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- 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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| 2. |
- 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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| 3. |
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| 4. |
- 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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| 5. |
- Alkaissi, Aidah, et al.
(författare)
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P6 acupressure increases tolerance to nausogenic motion stimulation in women with high risk for PONV
- 2005
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Ingår i: Canadian Journal of Anesthesia. - 1496-8975. ; 52, s. 703-709
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: In a previous study we noticed that P6 acupressure decreased postoperative nausea and vomiting (PONV) more markedly after discharge. As motion sickness susceptibility is increased by, for example, opioids we hypothesized that P6 acu-pressure decreased PONV by decreasing motion sickness susceptibility. We studied time to nausea by a laboratory motion challenge in a group of volunteers, during P6 and placebo acupressure. Methods: 60 women with high and low susceptibilities for motion sickness participated in a randomized and double-blind study with an active P6 acupressure, placebo acupressure, and a control group (n = 20 in each group). The risk score for PONV was over 50%. The motion challenge was by eccentric rotation in a chair, blindfolded and with chin to chest movements of the head. The challenge was stopped when women reported moderate nausea. Symptoms were recorded. Results: Mean time to moderate nausea was longer in the P6 acu-pressure group compared to the control group. P6 acupressure = 352 (259–445), mean (95% confidence interval) in seconds, control = 151 (121–181) and placebo acupressure = 280 (161–340); (P = 0.006). No difference was found between P6 and placebo acupressure or placebo acupressure and control groups. Previous severity of motion sickness did not influence time to nausea (P = 0.107). The cumulative number of symptoms differed between the three groups (P < 0.05). Fewer symptoms were reported in the P6 acupressure compared to the control group P < 0.009. Overall, P6 acupressure was only marginally more effective than placebo acupressure on the forearms. Conclusion: In females with a history of motion sickness P6 acu-pressure increased tolerance to experimental nauseogenic stimuli, and reduced the total number of symptoms reported.
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| 6. |
- Bergdahl, Björn, et al.
(författare)
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In the Forefront of Development:The New Undergraduate Medical Curriculu
- 2006. - 1
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Ingår i: Celebrating the Past by Expanding the Future: The Faculty of Health Science, Linköping University 1986–2006. - Linköping : Linköping University Electronic Press. - 9185643076 ; , s. 98-102
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 7. |
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| 8. |
- Ericsson, Elisabeth, 1959-, et al.
(författare)
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Long-term improvement of life quality after tonsillotomy in youths
- 2007
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Ingår i: 6th European Congress of Otorhinolaryngology Head and Neck Surgery Wien, Österrike 30 juni-4 juli 2007.
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Konferensbidrag (refereegranskat)abstract
- Objective: This is a one year follow-up to compare the effects of partial tonsil resection using radiofrequency technique (RF), “tonsillotomy” (TT), with total tonsillectomy (TE) (blunt dissection). Obstructive symptoms, tendency for infections and health related quality of life (HRQL) were studied and compared with the HRQL-data from a normal population. Method: The study-group consisted of 76 patients (16-25 years) randomized to TT (n=32) or TE (n=44) with obstructive throat problems with or without recurrent tonsillitis. Short-Form (SF-36) and EuroQul Visual Analogue Scale were used to evaluate HRQL. A questionnaire investigated the degree of obstruction and history of infections. Results: Preoperatively both groups reported significantly lower HRQL in all dimensions of SF-36 compared with the normal population (p<.05- p<.001). After one year, a large improvement (p<.01- p<.001) in both groups in HRQL was found. No differences were found when compared with normal population or between the study-groups. The effect on snoring was the same for both groups and the rate of recurrence of infections was low and not higher in the TT-group. Conclusion: Preoperative obstructive problems, in combination with recurrent tonsillitis have a negative impact on HRQL. Both TT and TE-groups demonstrate large improvements on HRQL, infections and obstructive problems one year after surgery, indicating that both surgical methods are equally effective. With its reduced post-operative complications, less pain, shorter recovery time, and cost reduction, tonsillotomy with the radiofrequency technique ought to be considered as the method of choice.
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| 9. |
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| 10. |
- Ericsson, Elisabeth, 1959-, et al.
(författare)
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Long-Term Improvement of Quality of Life as a Result of Tonsillotomy (With Radiofrequency Technique) and Tonsillectomy in Youths
- 2007
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Ingår i: The Laryngoscope. - 0023-852X .- 1531-4995. ; 117:7, s. 1272-1279
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Tidskriftsartikel (refereegranskat)abstract
- Objective: This is a 1 year follow-up to compare the effects of partial tonsil resection using the radiofrequency technique (RF) tonsillotomy (TT) with total tonsillectomy (TE) (blunt dissection). Obstructive symptoms, tendency for infections, and health-related quality of life (HRQL) were studied and compared with the HRQL data from a normal population.Method: The study group consisted of 74 patients (16-25 yr old) randomized to TT (n = 31) or TE (n = 43) with obstructive throat problems with or without recurrent tonsillitis. The Short Form 36 (SF-36) and EuroQul Visual Analogue Scale were used to evaluate HRQL. A questionnaire investigated the degree of obstruction and history of infections.Results: Preoperatively, both groups reported significantly lower HRQL in all dimensions of the SF-36 compared with the normal population (P < .05-P < .001). After 1 year, a large improvement (P < .01-P < .001) in both groups in HRQL was found. No differences were found when these groups were compared with the normal population or between the study groups. The effect on snoring was the same for both groups, and the rate of recurrence of infections was low and not any higher in the TT group.Conclusion: Preoperative obstructive problems in combination with recurrent tonsillitis have a negative impact on HRQL. Both the TT and TE groups demonstrated large improvements on HRQL, infections, and obstructive problems 1 year after surgery, indicating that the surgical methods are equally effective. With its reduced postoperative complications, less pain, shorter recovery time, and cost reduction, TT with RF should be considered the method of choice.
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