Biomedical subjects

John F Golding

Publications and source records attributed to John F Golding.

8 recordsLinked to original sources

PubMed2006

Motion sickness susceptibility.

Motion sickness can be caused by a variety of motion environments (e.g., cars, boats, planes, tilting trains, funfair rides, space, virtual reality) and given a sufficiently provocative motion stimulus almost anyone with a functioning vestibular system can be made motion sick. Current hypotheses of the 'Why?' of motion sickness are still under investigation, the two most important being 'toxin detector' and the 'vestibular-cardiovascular reflex'. By contrast, the 'How?' of motion sickness is better understood in terms of mechanisms (e.g., 'sensory conflict' or similar) and stimulus properties (e.g., acceleration, frequency, duration, visual-vestibular time-lag). Factors governing motion sickness susceptibility may be divided broadly into two groups: (i) those related to the stimulus (motion type and provocative property of stimulus); and (ii) those related to the individual person (habituation or sensitisation, individual differences, protective behaviours, administration of anti-motion sickness drugs). The aim of this paper is to review some of the more important factors governing motion sickness susceptibility, with an emphasis on the personal rather than physical stimulus factors.

Animals↗

PubMed2006

Increasing cognitive load with increasing balance challenge: recipe for catastrophe.

The variety of sometimes contradictory results of studies of the impact of secondary cognitive tasks on postural balance may be attributed to the heterogeneity of balance challenges and tasks deployed and frequent lack of quantitative comparability of tasks. We deployed a wide range of quantitatively graded difficulties of both balance challenge and cognitive tasking to obtain an overview of the spectrum of their interactions in a multi-tasking situation. A differential comparison of the effects of verbally versus spatially loaded tasks, balanced for difficulty, was made and unlike any other study, we contrived to incorporate falls as an experimental variable. In the first study subjects stood in tandem on beams of either 2, 3 and 6 cm or 3, 6 and 8 cm width (according to 'best performance' ability) while performing mental verbal or spatial 'Stroop' tasks. The design was a between groups (sixteen subjects each) comparison (to reduce learning effect) of sway, fall rate and task error, balanced for order. Measurements were taken of centre of pressure, sway velocity at the hip and head displacement. For any beam width there were no within-subject correlations between sway magnitudes and frequency of falls. Spatial task errors increased with balance challenge (hence with magnitude of sway) but verbal performance was maintained independently of balance challenge. The results of the first study provided statistical power estimates for the design of the second focussed experiment which made a within group (twenty four subjects) comparison of the impact of spatial versus verbal tasks on balancing on the hardest beam. The spatial task significantly elevated the incidence of falls whereas the verbal task had no effect on fall rate. The spatial task raised the incidence of falling by 50% (P = 0.0008) in comparison with 'no task'. The verbal task had no effect (P = 0.07). We conclude that sway magnitude is a poor index of multi-task load. Multi-tasking can increase the chance of falling and spatial processing may have a specific impact on balance. The significant elevation of fall frequency during cognitive tasking shows that the 'posture first' principal can be transgressed although the necessary condition for transgression may be that the subject is willing to take risks believing that he can arrest any fall.

Accidental Falls↗

PubMed2005

Motion sickness.

PURPOSE OF REVIEW: The public's longstanding resigned tolerance to motion sickness threatens to change, due to the widespread introduction of nauseogenic tilting trains and the increasing use of virtual reality immersion. RECENT FINDINGS: Scientific effort over the last 5 years has focused on precise evaluation of the stimuli that provoke sickness and on the development of behavioural and new pharmacological interventions to suppress sickness. SUMMARY: The precise mechanical ride characteristics of vehicles that provoke sickness have been identified and this will lead to guidelines for future engineering design, especially for suspension systems that compensate for inertial tilt, and recommendations for passengers at risk. The frequency characteristics of motion provoking sickness have been defined with greater precision and identified with shifts in perception of motion versus orientation, and changes in the quality of reflex eye movements. Ability to modify readily the time constant of vestibular 'velocity store' has emerged as a potential candidate marker of successful motion sickness habituation. Behavioural 'autogenic' countermeasures to the development of sickness, such as controlled breathing, which can be implemented readily, are shown to have significant ameliorating effects on nausea and are of value for short term moderate exposures. New classes of pharmacological agents such as N-methyl-D-aspartate antagonists and 5HT1a receptor agonists show promise in animals but await trials in humans.

Antiemetics↗

PubMed2005

Effect of a novel motion desensitization training regime and controlled breathing on habituation to motion sickness.

To study whether controlled breathing, known to ameliorate motion sickness, speeds habituation to nauseogenic motion when used in a novel accelerated training regime, 30 participants (13 men, 17 women, ages 18-51 years) were randomized to either a Breathing group or a Control group. Randomization was balanced for rotation tolerance measured during a first exposure to off-vertical axis rotation (OVAR 72 degrees sec.(-1)). Participants subsequently received four exposures to OVAR in 1-hr. (accelerated training). The Breathing group followed taped instructions to control their breathing during training and when retested the next day. There was overall habituation with stimulus repetition, shown by an increase in tolerance for motion, a reduction in symptoms, and speeded recovery times on retesting. There was a tendency for greater habituation with controlled breathing.

Adolescent↗

PubMed2005

Motion sickness susceptibility fluctuates through the menstrual cycle.

