Sports experts' unique perception of time duration based on the processing principle of an integrated model of timing.
ABSTRACT: Background:Duration perception is an essential part of our cognitive and behavioral system, helping us interact with the outside world. An integrated model of timing, which states that the perceived duration of a given stimulus is based on the efficiency of information extraction, was recently set forth to improve current understanding of the representation and judgment of time. However, the prediction from this model that more efficient information extraction results in longer perceived duration has not been tested. Thus, the aim of this study is to investigate whether sports experts, as a group of individuals with information extraction superiority in situations relevant to their sport skill, have longer duration perceptions when they view expertise-related stimuli compared with others with no expertise/experience. Methods:For this study, 81 subjects were recruited based on a prior power analysis. The sports experts group had 27 athletes with years of professional training in diving; a wrestler group and a nonathlete group, with each of these groups having 27 subjects, were used as controls. All participants completed a classic duration reproduction task for subsecond and suprasecond durations with both the diving images and general images involved. Results:The divers reproduced longer durations for diving stimuli compared with general stimuli under both subsecond and suprasecond time ranges, while the other samples showed the opposite pattern. Furthermore, the years of training in diving were positively correlated with the magnitude of the prolonged reproduction duration when divers viewed diving stimuli. Moreover, the diver group showed a more precise duration perception in subsecond time range for general stimuli compared with the wrestlers and nonathletes. Conclusion:The results suggest that sports experts perceive longer duration when viewing expertise-related stimuli compared with others with no expertise/experience.
Project description:Sports experts represent a population of people who have acquired expertise in sports training and competition. Recently, the number of studies on sports experts has increased; however, neuroanatomical changes following extensive training are not fully understood. In this study, we used cortical thickness measurement to investigate the brain anatomical characteristics of professional divers with extensive training experience. A comparison of the brain anatomical characteristics of the non-athlete group with those of the athlete group revealed three regions with significantly increased cortical thickness in the athlete group. These regions included the left superior temporal sulcus, the right orbitofrontal cortex and the right parahippocampal gyrus. Moreover, a significant positive correlation between the mean cortical thickness of the right parahippocampal gyrus and the training experience was detected, which might indicate the effect of extensive training on diving players' brain structure.
Project description:The ability of subjects to identify and reproduce brief temporal intervals is influenced by many factors whether they be stimulus-based, task-based or subject-based. The current study examines the role individual differences play in subsecond and suprasecond timing judgments, using the schizoptypy personality scale as a test-case approach for quantifying a broad range of individual differences. In two experiments, 129 (Experiment 1) and 141 (Experiment 2) subjects completed the O-LIFE personality questionnaire prior to performing a modified temporal-bisection task. In the bisection task, subjects responded to two identical instantiations of a luminance grating presented in a 4deg window, 4deg above fixation for 1.5 s (Experiment 1) or 3 s (Experiment 2). Subjects initiated presentation with a button-press, and released the button when they considered the stimulus to be half-way through (750/1500 ms). Subjects were then asked to indicate their 'most accurate estimate' of the two intervals. In this way we measure both performance on the task (a first-order measure) and the subjects' knowledge of their performance (a second-order measure). In Experiment 1 the effect of grating-drift and feedback on performance was also examined. Experiment 2 focused on the static/no-feedback condition. For the group data, Experiment 1 showed a significant effect of presentation order in the baseline condition (no feedback), which disappeared when feedback was provided. Moving the stimulus had no effect on perceived duration. Experiment 2 showed no effect of stimulus presentation order. This elimination of the subsecond order-effect was at the expense of accuracy, as the mid-point of the suprasecond interval was generally underestimated. Response precision increased as a proportion of total duration, reducing the variance below that predicted by Weber's law. This result is consistent with a breakdown of the scalar properties of time perception in the early suprasecond range. All subjects showed good insight into their own performance, though that insight did not necessarily correlate with the veridical bisection point. In terms of personality, we found evidence of significant differences in performance along the Unusual Experiences subscale, of most theoretical interest here, in the subsecond condition only. There was also significant correlation with Impulsive Nonconformity and Cognitive Disorganisation in the sub- and suprasecond conditions, respectively. Overall, these data support a partial dissociation of timing mechanisms at very short and slightly longer intervals. Further, these results suggest that perception is not the only critical mitigator of confidence in temporal experience, since individuals can effectively compensate for differences in perception at the level of metacognition in early suprasecond time. Though there are individual differences in performance, these are perhaps less than expected from previous reports and indicate an effective timing mechanism dealing with brief durations independent of the influence of significant personality trait differences.
