When failure is not an option: a police firearms training concept for improving decision-making in shoot/don't shoot scenarios.

Sometimes, policing requires a quick and correct assessment of potentially hazardous situations. The training of tactical gaze control and visual attention, and its positive impact on efficient shoot/don't shoot decisions in police cadets' use of firearms has recently been demonstrated. On this basis, we designed an individual videobased police firearms training that was grounded on the Four-Component Instructional Design Model (4C/ID). We shifted toward an individual blended learning approach where we applied an intervention training focused on situational awareness, tactical gaze control, and visual attention. In a preregistered lab experiment, N = 45 senior police officers were randomly allocated to the intervention training or an active control training that resembled a traditional police firearms training. Both groups watched a self-produced educational video before proceeding to the practical training in our indoor firing range. In a pre- and post-test, they engaged in realistic shoot/don't shoot video scenarios. Both groups did very well regarding decision-making, the optimal muzzle position, and the tactical conduct to keep both eyes open before shooting. Although both groups performed on a comparable level in the pre-test's shoot scenarios, the intervention group significantly improved their response times and time until the first hit. Overall, we were able to provide an adapted, didactically based police firearms training that supplements current standards. We demonstrated that experts are still susceptible to innovative training concepts and therefore substantiate the recommendation to devote more attention to approaches that emphasize the importance of situational awareness, tactical gaze control, and visual attention in police firearms training.

The concept of "Work-Life-Blending": a systematic review.

Work-Life Blending refers to the permeability and dissolution of boundaries between work and personal life, bringing these domains closer together. However, a comprehensive, holistic definition or conceptualisation of Work-Life-Blending is currently lacking. This research aims to address this gap by conducting a systematic literature review to define and clarify the concept. The primary objective is to identify the key factors and dimensions of Work-Life-Blending by reviewing the current state of research, and by offering a clear and precise conceptual framework to guide further research in developing measurable and concrete concepts. We conducted a systematic review following the PRISMA guidelines to achieve this, drawing on keyword-based searches. We searched for English or German manuscripts in the electronic databases Business Source Premier and PsycARTICLES, using keywords such as "blending," "blurring," "fusion," "Entgrenzung," "Verschmelzung," "Vermischung," "boundary," "border," or "demarcation" in combination with "work" and "life." From 1,400 screened references between 2000 and 2023, we identified 302 eligible articles. After applying exclusion criteria, 51 records were retained. Employing a holistic approach, we developed a coding scheme to analyse the articles focusing on antecedents, processes, and outcomes of Work-Life-Blending. Articles were prioritized based on their impact, relevance, and data content. Our analysis revealed a diverse field, and we adopted Clark's central concepts (2000) to categorize Work-Life Blending into four key areas: Domains, Borders, Individual, and Interindividual. Structural analysis allowed us to gain deeper insights into the multifaceted nature of the research field. Diversification was evident in studies exploring various aspects, such as the combination of dimensions (e.g., organizational and individual factors), correlations between factors (e.g., working conditions), and the introduction of new constructs (e.g., motivational processes). Our research addresses a significant knowledge gap in the field of Work-Life-Blending, making valuable contributions to the existing body of knowledge. By examining key categories and proposing an extended definition, this study provides a robust foundation for further investigations. As a result, we established a classification of the determinants. Given the high degree of diversification, we offer a comprehensive framework for future research, contributing to a deeper understanding of Work-Life Blending.

Shoot or Don't Shoot? Tactical Gaze Control and Visual Attention Training Improves Police Cadets' Decision-Making Performance in Live-Fire Scenarios.

Police officers often encounter potentially dangerous situations in which they strongly rely on their ability to identify threats quickly and react accordingly. Previous studies have shown that practical experience and targeted training significantly improve threat detection time and decision-making performance in law enforcement situations. We applied 90-min traditional firearms training as a control condition (35 participants) and a specifically developed intervention training (25 participants) to police cadets. The intervention training contained theoretical and practical training on tactical gaze control, situational awareness, and visual attention, while the control training focused on precision and speed. In a pre- and posttest, we measured decision-making performance as well as (tactical) response preparation and execution to evaluate the training. Concerning cognitive performance training (i.e., decision-making), the number of correct decisions increased from pre- to posttest. In shoot scenarios, correct decisions improved significantly more in the intervention group than in the control group. In don't-shoot scenarios, there were no considerable differences. Concerning the training of response preparation and execution in shoot scenarios, the intervention group's response time (time until participants first shot at an armed attacker), but not hit time, decreased significantly from pre- to posttest. The control group was significantly faster than the intervention group, with their response and hit time remaining constant across pre- and posttest. Concerning the training of tactical action control, the intervention group performed significantly better than the control group. Moreover, the intervention group improved the tactical handling of muzzle position significantly. The results indicate that a single 90-min session of targeted gaze control and visual attention training improves decision-making performance, response time, and tactical handling of muzzle position in shoot scenarios. However, these faster response times do not necessarily translate to faster hit times - presumably due to the motor complexity of hitting an armed attacker with live ammunition. We conclude that theory-based training on tactical gaze control and visual attention has a higher impact on police officers' decision-making performance than traditional firearms training. Therefore, we recommend law enforcement agencies include perception-based shoot/don't-shoot exercises in training and regular tests for officers' annual firearm requalification.

