent's proliferation and sustenance. Social epidemiology expands this basic triangle to address health determinants, social inequities, and heath disparities related to and encountered by vulnerable populations. A group is considered vulnerable if it is susceptible to poor physical, psychological, spiritual, social, or emotional health, attack, and censure or criticism. Nursing students fulfill these criteria for vulnerability. Lateral student-to-student incivility as the disease causing agent, nursing students as the susceptible hosts, and the academic and clinical learning environments reflect a modified epidemiological triangle. Nursing students experience physical, social, and emotional problems from experiencing and witnessing incivility. Students replicate modeled incivility behaviors. Learning may be negatively compromised. Oppressed group behavior is presented as one cause of lateral incivility. The transmission of incivility behaviors as the disease causing agent can be interrupted through civility education offered to nursing student hosts and a no tolerance stance against incivility in the academic learning environment. Cognitive Rehearsal is an evidence-based strategy to teach nursing students how to confront incivility victimization.

A pair of cadmium-exposed zebrafish affect social behavior of the un-exposed majority.

To account for global contamination events, we must identify direct and indirect pollutant effects. Although pollutants can have direct effects on individuals, it is unknown how a few contaminated individuals affect groups, a widespread social organization. We show environmentally relevant levels of cadmium (Cd) can have indirect social effects revealed in the social context of a larger group. Cd-contaminated individuals had poor vision and more aggressive responses, but no other behavioral effects. The presence of experienced Cd-exposed pairs in the groups had an indirect effect on the un-exposed individual's social interactions leading to the shoal becoming bolder and moving closer to a novel object than control groups. Because a few directly affected individuals could indirectly affect social behavior of the un-exposed majority, we believe that such acute but potentially important heavy metal toxicity could inform reliable predictions about the consequences of their use in a changing world.

A Systems Biology Approach for Addressing Cisplatin Resistance in Non-Small Cell Lung Cancer.

Translational research in medicine, defined as the transfer of knowledge and discovery from the basic sciences to the clinic, is typically achieved through interactions between members across scientific disciplines to overcome the traditional silos within the community. Thus, translational medicine underscores 'Team Medicine', the partnership between basic science researchers and clinicians focused on addressing a specific goal in medicine. Here, we highlight this concept from a City of Hope perspective. Using cisplatin resistance in non-small cell lung cancer (NSCLC) as a paradigm, we describe how basic research scientists, clinical research scientists, and medical oncologists, in true 'Team Science' spirit, addressed cisplatin resistance in NSCLC and identified a previously approved compound that is able to alleviate cisplatin resistance in NSCLC. Furthermore, we discuss how a 'Team Medicine' approach can help to elucidate the mechanisms of innate and acquired resistance in NSCLC and develop alternative strategies to overcome drug resistance.

Zebrafish (Danio rerio) shoaling in light and dark conditions involves a complex interplay between vision and lateral line.

We know little about how - or even if in some species - fish shoal in darkness. We hypothesized that 'dark shoaling' occurs in zebrafish and therefore must depend upon lateral line sensory input. Shoaling in groups of five adult zebrafish was analyzed with motion tracking software. We measured average inter-individual distance, time near the arena wall (thigmotaxis zone) and total distance traveled under normal room light, and in near-complete darkness (infrared light at 850 nm). These observations were repeated in fish treated with cobalt chloride (CoCl2), which ablates lateral line function. In untreated controls, dark shoaling was reduced compared to in light, but nonetheless still present. Elimination of lateral line sensory input by CoCl2 treatment similarly reduced, but did not eliminate, shoaling under both light and dark. Our findings indicate that normal zebrafish shoaling in light or dark requires both visual and lateral line inputs, with neither alone sufficient for normal shoaling.

Analysis of group behavior based on sharing heterogeneous roles in a triad using a coordinated drawing task.