INTRODUCTION: Surveys of transportation by sea, land, and air indicate that women are more susceptible to motion sickness than men, showing higher incidences of vomiting and reporting more symptoms such as nausea. The cause of this greater motion sickness susceptibility in women is unknown. One suggestion is that it is due to the functioning of the female endocrine system, but there are contradictions between existing studies. HYPOTHESIS: Motion sickness in women varies across the menstrual cycle. METHODS: There were 12 healthy women, age 24.4 +/- 6.6 yr (mean +/- SD), not using contraceptive medication, who were exposed to a provocative cross-coupled (Coriolis) motion continued to the point of moderate nausea. The motion stimulus was whole body rotation on a turntable, during which subjects executed head tilts of approximately 45 degrees in batches of eight spaced at 30-s intervals during a staircase profile of rotational velocity which commenced from stationary and incremented in steps of 3 degrees x s(-1) every 30 s. Subjects were tested on: A.) day 5 'menstruation'; B.) day 12 'ovulatory'; C.) day 19 'mid-luteal'; and D.) day 26 'pre-menstrual,' according to a design counter-balanced for order. RESULTS: Mean +/- SD sequences of head movements required to achieve moderate nausea were: A.) 13.7 +/- 2.8; B.) 14.3 +/- 4.5; C.) 15.4 +/- 6.6; and D.) 16.9 +/- 6.1. The difference between A and D was significant (p < 0.05, 2-tailed). CONCLUSIONS: There was a trend indicating that motion sickness susceptibility was maximal at day 5 'menstruation', decreasing through days 12 and 19 to a minimum at day 26 'pre-menstrual', to a small but significant extent. However, it is unlikely that this can fully account for the greater susceptibility in women since the magnitude of fluctuation in susceptibility across the cycle is only around one-third of the overall difference between male and female susceptibility.

Adolescent↗

PubMed2003

Effect of breathing supplemental oxygen on motion sickness in healthy adults.

OBJECTIVE: To compare the effects of breathing supplemental oxygen vs air on alleviating motion sickness in healthy adults. SUBJECTS AND METHODS: Between April and July 2002, 20 healthy subjects were exposed to a provocative motion on 2 occasions (1-week interval) according to a randomized, counterbalanced, crossover design. During motion, subjects rated their nausea (1, no symptoms, to 4, moderate nausea) every 30 seconds. Once mild nausea occurred, subjects began breathing supplemental oxygen or air through a face mask. Motion ceased when moderate nausea occurred, but subjects continued breathing study gases for 5 minutes while recovering. Recovery was assessed for 20 minutes after motion. RESULTS: There were no significant differences in the rate of increase in symptom severity or the rate of recovery between the 2 conditions. CONCLUSION: Breathing supplemental oxygen had no advantage over breathing air in reducing motion sickness in healthy adults.

Adult↗

PubMed2003

Suppression of sickness by controlled breathing during mildly nauseogenic motion.

INTRODUCTION: Anecdotal reports from aviators indicate that controlled breathing is used as a countermeasure for motion sickness. We report a trial on the effectiveness of focused, regular breathing on motion sickness. METHODS: Experiment 1 compared the effects of controlled breathing vs. a counting task on subjective ratings of motion sickness and associated symptoms (n = 12). Experiment 2 investigated the effects of attention (n = 12) on these measures by comparing the counting task with no task. Motion sickness was induced by whole body pitch oscillations (0.2 Hz, +/- 20 degrees peak amplitude) while subjects viewed a video image of the environment oscillating in 180 degrees counter phase. Subjects performed controlled breathing, counting, or no task from the onset of mild nausea to an endpoint of moderate nausea or 30 min motion exposure, whichever came first. RESULTS: Experiment 1: The mean time to reach motion endpoint was significantly longer (p = 0.01) for controlled breathing (21.3 min) than for counting (15.1 min). Controlled breathing also prolonged the time tolerated with nausea and reduced the recovery time after motion cessation. Experiment 2: The counting task had no effect on baseline motion sickness susceptibility. CONCLUSION: Controlled breathing may be effective for controlling nausea.

Adult↗

PubMedDate not supplied

Behavioral methods of alleviating motion sickness: effectiveness of controlled breathing and a music audiotape.

BACKGROUND: Behavioral countermeasures for motion sickness would be advantageous because of the side effects of antiemetic drugs, but few alternative treatments are available. The objective of this study was to compare the effectiveness of controlling breathing and listening to a music audiotape designed to reduce motion sickness symptoms, on increasing tolerance to motion-induced nausea. METHOD: Twenty-four healthy subjects were exposed to nauseogenic Coriolis stimulation on a rotating turntable under three conditions: whilst focusing on controlling breathing; listening to a music audiotape; or without intervention (control). The three conditions were performed by each subject according to a replicated factorial design at 1-week intervals at the same time of day. Ratings of motion sickness were obtained every 30 seconds. Once a level of mild nausea was reached subjects commenced controlling breathing or listened to the music audiotape. Motion was stopped after the onset of moderate nausea. RESULTS: Mean (+/- SD) motion exposure time in minutes tolerated before the onset of moderate nausea was significantly longer (p <.01) for controlling breathing (10.7 +/- 5.6 min) and longer (p <.01) for music (10.4 +/- 5.6 min) compared with control (9.2 +/- 5.9 min). CONCLUSIONS: Both controlling breathing and the music audiotape provided significant protection against motion sickness and with similar effectiveness. These nonpharmacologic countermeasures are only half as effective as standard doses of anti-motion sickness drugs, such as oral scopolamine; however, they are easy to implement and free of side effects.

Adult↗