Temporal persistence of after-effects in the n-1 replication task.

In line with the theory of event coding, many studies on tool use show that perceived visual and haptic information interacts with action execution. In two experiments, we investigated the temporal persistence of after-effects within an event file, and after-effects in temporally overlapping event files with the n-1 replication task. Each trial consisted of two phases: In phase 1, participants moved a cursor with a pen on a covered tablet while a gain varied the relation between hand and cursor amplitude (Experiment 1). In phase 2, participants replicated the hand amplitude of phase 1 of the previous trial without visual feedback. Any systematic over- and undershoot would be indicative for after-effects. When the cursor amplitude varied and the hand amplitude remained constant, we did not find any after-effects but adjustment of the internal model. For varying hand amplitudes, after-effects appeared in terms of a contrast and assimilation effect between temporally overlapping event files and within an event file, respectively. In Experiment 2, we confirmed that the observed pattern of over- and undershoots fully reflect assimilation/contrast due to perception-action interaction. The findings extend the current view on the temporal stability of short-term binding in sensorimotor transformation tasks: In the n-1 replication task, after-effects appeared only in trials with varying hand amplitudes. We replicated the contrast effect and assimilation effect, and the assimilation effect persisted for up to approximately 20 s.

Visual target distance, but not visual cursor path length produces shifts in motor behavior.

When using tools effects in body space and distant space often do not correspond. Findings so far demonstrated that in this case visual feedback has more impact on action control than proprioceptive feedback. The present study varies the dimensional overlap between visual and proprioceptive action effects and investigates its impact on aftereffects in motor responses. In two experiments participants perform linear hand movements on a covered digitizer tablet to produce ∩-shaped cursor trajectories on the display. The shape of hand motion and cursor motion (linear vs. curved) is dissimilar and therefore does not overlap. In one condition the length of hand amplitude and visual target distance is similar and constant while the length of the cursor path is dissimilar and varies. In another condition the length of the hand amplitude varies while the lengths of visual target distance (similar or dissimilar) and cursor path (dissimilar) are constant. First, we found that aftereffects depended on the relation between hand path length and visual target distance, and not on the relation between hand and cursor path length. Second, increasing contextual interference did not reveal larger aftereffects. Finally, data exploration demonstrated a considerable benefit from gain repetitions across trials when compared to gain switches. In conclusion, dimensional overlap between visual and proprioceptive action effects modulates human information processing in visually controlled actions. However, adjustment of the internal model seems to occur very fast for this kind of simple linear transformation, so that the impact of prior visual feedback is fleeting.

Intra- and intermodal integration of discrepant visual and proprioceptive action effects.

Integration of discrepant visual and proprioceptive action effects puts high demands on the human information processing system. The present study aimed to examine the integration mechanisms for the motor (Exp. 1) and visual modality (Exp. 2). According to theories of common coding, we assumed that visual as well as proprioceptive information is represented within the same cognitive domain and is therefore likely to affect each other (multisensory cross talk). Thus, apart from the often-confirmed visual dominance in multisensory integration, we asked about intra- and intermodal recall of either proprioceptive or visual information and whether there were any differences between the motor and visual modality. In a replication paradigm, we perturbed the relation between hand movements and cursor movements. The task required the (intra- vs. intermodal) replication of an initially performed (seen) hand (cursor) movement in a subsequent motor (visual) replication phase. First, mechanisms of integration were found to be dependent on the output modality. Visual action effects interfered the motor modality, but proprioceptive action effects did not have any effects on the visual modality. Second, however, intermodal integration was more susceptible to interference, and this was found to be independent from the output modality. Third, for the motor modality, the locus of perturbation (perturbation of cursor amplitude or perturbation of hand amplitude) was irrelevant, but for the visual modality, perturbation of hand amplitudes reduced the cross talk. Tool use is one field of application of these kinds of results, since the optimized integration of conflicting action effects is a precondition for using tools successfully.