Project description:Pre-performance routines (PPRs) are essential motor skills prior to a competition for athletes. But we believe that a specific kind of sport has its own PPRs. Using a qualitative research design, this study conducted in-depth interviews with 14 elite Chinese athletes in competitive diving and their coaches as well as observed and analyzed the behaviors of 13 athletes during diving competitions. The results showed that the divers' PPRs were constituted of four components (psychological skills, pace setting, mastering competition progress, and behavioral strategies), which could be divided into 20 core categories, with the entire diving process divided into three sections and ten stages, including 13 subcategories in off-platform, 12 subcategories in on-platform and the diving stage. Thus, patterns in the PPRs for divers were established and a clear and comprehensive picture of the diving process, as well as the psychological characteristics and behavioral patterns of athletes during the process, were obtained. The findings entail implications for developing PPRs for diving athletes and future studies on PPRs in other competitive diving and other sports.
Project description:Citizen Science (CS) strengthens the relationship between society and science through education and engagement, with win-win benefits. Marine Citizen Science (MCS) is increasingly popular, thanks to society's growing interest in marine environments and marine issues. Scuba diving significantly increases the potential of MCS, thanks to the skills and behavioural properties of people who participate in the sport. To be able to exploit this potential, however, MCS needs to face challenges related to CS, to scuba diving activities and to the broader scuba diving industry. In particular, engagement and recruitment of potential volunteers, as well as retention of active participants, represent key milestones. In order to reach these milestones, information is required on current participation levels of scuba divers in MCS, as well as the motivations behind participation, and the opinions held by potential participants in MCS. This study explored different case studies and methods of data collection to provide an overview of actual and potential participation in MCS by the scuba diving community. The results show that scuba divers, whether active or potential marine citizen scientists, are well disposed towards MCS. Some barriers, however, prevent the full participation of scuba divers as marine citizen scientists. Certain barriers extend beyond the control of both divers and MCS projects, while others, such as limited access to MCS projects and poor feedback after participation, can and should be addressed. The recommendations of this research provide strategic direction to MCS, so that the broad scuba diving community can be successfully integrated into MCS. These recommendations acknowledge the important role played by stakeholders in the scuba diving industry, as well as professional intermediaries and hired experts.
Project description:Scuba diving experience-which can include accumulated diving experience and familiarity with a diving location-is an important descriptor of diver specialisation and behaviour. Formulating and applying generalisations on scuba diving experience and its effects could assist the management of diving destinations around the world. This requires research that tests whether the influences of scuba diving experience are consistent across divers' segments at different locations. The study assessed and compared the influence of scuba diving experience at two study areas in Italy and Mozambique. Scuba divers (N = 499) participated in a survey of diver segmentation, experience, and perceptions. The influence of diving experience on perceptions was determined using canonical correspondence analysis (CCA). Experienced divers provided positive self-assessments, were less satisfied with dive sites' health and management, and viewed the impacts of scuba diving activities less critically than novice divers. Scuba diving experience exerted similar influences on divers, regardless of the study area. However, remarkable differences also emerged between the study areas. Therefore, the use of generalisations on scuba diving experience remains a delicate issue. Recommendations were formulated for the management of experienced scuba diving markets and for the use of generalisations on diving experience to manage diving destinations.
Project description:There is evidence that timing processes in the suprasecond scale are modulated by attentional mechanisms; in addition, some studies have shown that attentional mechanisms also affect timing in the subsecond scale. Our aim was to study eye movements and pupil diameter during a temporal bisection task in the subsecond range. Subjects were trained to discriminate anchor intervals of 200 or 800 msec, and were then confronted with intermediate durations. Eye movements revealed that subjects used different cognitive strategies during the bisection timing task. When the stimulus to be timed appeared randomly at a central or 4 peripheral positions on a screen, some subjects choose to maintain their gaze toward the central area while other followed the peripheral placement of the stimulus; some others subjects used both strategies. The time of subjective equality did not differ between subjects who employed different attentional mechanisms. However, differences emerged in the timing variance and attentional indexes (time taken to initial fixation, latency to respond, pupil dilatation and duration and number of fixations to stimulus areas). Timing in the subsecond range seems invariant despite the use of different attentional strategies. Future research should determine whether the selection of attentional mechanisms is related to particular timing tasks or instructions or whether it represents idiosyncratic cognitive "styles".
