| 1. |
- Bertilsson, Johan, et al.
(författare)
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Stress Levels Escalate When Repeatedly Performing Tasks Involving Threats
- 2019
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Ingår i: Frontiers in Psychology. - : Frontiers Media SA. - 1664-1078. ; 10, s. 1562-1562
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Tidskriftsartikel (refereegranskat)abstract
- Police work may include performing repeated tasks under the influence of psychological stress, which can affect perceptual, cognitive and motor performance. However, it is largely unknown how repeatedly performing stressful tasks physically affect police officers in terms of heart rate and pupil diameter properties. Psychological stress is commonly assessed by monitoring the changes in these biomarkers. Heart rate and pupil diameter was measured in 12 male police officers when performing a sequence of four stressful tasks, each lasting between 20 and 130 s. The participants were first placed in a dimly illuminated anteroom before allowed to enter a brightly lit room where a scenario was played out. After each task was performed, the participants returned to the anteroom for about 30 s before performing the next sequential task. Performing a repeated sequence of stressful tasks caused a significant increase in heart rate (p = 0.005). The heart rate started to increase already before entering the scenario room and was significantly larger just after starting the task than just before starting the task (p < 0.001). This pattern was more marked during the first tasks (p < 0.001). Issuance of a verbal "abort" command which terminated the tasks led to a significant increase of heart rate (p = 0.002), especially when performing the first tasks (p = 0.002). The pupil diameter changed significantly during the repeated tasks during all phases but in a complex pattern where the pupil diameter reached a minimum during task 2 followed by an increase during tasks 3 and 4 (p ≤ 0.020). During the initial tasks, the pupil size (p = 0.014) increased significantly. The results suggest that being repeatedly exposed to stressful tasks can produce in itself an escalation of psychological stress, this even prior to being exposed to the task. However, the characteristics of both the heart rate and pupil diameter were complex, thus, the findings highlight the importance of studying the effects and dynamics of different stress-generating factors. Monitoring heart rate was found useful to screen for stress responses, and thus, to be a vehicle for indication if and when rotation of deployed personnel is necessary to avoid sustained high stress exposures.
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| 2. |
- Bertilsson, Johan, et al.
(författare)
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Towards systematic and objective evaluation of police officer performance in stressful situations
- 2020
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Ingår i: Police Practice and Research. - : Informa UK Limited. - 1561-4263 .- 1477-271X. ; 21:6, s. 655-669
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Tidskriftsartikel (refereegranskat)abstract
- To ensure a continuous high standard of police units, it is critical to recruit people who perform well in stressful situations. Today, this selection process includes performing a large series of tests, which still may not objectively reveal a person’s capacity to handle a life-threatening situation when subjected to high levels of stress. To obtain more systematic and objective data, 12 police officers were exposed to six scenarios with varying levels of threat while their heart rate and pupil size were monitored. The scenarios were filmed and six expert evaluators assessed the performance of the police officers according to seven predefined criteria. Four of the scenarios included addressing a moderate threat level task and the scenarios were executed in a rapid sequence. Two further scenarios included a familiar firearm drill performed during high and low threat situations. The results showed that there was a large agreement between the experts in how they judged the performance of the police officers (p < 0.001). Performance increased significantly over tasks in four of the seven evaluation criteria (p ≤ 0.037). There was also a significant effect of pupil size (p = 0.004), but not heart rate, when comparing the different sequential scenarios. Moreover, a high level of threat considerably impaired the motor performance of the police officers during the firearms drill (p = 0.002). Finally, the pupil seemed to systematically dilate more when a threat appeared immediately than with a delay in the scenarios (p = 0.007). We conclude that systematic and quantitative judgments from experts provide valuable and reliable information about the performance of participants in realistic and stressful policing scenarios. Furthermore, objective physiological measures of heart rate and pupil size may help to explain and understand why performance sometimes deteriorates.
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| 3. |
- Dahl, Mats, et al.