Plasticity of verbal fluency in older adults: a 90-minute telephone-based intervention.

BACKGROUND: There is evidence for specific age-related deficits in tasks of verbal fluency. OBJECTIVE: The aim of the present study was to evaluate training and transfer effects after 3 weeks of telephone-based verbal fluency training in old age. METHODS: Participants were assigned to one of three training groups, an active control group, or a no-contact control group. Training consisted of 15 sessions of 6 min each over a period of 3 weeks. For the training tasks, different versions of the verbal fluency task were used, each targeting a specific underlying cognitive process (i.e., processing speed, shifting, or inhibition). To measure transfer effects, a neuropsychological test battery including digit symbol substitution, trail making, go/no-go, digit span, n-back, and a verbal learning and memory test was administered before and after training. RESULTS: Our findings revealed training gains for initial letter fluency training and phonemic switching training, but not for excluded letter fluency training. Moreover, after initial letter fluency training and phonemic switching training, transfer to other verbal fluency tasks was found. In addition, phonemic switching training led to improvement in an untrained short-term memory task. CONCLUSION: The findings demonstrate that a telephone-based cognitive intervention of overall 90 min significantly improved cognitive performance in healthy older adults above and beyond the improvements in the active control group. The findings provide the basis for cognitive interventions that could easily be integrated into everyday lifestyles and are still targeting specific cognitive functions.

Sleep quality and cognitive function in healthy old age: the moderating role of subclinical depression.

OBJECTIVE: Previous research has yielded inconclusive results on the relationship between self-reported sleep quality and cognitive performance in healthy old age. Discrepant findings have been reported regarding processing speed and attention, executive functions, and episodic memory. However, sleep quality has also been found to be related to cognitive performance in patients with depression. Our aim was to clarify the relationship between sleep quality and cognitive performance in healthy older adults, and to evaluate the moderating role of subclinical depression on this relationship. METHOD: The Pittsburgh Sleep Quality Index was used to assess subjective sleep quality in 107 participants (age ≥ 61 years). A broad battery of neuropsychological tests measured basic cognitive processes, executive functions, and memory processes. RESULTS: Subclinical depression moderated the link between sleep quality and cognitive performance. More precisely, poorer sleep quality was associated with lower performance in reasoning, semantic fluency, and shifting in those with high versus low levels of subclinical depression. CONCLUSION: Our findings suggest that poor sleep quality might affect higher order cognitive processes, particularly in those reporting higher levels of subclinical depression. Findings on the relationships between sleep quality, cognitive functioning, and depressive symptomatology are discussed in relation to neurobehavioral theories of sleep.

Perceiving One's Own Limb Movements with Conflicting Sensory Feedback: The Role of Mode of Movement Control and Age.

Previous studies have demonstrated a great uncertainty in evaluating one's own voluntary actions when visual feedback is suspended. We now compare these limitations in younger and older adults during active or passive limb movements. Participants put their dominant hand on a robot arm and performed movements actively or the relaxed limb was moved passively. Either a distorted visual feedback or no visual feedback at all was provided during the movement. Perception of limb movements was attenuated through visual feedback. This effect was more pronounced in older adults. However, no difference between active and passive movements was found. The results provide evidence for the limited awareness of body effects, even in the absence of voluntary actions.

Mirrored visual feedback limits distal effect anticipation.

Modern tools in technological environments are often characterized by a spatial separation of hand actions (operating a remote control) and their intended action effects (displayed movements of an unmanned vehicle, a robot, or an avatar on a screen). Often non-corresponding proximal and distal movement effects put high demands on the human information processing system. The present study aimed to investigate how modern technological environments influence processes of planning and controlling actions. Participants performed ipsi- or contralateral movements in response to colored stimuli, while the stimulus location had to be ignored. They did not see the stimuli and hands directly, but received visual feedback (with retained or reversed spatial relations) on a projection screen in front of them. Visual feedback retaining spatial relations led to the usual Simon effect. However, visual feedback reversing spatial relations inverted the Simon effect in ipsilateral responses, and eliminated it in contralateral responses (Exp. 1). Impairing the proximal movement-effect loop so that proprioceptive/tactile information from the moving hand was no longer a reliable source for planning and controlling actions attenuated compatibility effects (Exp. 2). Moreover, distal action effects predominated action control even for opposing body-related effects. It seemed that action control of transformed movements depended on the reliability of proprioceptive/tactile and visual information. When the amount of feature overlap between proprioception and vision was low and proprioceptive (visual) information was no longer reliable, then distal (proximal) action effects stepped forward and became crucial in controlling transformed actions.

