| 11. |
- Dahlman, Joakim, 1974-, et al.
(författare)
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Could sound be used as a strategy for reducing symptoms of perceived motion sickness?
- 2008
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Ingår i: Journal of NeuroEngineering and Rehabilitation. - : Springer Science and Business Media LLC. - 1743-0003. ; 5:35
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Tidskriftsartikel (refereegranskat)abstract
- Background: Working while exposed to motions, physically and psychologically affects a person. Traditionally, motion sickness symptom reduction has implied use of medication, which can lead to detrimental effects on performance. Non-pharmaceutical strategies, in turn, often require cognitive and perceptual attention. Hence, for people working in high demand environments where it is impossible to reallocate focus of attention, other strategies are called upon. The aim of the study was to investigate possible impact of a mitigation strategy on perceived motion sickness and psychophysiological responses, based on an artificial sound horizon compared with a non-positioned sound source.Method: Twenty-three healthy subjects were seated on a motion platform in an artificial sound horizon or in non-positioned sound, in random order with one week interval between the trials. Perceived motion sickness (Mal), maximum duration of exposure (ST), skin conductance, blood volume pulse, temperature, respiration rate, eye movements and heart rate were measured continuously throughout the trials.Results: Mal scores increased over time in both sound conditions, but the artificial sound horizon, applied as a mitigation strategy for perceived motion sickness, showed no significant effect on Mal scores or ST. The number of fixations increased with time in the non-positioned sound condition. Moreover, fixation time was longer in the nonpositioned sound condition compared with sound horizon, indicating that the subjects used more time to fixate and, hence, assumingly made fewer saccades.Conclusion: A subliminally presented artificial sound horizon did not significantly affect perceived motion sickness, psychophysiological variables or the time the subjects endured the motion sickness triggering stimuli. The number of fixations and fixation times increased over time in the non-positioned sound condition.
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| 12. |
- Dahlman, Joakim, 1974-, et al.
(författare)
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Effects of Motion Sickness on Encoding and Retrieval
- 2010
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Tidskriftsartikel (refereegranskat)abstract
- Objective: In this study, possible effects of motion sickness on encoding and retrieval of words were investigated. Background: The impact of motion sickness on human performance has been studied with regards to psychomotor functions and over learned skills, as well as to novel situations requiring encoding and retrieval skills through the use of short term memory. In this study, possible effects of motion sickness on encoding and retrieval of words were investigated. Method: Forty healthy participants, half of them males, performed a continuous recognition task (CRT) during exposure to a motion sickness triggering optokinetic drum. The CRT was employed as a measurement of performance and consisted of encoding and retrieval of words. The task consisted of three consecutive phases 1) encoding of familiar words; 2) encoding and retrieval of words under the influence of motion sickness; 3) retrieval of words after exposure. Results: Data analysis revealed no significant differences in the ability to encode or retrieve words during motion sickness compared with a control condition. In addition, there were no significant correlations between the level of motion sickness and performance of the CRT. Conclusion: The results indicate that encoding and retrieval of words are not affected by moderate levels of motion sickness. Application: This research has implications for operational settings where professionals experience moderate levels of motion sickness.
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| 13. |
- Dahlman, Joakim, 1974-, et al.
(författare)
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Performance and Autonomic Responses during Motion Sickness
- 2009
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Ingår i: Human Factors. - : SAGE Publications. - 0018-7208 .- 1547-8181. ; 51:1, s. 56-66
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The aim of the study was to investigate how motion sickness, triggered by an optokinetic drum, affects short term memory performance and to explore autonomic responses to perceived motion sickness. Background: Previous research has found motion sickness to decrease performance, but it is not known how short term memory in particular is affected. Method: Thirty-eight healthy participants performed a listening span test while seated in a rotating optokinetic drum. Measurements of motion sickness, performance, heart rate, skin conductance, blood volume pulse, and pupil size were performed simultaneously throughout the experiment. Results: A total of 16 participants terminated the trial due to severe nausea, while the other 22 endured the full 25 minutes. Perceived motion sickness increased over time in both groups, but less among those who endured the trial. Short term memory performance decreased towards the end for those who terminated, while it increased for the other group. Results from the measured autonomic responses were ambiguous. Conclusion: The present study concludes that performance, measured as short term memory, declines as perceived motion sickness progresses. Application: This research has potential implications for command and control personnel in risk of developing motion sickness.