Humans often share roles and aim to achieve a group goal based on sociality, which is the tendency to spontaneously involve oneself with others. Cognitive science, psychology, and neuroscience studies suggest that in such planned coordination, adjusting one's own actions based on other roles is crucial for high task performance. However, the mechanisms of complex and dynamically planned coordination, such as non-verbal group behavior with three or more members, remain to be fully investigated. This study introduced a coordinated drawing task in a triad, quantitatively analyzed non-verbal group behavior based on sharing heterogeneous roles, and investigated an important role. Participant triads engaged in the task repeatedly by operating reels to change thread tensions and moving a pen connected to the three threads to draw an equilateral triangle. Then, the three roles (pulling, relaxing, and adjusting) had to be shared. The pulling and relaxing roles served to move the pen as if an operator pulled it closer to the hand and to support the pen's movement, respectively. However, these roles alone could not draw a side considering the task specification. The adjusting role needed to change the tension flexibly and maintain an overall balance. In the experiment, we measured the pen positions and tensions, and established statistical models to fit the analyzed data. The results estimated that the action in the adjusting role was related to the improved performance of faster drawing on a side. This role may moderately intervene in the actions by the other roles and fine-tune without disturbing the pen's smooth movement while avoiding great pen deviation. Our findings may suggest the crucial role as a facilitator that handles resiliently in non-verbal coordinated behavior of a triad, and contribute to our understanding of social interactions.

Differential analysis of negative geotaxis climbing trajectories in Drosophila under different conditions.

The decline of Drosophila climbing behavior is one of the common phenomena of Drosophila aging. The so-called negative geotaxis refers to the natural upward climbing behavior of Drosophila melanogaster after it oscillates to the bottom of the test tube. The strength of climbing ability is regarded as the index of aging change of D. melanogaster. At present, many laboratories use the percentage of 10 fruit flies climbing a specific height in 5 s as a general indicator of the climbing ability of fruit flies. This group research index ignores the climbing performance of a single fruit fly, and the climbing height belongs to the concept of vertical distance in physics, which cannot truly and effectively reflect the concept of curve distance in the actual climbing process of fruit flies. Therefore, based on the image processing algorithm, we added an experimental method to draw the climbing trajectory of a single fruit fly. By comparing the differences in climbing behavior of fruit flies under different sex, group or single, oscillation condition or rotation inversion condition, we can find that the K-Nearest Neighbor target detection algorithm has good applicability in fruit fly climbing experiment, and the climbing ability of fruit flies decreases with age. Under the same experimental conditions, the climbing ability of female fruit flies was greater than that of male fruit flies. The climbing track length of a single fruit fly can better reflect the climbing process of a fruit fly.

Signal Transduction Network Principles Underlying Bacterial Collective Behaviors.

Bacteria orchestrate collective behaviors and accomplish feats that would be unsuccessful if carried out by a lone bacterium. Processes undertaken by groups of bacteria include bioluminescence, biofilm formation, virulence factor production, and release of public goods that are shared by the community. Collective behaviors are controlled by signal transduction networks that integrate sensory information and transduce the information internally. Here, we discuss network features and mechanisms that, even in the face of dramatically changing environments, drive precise execution of bacterial group behaviors. We focus on representative quorum-sensing and second-messenger cyclic dimeric GMP (c-di-GMP) signal relays. We highlight ligand specificity versus sensitivity, how small-molecule ligands drive discrimination of kin versus nonkin, signal integration mechanisms, single-input sensory systems versus coincidence detectors, and tuning of input-output dynamics via feedback regulation. We summarize how different features of signal transduction systems allow groups of bacteria to successfully interpret and collectively react to dynamically changing environments.

A protocol for analyzing repeated measures of online group behavior.

In this article, we feature a novel protocol that enables the analysis of repeated measures of online group behavior. The protocol accounts for (1) the nested hierarchy of the data with weeks nested in persons, and persons nested in weeks, and (2) the temporal nature of the behavior at the early, mid, and late periods of each week. To manage and analyze such data in a general way, we first give an illustration of the data structure. Thereafter, we propose a five-step Courtney-Fanguy-Costley protocol that (1) considers the data structure, (2) defines the levels of data, (3) considers variable variation, timing, and necessary aggregation, (4) ensures necessary variation, and (5) specifies null and mixed-effects models. We also provide exemplary R code for readers to replicate our approach.•A general five-step protocol for analyzing repeated measures of online group behavior is offered.•A description of the complex nested data structure is offered.•Users can simulate data in R to run through the protocol.