(författare)
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Analysis of eyewitness testimony in a police shooting with fatal outcome - Manifestations of spatial and temporal distortions
- 2018
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Ingår i: Cogent Psychology. - : Taylor & Francis. - 2331-1908. ; 5:1
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Tidskriftsartikel (refereegranskat)abstract
- Eyewitness statements are commonly used in the criminal justice system and viewed as having a high-probative value, especially when the witness has no motive to lie, other witness recollection corroborates the account, orthe witness is highly confident. A fatal police shooting incident in Sweden had 13 witnesses (nine civilians and four police officers) and was also filmed with two mobile phones. All interviews were conducted before witnesses viewed the films, allowing for the analysis of discrepancies between their statements and the videos. In this incident, a police patrol was sent to find out a man who was reported to have attacked two persons with a knife. When found, the perpetrator refused to obey the officer's commands, and the police eventually shot at him. The analysis showed clear differences between the witness testimonies and the film. Elements associated with perceived threat, for example, the assailant's armament and movement direction and number of shots fired, were remembered fairly accurately. However, most witnesses poorly recollected when, that is, after which shot, the assailant fell to the ground. Moreover, memory of the actual order of events was altered and important aspects omitted that were crucial from a legal point of view.
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| 4. |
- Ek, Simon
(författare)
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Structural Change, Match Quality, and Integration in the Labor Market
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Essay I: Are workers with poor outside opportunities less responsive and more susceptible to negative demand shifts in routine occupations? To answer this, I create and estimate an occupation specialization index (OSI) using Swedish register data and machine learning tools. It measures the expected difference in utility between a worker's occupation and his best non-routine outside option. This determines the loss he is willing to tolerate to avoid switching. Low-OSI employees disproportionately left routine work. Their future wage growth was akin to comparable workers initially in non-routine occupations. By contrast, routine specialists largely stayed put and experienced lower wage growth than generalists and non-routine specialists. Essay II (with Adrian Adermon, Georg Graetz, and Yaroslav Yakymovych): Using a new identification strategy, we jointly estimate the growth in occupational wage premia and time-varying occupation-specific life-cycle profiles for Swedish workers 1996–2013. We document a substantial increase in between-occupation wage inequality due to differential growth in premia. The association of wage premium growth and employment growth is positive, suggesting that premium growth is predominantly driven by demand side factors. Essay III (with Peter Fredriksson, Lena Hensvik, and Oskar Nordström Skans): We provide two pieces of evidence that workers' capacity to extract rents from match-specific productivity hinges on their outside options. Using a measure of match quality, derived from the relationship between workers' multidimensional skills and job-specific skill requirements, we show that: (i) wages within ongoing matches are more closely aligned with match quality following an improvement of local labor market conditions; (ii) wages of job-to-job movers are positively related to the match quality in the previous job, even when controlling for previous wage.Essay IV (with Mats Hammarstedt, and Per Skedinger): In a field experiment we study the causal effects of previous work experience and language skills when Syrian refugees in Sweden apply for low-skilled jobs. We find no evidence of sizeable effects from experience or completed language classes on the probability of receiving callback from employers. However, female applicants were more likely than males to receive a positive response. As a complement to the experiment, we interview a select number of employers.
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| 5. |
- Gullberg, Mats, et al.
(författare)
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Cytokine detection by antibody-based proximity ligation
- 2004
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 101:22, s. 8420-4
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Efficient and precise detection techniques, along with extensive repertoires of specific binding reagents, will be needed to meet the challenges of proteome analyses. The recently established proximity ligation mechanism enables sensitive high-capacity protein measurements by converting the detection of specific proteins to the analysis of DNA sequences. Proximity probes containing oligonucleotide extensions are designed to bind pairwise to target proteins and to form amplifiable tag sequences by ligation when brought in proximity. In our previous report, both the ligatable arms and the protein binders were DNA molecules. We now generalize the method by providing simple and convenient protocols to convert any polyclonal antibodies or matched pair of monoclonal antibodies to proximity probe sets through the attachment of oligonucleotide sequences. Sufficient reagent for >100,000 proximity ligation assays can be prepared from 1 microg of antibody. The technique is applied to measure cytokines in a homogenous test format with femtomolar detection sensitivities in 1-microl samples, and we exemplify its utility in situations when only minute sample amounts are available.
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