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| 14. |
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| 15. |
- Dahlman, Joakim, 1974-
(författare)
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Psychophysiological and Performance Aspects on Motion Sickness
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Motion sickness is not an illness, but rather a natural autonomic response to an unfamiliar or specific stimulus. The bodily responses to motion sickness are highly individual and contextually dependent, making them difficult to predict. The initial autonomic responses are similar to the ones demonstrated when under stress. When under the influence of motion sickness, motivation and ability to perform tasks or duties are limited. However, little is known about how specific cognitive functions are affected. Furthermore, standard mitigation strategies involve medications that induce fatigue or strategies that require cognitive capabilities. Both of them may result in reduced capability to perform assigned tasks or duties. Hence, there is a need for alternative mitigation strategies.The aim of the thesis was to study psychophysiological and performance aspects on motion sickness. The long-term goal is to provide strategies for mitigation and prevention of motion sickness by identifying psychophysiological responses as predictors for both wellbeing and performance. This thesis comprises four studies, in which 91 participants were exposed to two different motion sickness stimuli, either an optokinetic drum or a motion platform. Before the tests, a method for extracting fixations from eye-tracking data was developed as a prerequisite for studying fixations as a possible mitigation strategy for reducing motion sickness. During exposure to stimuli that triggers motion sickness, performance was studied by testing short-term memory and encoding and retrieval. In the final study, the effects of an artificial sound horizon were studied with respect to its potential to subconsciously function as a mitigating source.The results of the measurements of the psychophysiological responses were in accordance with previous research, confirming the ambiguity and high individuality of the responses as well as their contextual dependencies. To study fixations, a centroid mode algorithm proved to be the best way to generate fixations from eye-movement data. In the final study, the effects of the sound horizon were compared to the effects of a non-positioned sound. In the latter condition, both fixation time and the number of fixations increased over time, whereas none of them showed a significant time effect in the sound horizon condition. The fixation time slope was significantly larger in the non-positioned sound condition compared to the sound horizon condition. Number of fixations, heart rate, and skin conductance correlated positively with subjective statements that referred to motion sickness. Among participants that were susceptible to motion sickness symptoms, short-term memory performance was negatively affected. However, no effects of motion sickness on encoding and retrieval were found, regardless of susceptibility.Future studies should continue focusing on autonomic responses and psychological issues of motion sickness. Factors such as motivation, expectancies, and previous experiences play a major and yet relatively unknown role within the motion sickness phenomena.
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| 16. |
- D’Arcy, Emily, et al.
(författare)
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Get it right, make it easy, see it all : Viewpoints of autistic individuals and parents of autistic individuals about the autism diagnostic process in Australia
- 2021
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Ingår i: Research in Autism Spectrum Disorders. - : Elsevier. - 1750-9467 .- 1878-0237. ; 85
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Tidskriftsartikel (refereegranskat)abstract
- Background: The clinical process for being evaluated for an autism diagnosis is often time consuming and stressful for individuals and their caregivers. While experience of and satisfaction with the diagnostic process has been reviewed in the literature, few studies have directly investigated the viewpoints of individuals diagnosed with autism and caregivers of autistic individuals about what is important in the autism diagnostic process.Method: A Q methodological design was employed to capture the subjective viewpoints about the diagnostic process of individuals on the autism spectrum and caregivers of autistic individuals. Thirty-eight participants responded to a set of 66 statements representing different aspects of the autism diagnostic process.Results: The analysis identified three significant viewpoints: Get it Right, Make it Easy, and See it All. Participants reflected upon the importance of a comprehensive diagnostic assessment process, ease of diagnostic processes, and a holistic approach to autism diagnosis for autistic individuals and caregivers of autistic individuals.Conclusions: The findings provide a consumer perspective that encourages reform of the current process for diagnosing autism in Australia, and an insight into what consumers are wanting from diagnostic services. This information is useful for policy-makers and service providers to create a more supportive and client-centred diagnostic process at all levels of service delivery.
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| 17. |
- Earl, Robyn, et al.
(författare)
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Viewpoints of pedestrians with and without cognitive impairment on shared zones and zebra crossings
- 2018
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Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 13:9
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundShared zones are characterised by an absence of traditional markers that segregate the road and footpath. Negotiation of a shared zone relies on an individual’s ability to perceive, assess and respond to environmental cues. This ability may be impacted by impairments in cognitive processing, which may lead to individuals experiencing increased anxiety when negotiating a shared zone.MethodQ method was used in order to identify and explore the viewpoints of pedestrians, with and without cognitive impairments as they pertain to shared zones.ResultsTwo viewpoints were revealed. Viewpoint one was defined by “confident users” while viewpoint two was defined by users who “know what [they] are doing but drivers might not”.DiscussionOverall, participants in the study would not avoid shared zones. Pedestrians with intellectual disability were, however, not well represented by either viewpoint, suggesting that shared zones may pose a potential barrier to participation for this group.