Plasticity of prospective memory through a familiarization intervention in old adults.

Younger adults consistently outperform older adults in laboratory prospective memory tasks. This study examines the effectiveness of an intervention that familiarizes older adults with the sequence of ongoing events to compensate their reduced prospective memory performance. We compared performance and electrophysiological measures of an intervention group (N = 20, 69-83 years) receiving a familiarization intervention to an individually matched control group (N = 20). As ongoing activity a 2-back working memory task was administered. Neural correlates were studied using event related potentials (ERPs) and source localization (standardized low-resolution brain electromagnetic tomography). Behavioural data showed faster reaction times in correct prospective trials and fewer prospective false alarms in the familiarization intervention group. ERP analyses displayed differential patterns for the two groups and source localization measures distinctively presented group differences in prospective memory trials with the control group recruiting more resources for a successful prospective memory performance. Together our data support the hypothesis that the familiarity with the sequence of ongoing events increases prospective memory performance and that this might be based on a higher efficiency of attentional monitoring resources and evaluation processes in the intervention group.

Age effects on controlling tools with sensorimotor transformations.

Controlling tools in technical environments bears a lot of challenges for the human information processing system, as locations of tool manipulation and effect appearance are spatially separated, and distal action effects are often not generated in a 1:1 manner. In this study we investigated the susceptibility of older adults to distal action effects. Younger and older participants performed a Fitts' task on a digitizer tablet without seeing their hand and the tablet directly. Visual feedback was presented on a display in that way, that cursor amplitude and visual target size varied while the pre-determined hand amplitude remained constant. In accordance with distal action effects being predominant in controlling tool actions we found an increase in hand movement times and perceptual errors as a function of visual task characteristics. Middle-aged adults more intensely relied on visual feedback than younger adults. Age-related differences in speed-accuracy trade-off are not likely to account for this finding. However, it is well known that proprioceptive acuity declines with age. This might be one reason for middle-aged adults to stronger rely on the visual information instead of the proprioceptive information. Consequently, design and application of tools for elderly should account for this.

Action control while seeing mirror images of one's own movements: effects of perspective on spatial compatibility.

It is examined whether and how the perspective of seeing one's own movements exerted an influence on action control. Such change in the perspective challenges an information processor, as she or he has to handle successfully the discrepancies between the tactile/proprioceptive feedback and the visual feedback on a projection screen. In the experiments participants responded to visual stimuli, but saw their responses either from the top or with an x-axis reflection, a y-axis reflection, or a reflection about both axes. The results showed that a change in perspective did not impair performance as long as the left-right relations corresponded with the body space (e.g., with visual feedback reflected about the x-axis). By contrast, performance was drastically reduced when visual feedback was reflected about the y-axis or about both axes, so that performed left-side (right-side) movements were seen as right-side (left-side) movements. It is concluded that an actor preferably relies on the information of the visual system, but refers to the tactile/proprioceptive information when it facilitates the task demands.

Perceiving one's own movements when using a tool.

The present study examined what participants perceive of their hand movements when using a tool. In the experiments different gains for either the x-axis or the y-axis perturbed the relation between hand movements on a digitizer tablet and cursor movements on a display. As a consequence of the perturbation participants drew circles on the display while their covered hand movements followed either vertical or horizontal ellipses on the digitizer tablet. When asked to evaluate their hand movements, participants were extremely uncertain about their trajectories. By varying the amount of visual feedback, findings indicated that the low awareness of one's own movements originated mainly from an insufficient quality of the humans' tactile and proprioceptive system or from an insufficient spatial reconstruction of this information in memory.

Interacting with notebook input devices: an analysis of motor performance and users' expertise.

In the present study the usability of two different types of notebook input devices was examined. The independent variables were input device (touchpad vs. mini-joystick) and user expertise (expert vs. novice state). There were 30 participants, of whom 15 were touchpad experts and the other 15 were mini-joystick experts. The experimental tasks were a point-click task (Experiment 1) and a point-drag-drop task (Experiment 2). Dependent variables were the time and accuracy of cursor control. To assess carryover effects, we had the participants complete both experiments, using not only the input device for which they were experts but also the device for which they were novices. Results showed the touchpad performance to be clearly superior to mini-joystick performance. Overall, experts showed better performance than did novices. The significant interaction of input device and expertise showed that the use of an unknown device is difficult, but only for touchpad experts, who were remarkably slower and less accurate when using a mini-joystick. Actual and potential applications of this research include an evaluation of current notebook input devices. The outcomes allow ergonomic guidelines to be derived for optimized usage and design of the mini-joystick and touchpad devices.