Thesis (MA) -- University of Stellenbosch, 2000. / ENGLISH ABSTRACT: Judgement of risk for negative events in certain situations was investigated in a group of emergency medical service (EMS) personnel with a diagnosis of posttraumatic stress disorder (PTSD; n = 27) and a group without PTSD (n = 74). Participants completed the PTSD Symptom Scale: Self-Report version (Faa, Riggs, Dancu, & Rothbaum, 1993), an EMS work experiences questionnaire, the Beck Depression Inventory (Beck, Rush, Shaw, & Emery, 1979), and an event probability questionnaire designed to assess judgement of risk. Participants with PTSD overestimated amount of risk involved in comparison to participants without PTSD, thereby demonstrating a judgement bias for risk related events. The present study found that the judgement bias in PTSD participants extended to include not just external harm related events but also general negative events (without potential threatening/harmful consequences), negative social events, and negative workrelated events. Of the posttraumatic symptomatology assessed, avoidance symptomatology was found to be the best predictor of judgement bias. The results of the present study are discussed in terms of the cognitive clinical psychology theories of PTSD, which predict the manifestation of judgement bias in PTSD, and cognitive experimental psychology explanations of the effect of negative emotional states on judgement processes. / AFRIKAANSE OPSOMMING: Oordeeloor risiko vir negatiewe gebeurtenisse in sekere situasies is ondersoek by "n groep mediese nooddienspersoneel met "n diagnose van posttraumatiese stresversteuring (PTSV; n = 27) en "n groep sonder PTSV (n = 74). Deelnemers het die PTSD Symptom Scale: Self-Report version (Foa, Riggs, Dancu, & Rothbaum, 1993), "n mediese nooddiens werkservaringe-vraelys, die Beck Depression Inventory (Beck, Rush, Shaw, & Emery, 1979), en "n gebeurtenis-waarskynlikheidsvraelys wat opgestel is om oordeeloor risiko te meet, voltooi. Deelnemers met PTSV het die mate van risiko betrokke oorskat in vergelyking met deelnemers sonder PTSVen sodoende "n beoordelingsydigheid vir risiko-verbandhoudende situasies gedemonstreer. In die huidige studie is gevind dat beoordelingsydigheid by PTSV deelnemers nie beperk was tot eksterne skade-verbandhoudende gebeurtenisse nie, maar dat dit ook veralgemeen het na algemene negatiewe gebeurtenisse (sonder potensieel skadelike gevolge), negatiewe sosiale gebeurtenisse, en negatiewe werksverwante gebeurtenisse. Daar is gevind dat, wat PTSV-simptomatologie betref, vermyding die beste voorspeller van beoordelingsydigheid was. Die resultate van die huidige studie word bespreek in terme van kognitiewe klinies-sielkundige teorieë van PTSV, wat die aanwesigheid van beoordelingsydigheid voorspel, en kognitiewe eksperimentele-sielkunde verklarings van die effek van negatiewe emosionele toestande op beoordelingsprosesse.

Within the evolutionary framework of sexual selection and parental investment theory, the study employed four experiments to examine the effects of mating and parenting awareness on the perception and assessment of high risk sports. In Study 1, participants were exposed, in random order, five types of pictures---attractive female, regular female, attractive male, regular male, and award winning pictures. After the activation of each of these pictures, participants were asked to respond to pictures depicting high risk sport events. The reaction time to high risk sport events was shortest when men saw attractive female pictures. The same effect was not found in female participants viewing attractive male pictures. Study 2 used the same mating awareness manipulation (attractive female pictures versus other pictures) but also added parenting and child rearing pictures depicting pregnant women or young children with their mothers. The results showed that men's reaction time to high risk sports was shorter when exposed to attractive female pictures than other conditions and was longer when exposed to parenting-related pictures. Study 3 included socialsexual orientation as a covariate and results similar to Study 1 were obtained after controlling for the extraneous influence of socialsexual orientation. Study 4 focused on risk assessment in different domains including entertainment, financial investment, health and social risk. The results showed that men under-assessed risk in the entertainment domain when exposed to attractive female pictures than to award winning pictures. However, the same effect was not found with other risk domains. Overall, the findings support the evolutionary account of risk taking which is sexually selected male attribute as an ornament to attract mating partners and which is reduced when men shift from mating to parenting and child rearing concerns. One practical implication for controlling risk taking behaviors among adolescents is the knowledge that risk taking behavior may be more likely in mixed- than in single-gender social groups. / 李宏利. / Adviser: Lei Chang. / Source: Dissertation Abstracts International, Volume: 70-06, Section: A, page: 1923. / Thesis (doctoral)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (p. 93-118). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in Chinese and English. / School code: 1307. / Li Hongli.