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| 18. |
- Earl, Robyn, et al.
(författare)
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Visual search strategies in a shared zone in pedestrians with and without intellectual disability
- 2019
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Ingår i: Research in Developmental Disabilities. - : Elsevier. - 0891-4222 .- 1873-3379. ; 94
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Tidskriftsartikel (refereegranskat)abstract
- People with intellectual disability (ID) may find shared zones troublesome to negotiate because of the lack of the traditional clearly defined rules and boundaries. With the built environment identified as a barrier to active travel and community access, it is vital to explore how pedestrians with ID navigate shared zones to ensure that this group is not placed in harm's way or discouraged from active travel because of the implications of shared zones. This study investigated the visual strategies of 19 adults with ID and 21 controls who wore head mounted eye trackers in a Shared Zone and at a zebra crossing (as a contrast traffic environment). In total 4750 valid fixations were analysed. Participants with ID fixated on traffic relevant objects at a rate of 68 percent of the control participants. Furthermore, the males with ID were 9(4.4–18.7) times more likely to fixate on non-traffic relevant objects compared with traffic relevant objects, much higher odds than that of females with ID 1.8(0.4–1.7). Zebra crossings appeared to act as a cue, drawing pedestrians' visual attention to the traffic environment, with both groups more likely to look at traffic relevant objects on/at the zebra crossing (66%: 34%). Future implementation of shared zones needs to be carefully considered in relation to the safety of road users with ID and their capacity to identify and assess salient environmental information.
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| 19. |
- Earl, Robyn, et al.
(författare)
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Visual search strategies of pedestrians with and without visual and cognitive impairments in a shared zone : A proof of concept study
- 2016
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Ingår i: Land use policy. - : Elsevier. - 0264-8377 .- 1873-5754. ; 57, s. 327-334
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Tidskriftsartikel (refereegranskat)abstract
- Shared zones have gained increasing popularity in urban land use and design as a means of incorporating the needs of multiple modes of transport, while at the same time promoting social interaction between users. Interactions within shared zones are based on a set of informal social protocols, communicated via eye contact and social cues. This proof of concept study utilised eye-tracking technology to examine the visual search strategies of individuals, with and without visual and cognitive impairments as they navigated a strategically chosen shared zone. In total 3960 fixations were analysed and the fixations were distributed across the shared zone and a pedestrian crossing. Those with impairments were more likely to fixate on traffic specific areas and objects compared to those without, suggesting that they required more input ascertaining when and where it was safe to perform tasks. However, the duration of fixation was not significantly different for an object whether it was traffic related or not, indicating a global need for increased processing time of the surrounding environment. Shared zones are claimed to increase driver awareness and safety and reduce congestion, but the implications on participation and safety for those with visual and cognitive impairments is yet to be extensively explored.
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| 20. |
- Evans, Kiah L., et al.
(författare)
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The complexity of role balance: Support for the Model of Juggling Occupations
- 2014
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Ingår i: Scandinavian Journal of Occupational Therapy. - : Informa UK Limited. - 1103-8128 .- 1651-2014. ; 21:5, s. 334-347
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Tidskriftsartikel (refereegranskat)abstract
- Objective: This pilot study aimed to establish the appropriateness of the Model of Juggling Occupations in exploring the complex experience of role balance amongst working women with family responsibilities living in Perth, Australia.Methods: In meeting this aim, an evaluation was conducted of a case study design, where data were collected through a questionnaire, time diary, and interview.Results: Overall role balance varied over time and across participants. Positive indicators of role balance occurred frequently in the questionnaires and time diaries, despite the interviews revealing a predominance of negative evaluations of role balance. Between-role balance was achieved through compatible role overlap, buffering, and renewal. An exploration of within-role balance factors demonstrated that occupational participation, values, interests, personal causation, and habits were related to role balance.Conclusions: This pilot study concluded that the Model of Juggling Occupations is an appropriate conceptual framework to explore the complex and dynamic experience of role balance amongst working women with family responsibilities. It was also confirmed that the case study design, including the questionnaire, time diary, and interview methods, is suitable for researching role balance from this perspective.
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