Doctor of Philosophy / Department of Psychology / Lester C. Loschky / Öhman and Mineka (2001) proposed the existence of an evolved fear module with four Fodorian characteristics of modularity. They presented evidence that the fear module is selective, automatic, encapsulated, and operates in dedicated subcortical neural circuitry. The consistently rapid physiological and behavioral (attention capture) evidence (e.g., Öhman & Mineka, 2001) provides clear support for its automaticity. However, recent developments (e.g., Blanchette, 2006) cast doubt on the selectivity of the module. Specifically, it is unclear whether or not the fear module automatically responds selectively to evolutionarily ancient fear stimuli or whether modern threats may also elicit automatic responding. Furthermore, previous research using visual search paradigms has produced unclear results regarding the evolutionarily derived selectivity of the fear module. Unfortunately, the visual search method is notoriously sensitive to visual characteristics of stimuli (Duncan & Humphreys, 1989). However, eye movements provide a valid alternative measure of covert attention capture. In order to clarify the issues, Experiment 1 used an oculomotor inhibition paradigm to present ancient and modern threats with one another or neutral stimuli in competition for visual attention. In addition, we collected measures of participants’ experience with the stimuli to assess the influence of experience/familiarity/learning on rapid attention to threats. Furthermore, because image inversion maintains low level stimulus characteristics (e.g., spatial frequencies, contrast, and luminance) while disrupting the semantic processing of images, presenting the stimulus pairs upside down was used to determine whether any observed effects were due to low level stimulus characteristics. Experiment 1 produced null results with respect to systematic differences in attentional processes as a function of threat type. Because Experiment 1 was modeled after Nummenmaa et al., (2009, Exp 3), it was therefore necessary to attempt to replicate their findings. Experiment 2 successfully replicated the findings of Nummenmaa et al. Therefore, it is suggested that the rapid attention processes responsible for systematic deviations in saccade trajectories seen in Experiment 2 (and Nummenmaa et al., 2009, Exp 3) do not translate to the methodology used in Experiment 1. Given the findings from the present study, the question of whether or not there exists and evolved fear module remains open. This study clearly supports the existence of an attentional bias for emotional content as indicated through the use of oculomotor inhibition paradigm. However, like the visual search methodology, the oculomotor inhibition paradigm appears to be very sensitive to visual differences of the stimuli.

Previous psychological research has demonstrated the benefits of visiting natural environments, especially coastal areas. However, research within Marine Biology has shown that such visits can harm natural habitats. Consequently, this thesis uses an integrative approach to examine both the risks to the environment and benefits to the human visitors in the context of rocky shores (intertidal areas where solid rock predominates). This was investigated using seven studies that involved a range of methods. Perception-based surveys (Studies 1 & 2) explored the perceived impacts on the visitor, and the potential impacts these visits can have on the rocky shore. Study 3 then examined the impacts on visitors’ well-being & marine awareness directly using a before-after survey on current visitors to two rocky shores. The most prominent habitat threat (leaving rubbish) was then examined in greater detail. Studies 4 and 5 examined the effects of marine litter on individuals’ well-being using two laboratory experimental designs; comparing individuals’ quantitative (Study 4) and qualitative (Study 5) responses to natural and littered shores. The final two studies then focused on an activity that reduces marine litter: Study 6 adopted a pre-post design to examine the benefits of engaging in beach cleans for current volunteers, whilst Study 7 used an experimental design comparing beach cleans with two other coastal activities on a more naïve sample. Overall, these studies provide evidence that experiencing rocky shores are beneficial for well-being and marine awareness. Counteracting such benefits, litter left behind after recreational visits were found to be detrimental to individuals’ well-being. As one potential solution to this issue, beach cleans were found to have the same, and additional beneficial effects on the individual as other coastal activities. Thus, activities which have a relatively positive impact on the environment can also have similar if not additional benefits to the visitor. This programme of research shows the importance of taking a holistic, integrative approach that takes into account both the risks to the environment and benefits to the individual resulting from recreational visits to natural environments.