Why do people self-sacrifice for their country? The roles of identity fusion and empathic concern.

Identity fusion with a group, a feeling of connection with it, is a good predictor of extreme pro-group behavior, an action to favor or protect the group, including self-sacrifice. Relational ties and personal distress (self-oriented emotional reaction; e.g., anxiety, distress) toward ingroup members in need have been evaluated separately as mediators of the relationship between identity fusion and pro-group self-sacrifice. Another mediator could be empathic concern (other-oriented emotional reaction; e.g., compassion, sympathy), but it has not been considered in the literature. We related those three mediators in a model. The objective was to analyze whether relational ties mediate the relationship between identity fusion and pro-country self-sacrifice whereas both empathic concern and personal distress mediate the association between relational ties and pro-country self-sacrifice. We expected that identity fusion with the country leads to more relational ties, which in turn evokes both empathic concern and personal distress, and those emotional reactions promote more and less pro-country self-sacrifice, respectively, with more effect of empathic concern than personal distress. We considered the country as the group reference because it is the most used in identity fusion research. In a sample of university students (N = 539), the results supported this model: Identity fusion promoted relational ties, which in turn evoked empathic concern and personal distress. Then, the last two variables predicted more and less self-sacrifice, respectively, with more effect of empathic concern than personal distress. We discussed the theoretical implications of the model, especially the relationship of identity fusion with empathic concern and personal distress-traditional explanations for pro-group behavior-considering the different motivations associated to both emotional reactions. Despite the limitations associated with the measurements, the data supported the model that relates variables not previously explored jointly.

Ability to share emotions of others as a foundation of social learning.

The natural habitats of most species are far from static, forcing animals to adapt to continuously changing conditions. Perhaps the most efficient strategy addressing this challenge consists of obtaining and acting upon pertinent information from others through social learning. We discuss how animals transfer information via social channels and what are the benefits of such exchanges, playing out on different levels, from theperception of socially delivered information to emotional sharing, manifesting themselves across different taxa of increasing biological complexity. We also discuss how social learning is influenced by different factors including pertinence of information for survival, the complexity of the environment, sex, genetic relatedness, and most notably, the relationship between interacting partners. The results appear to form a consistent picture once we shift our focus from emotional contagion as a prerequisite for empathy onto the role of shared emotions in providing vital information about the environment. From this point of view, we can propose approaches that are the most promising for further investigation of complex social phenomena, including learning from others.

Testing the Social Bubble Hypothesis on the Early Dynamics of a Scientific Project: The FET Flagship Candidate FuturICT (2010-2013).

We present an analysis of a large emerging scientific project in the light provided by the social bubbles hypothesis (SBH) that we have introduced in earlier papers. The SBH claims that, during an innovation boom or technological revolution, strong social interactions between enthusiastic supporters weave a network of reinforcing feedbacks that leads to widespread endorsement and extraordinary commitment, beyond what would be rationalized by a standard cost-benefit analysis. By probing the (Future and Emerging Technologies) FET Flagship candidate FuturICT project, as it developed in 2010-2013, we aimed at better understanding how a favorable climate was engineered, allowing the dynamics and risk-taking behaviors to evolve. We document that significant risk-taking was indeed clearly found-especially during workshops and meetings, for instance, in the form of the time allocation of participants, who seemed not to mind their precious time being given to the project and who exhibited many signs of enthusiasm. In this sense, the FuturICT project qualifies as a social bubble in the making when considered at the group level. In contrast, risk-perception at the individual level remained high and not everyone involved shared the exuberance cultivated by the promoters of FuturICT. As a consequence, those not unified under the umbrella of the core vision built niches for themselves that were stimulating enough to stay with the project, but not on a basis of blind over-optimism. Our detailed field study shows that, when considering individuals in isolation, the characteristics associated with a social bubble can vary significantly in the presence of other factors besides exaggerated risk-taking.