Effective use of Machine Learning to support extracting maximal information from limited sensor data is one of the important research challenges in robotic sensing. This thesis develops techniques for detecting and characterizing patterns in noisy sensor data. Our Bayesian Aggregation (BA) algorithmic framework can leverage data fusion from multiple low Signal-To-Noise Ratio (SNR) sensor observations to boost the capability to detect and characterize the properties of a signal generating source or process of interest. We illustrate our research with application to the nuclear threat detection domain. Developed algorithms are applied to the problem of processing the large amounts of gamma ray spectroscopy data that can be produced in real-time by mobile radiation sensors. The thesis experimentally shows BA’s capability to boost sensor performance in detecting radiation sources of interest, even if the source is faint, partiallyoccluded, or enveloped in the noisy and variable radiation background characteristic of urban scenes. In addition, BA provides simultaneous inference of source parameters such as the source intensity or source type while detecting it. The thesis demonstrates this capability and also develops techniques to efficiently optimize these parameters over large possible setting spaces. Methods developed in this thesis are demonstrated both in simulation and in a radiation-sensing backpack that applies robotic localization techniques to enable indoor surveillance of radiation sources. The thesis further improves the BA algorithm’s capability to be robust under various detection scenarios. First, we augment BA with appropriate statistical models to improve estimation of signal components in low photon count detection, where the sensor may receive limited photon counts from either source and/or background. Second, we develop methods for online sensor reliability monitoring to create algorithms that are resilient to possible sensor faults in a data pipeline containing one or multiple sensors. Finally, we develop Retrospective BA, a variant of BA that allows reinterpretation of past sensor data in light of new information about percepts. These Retrospective capabilities include the use of Hidden Markov Models in BA to allow automatic correction of a sensor pipeline when sensor malfunction may be occur, an Anomaly- Match search strategy to efficiently optimize source hypotheses, and prototyping of a Multi-Modal Augmented PCA to more flexibly model background and nuisance source fluctuations in a dynamic environment.

Botnets are a pervasive threat to the Internet and its inhabitants. A botnet is a collection of infected machines that receive commands from the botmaster, a person, group or nation- state, to perform malicious actions. Instead of “cleaning” individual infections, one can sever the method of communication between a botmaster and her zombies by attempting a botnet takedown, which contains the botnet and its malicious actions. Unfortunately, takedowns are currently performed without technical rigor nor are there automated and independent means to measure success or assist in performing them. This dissertation focuses on understanding the criminal infrastructure that enables communication between a botmaster and her zombies in order to measure attempts at, and to perform, successful takedowns. We show that by interrogating malware and performing large-scale analysis of passively collected network data, we can measure if a past botnet takedown was successful and use the same techniques to perform more comprehensive takedowns in the future.

The relational identity threat response model describes how workplace relationships experiencing relational identity threat predict discretionary workplace behavior (i.e. momentary organizational voice, momentary behavioral engagement, and momentary supervisor-directed deviance). More specifically, the model utilizes an experience sampling methodology to capture the ebb and flow or momentary changes within supervisor-subordinate relationships with a focus on potential negative shifts in a subordinate’s relational identity with his/her supervisor. By examining momentary behavior, meaning actions subordinates take within a short period of time such as the last few hours, I draw attention to the often overlooked effects of dynamic workplace relationships, arguing that the ebb and flow within supervisor-subordinate interactions play a critical role in subordinate choice as to the amount of momentary organizational voice, momentary behavioral engagement, and momentary supervisor-directed deviance to offer. That is, I utilize recent developments within social identity theory (Brewer & Gardner, 1996; Sluss & Ashforth, 2007) to examine how subordinates reconcile relational identity threat, or potential shifts in the nature of ‘who we are’ (Sluss & Ashforth, 2007). Further, the data support the argument that momentary relational voice, which is communication to the supervisor focused on improving the workplace relationship or relational functioning, partially mediates relational identity threat’s consequences for positive discretionary workplace behavior (i.e. momentary organizational voice, momentary behavioral engagement). Additionally, I draw attention to self-compassion (i.e. how a subordinate treats him or herself [Neff, 2003a]), which moderates subordinate responses to relational identity threat within a supervisor-subordinate relationship.

This dissertation analyzes the effects of Latino immigration on the representation of Latinos and African-Americans on school boards and attempts to explain under what conditions Latino immigrants provoke opposition among whites. I consider two measures of representation based on representative bureaucracy—the membership of Latinos and African-Americans on school boards and bias in the responsiveness of white school board members toward these two groups. Whites as the major racial group in the U.S. have been the subject of much intergroup relations research focusing on competition for scarce resources, perceived threat and group biases (e.g., Evans and Giles, 1986; Giles and Evans, 1985, 1986; Esses, Jackson and Armstrong, 1998), and I also focus on their racial behaviors as voters in school board elections and as school board members. I consider Latino immigration in this research because emerging evidence suggests that Latino immigration poses a growing threat to whites, leading them to shift their support from Latinos to a countervailing group, such as African-Americans (e.g., Meier and Stewart, 1991; Rocha, 2007). It is likely that the reactions of whites to Latino immigration are conditioned by their preexisting racial attitudes, so this dissertation also tests competing theories of community racial climate—group threat and group contact. I expect that racial tensions within a community should moderate the influence of Latino immigration on these two forms of Latino and African-American representation. Overall, this dissertation expands the study of representative bureaucracy by combining past research on community racial climates with conditions influencing minority representation.

Although largely overlooked in much of the previous research on political tolerance, I argue that contextual factors, specifically state-level features, play a significant role in influencing individual tolerance judgments. Drawing from extant theories of public opinion, international conflict, and political institutions, I seek to further our understanding of the determinants of political tolerance by trying to answer the following question: What accounts for the significant differences in political tolerance levels across countries? While models using individual-level predictors account for some of the disparity in tolerance levels, a substantial amount remains unexplained. I assert that several macro-level theoretical frameworks offer compelling explanations for the marked difference in tolerance levels across countries. Specifically, I examine the effect of state-level external threats, internal threats, and the role of domestic political institutions in shaping individual attitudes towards unpopular groups. To test my propositions, I use data from the 1995-1997 World Values survey as well as multi-level statistical modeling to estimate the aggregate effects of state-level factors on political tolerance levels across 33 countries while also controlling for individual-level predictors.This dissertation demonstrates that elevated objective threats to the state, whether international disputes or incidents of civil conflict, serve to dampen overall tolerance levels. In doing so, this study also highlights that not all types of external threat resonateequally amongst the public. Individuals in countries involved in territorial disputes or countries targeted in international disputes are generally less tolerant overall than those in countries involved in disputes over other issues. In terms of domestic political institutions, I find that electoral rules designed to build consensus and ameliorate societal tensions among groups may actually serve to foster intolerance in countries under certain conditions. Finally, my analyses reveal that the effect of democratic longevity on political tolerance levels is actually conditional based on the type of political institutions that exist in a country. Overall, the findings discovered here underscore the importance of contextual factors in shaping political tolerance levels across countries and stresses the need for this type of analysis in future studies of political tolerance.

The purpose of this study was to identify significant relationships betweenidentity threat, relatedness or sense of belongingness, and academic achievement in asample of minority college students who were enrolled in an underrepresented academicfield in higher education. Our sample included 56 Hispanic students enrolled in an Organic Chemistry class at a Southwest University. Findings show that Ethnic Sense ofBelongingness positively predicted Classroom Sense of Belongingness, which in turnpredicted Effort. This relationship was also impacted by students' perceptions of Self-Efficacy to Achieve, Teacher Trust and Academic Support, and Intrinsic Motivation andKnow and Accomplish. Overall, findings highlight the influence of ethnic sense ofbelongingness at school, in achievement and motivational processes in the classroom.

Threats and violence, or the risk of being subjected to threats and violence in the workplace, is a major health and safety problems that exists in many professions. To be exposed to threats and violence can have serious consequences for the employee's health but also for the organization in question. The aims of this study was to investigate the prevalence of threats and violence at the Swedish Migration Board detention, and to examine whether there were health problems among employees who may be exposed to threats and violence. A web-based questionnaire was answered by 29 employees (response rate = 51 percent). The results showed that more employees had been exposed to verbal threats (66 percent), compared to physical violence (10 percent), and they showed a greater tendency to report physical violence, as opposed to verbal threats. The participants indicated that factors such as working alone, convey rejection decisions and escape attempts increased the risk of threats and violence. However, the majority of the participants reported that the preventive work, including, alarms, training and available equipment, worked fine. Further everyone reported that they received good support from colleagues when they were subjected to a threat or violent situation. Generally the employees reported that their health was good, which might partly be related to an experience that the preventions worked well at this workplace. Future research should investigate such a relationship.

According to the transactional theory of stress and coping, threat appraisals influence coping and adjustment. Previous research has shown that threat appraisals mediate relations between violence exposure and adjustment, but few studies have examined links between threat appraisals and coping. The current study examined relations between violence exposure, threat appraisals, and coping among typologies of victimized adolescents. The sample included 159 predominately African American adolescents (M = 12.1). Path analyses were used to test whether threats of negative evaluation by self and others mediated relations between violence exposure and avoidance and positive reframing coping, respectively. Results did not indicate mediation or differential relations between study constructs for victim typologies. Significant direct effects were found between violence exposure and negative self-evaluation and positive reframing, such that greater violence exposure was associated with a greater likelihood of self-blaming and positive reframing. These findings have implications for youth violence prevention and intervention efforts.