Project description:Semi-aquatic mammals have secondarily returned to the aquatic environment, although they spend a major part of their life operating in air. Moving both on land, as well as in, and under water is challenging because such species are considered to be imperfectly adapted to both environments. We deployed accelerometers combined with a depth sensor to study the diving behavior of 12 free-living Eurasian beavers <i>Castor fiber</i> in southeast Norway between 2009 and 2011 to examine the extent to which beavers conformed with mass-dependent dive capacities, expecting them to be poorer than wholly aquatic species. Dives were generally shallow (<1 m) and of short duration (<30 s), suggesting that the majority of dives were aerobic. Dive parameters such as maximum diving depth, dive duration, and bottom phase duration were related to the effort during different dive phases and the maximum depth reached. During the descent, mean vectorial dynamic body acceleration (VeDBA-a proxy for movement power) was highest near the surface, probably due to increased upthrust linked to fur- and lung-associated air. Inconsistently though, mean VeDBA underwater was highest during the ascent when this air would be expected to help drive the animals back to the surface. Higher movement costs during ascents may arise from transporting materials up, the air bubbling out of the fur, and/or the animals' exhaling during the bottom phase of the dive. In a manner similar to other homeotherms, beavers extended both dive and bottom phase durations with diving depth. Deeper dives tended to have a longer bottom phase, although its duration was shortened with increased VeDBA during the bottom phase. Water temperature did not affect diving behavior. Overall, the beavers' dive profile (depth, duration) was similar to other semi-aquatic freshwater divers. However, beavers dived for only 2.8% of their active time, presumably because they do not rely on diving for food acquisition.
Project description:Breath-hold divers (BHD) experience repeated bouts of severe hypoxia and hypercapnia with large increases in blood pressure. However, the impact of long-term breath-hold diving on cerebrovascular control remains poorly understood. The ability of cerebral blood vessels to respond rapidly to changes in blood pressure represents the property of dynamic autoregulation. The current investigation tested the hypothesis that breath-hold diving impairs dynamic autoregulation to a transient hypotensive stimulus. Seventeen BHD (3 women, 11?±?9 yr of diving) and 15 healthy controls (2 women) completed two or three repeated sit-to-stand trials during spontaneous breathing and poikilocapnic conditions. Heart rate (HR), finger arterial blood pressure (BP), and cerebral blood flow velocity (BFV) from the right middle cerebral artery were measured continuously with three-lead electrocardiography, finger photoplethysmography, and transcranial Doppler ultrasonography, respectively. End-tidal carbon dioxide partial pressure was measured with a gas analyzer. Offline, an index of cerebrovascular resistance (CVRi) was calculated as the quotient of mean BP and BFV. The rate of the drop in CVRi relative to the change in BP provided the rate of regulation [RoR; (?CVRi/?T)/?BP]. The BHD demonstrated slower RoR than controls (P ? 0.001, d?=?1.4). Underlying the reduced RoR in BHD was a longer time to reach nadir CVRi compared with controls (P = 0.004, d?=?1.1). In concert with the longer CVRi response, the time to reach peak BFV following standing was longer in BHD than controls (P = 0.01, d?=?0.9). The data suggest impaired dynamic autoregulatory mechanisms to hypotension in BHD. NEW & NOTEWORTHY Impairments in dynamic cerebral autoregulation to hypotension are associated with breath-hold diving. Although weakened autoregulation was observed acutely in this group during apneic stress, we are the first to report on chronic adaptations in cerebral autoregulation. Impaired vasomotor responses underlie the reduced rate of regulation, wherein breath-hold divers demonstrate a prolonged dilatory response to transient hypotension. The slower cerebral vasodilation produces a longer perturbation in cerebral blood flow velocity, increasing the risk of cerebral ischemia.
Project description:<b>Introduction:</b> When divers are compressed to water depths deeper than 150 meter sea water (msw), symptoms of high-pressure neurological syndrome (HPNS) might appear due to rapid increase in pressure on the central nervous system during compression. The aim of this study was to first operate a new computerized tool, designed to monitor divers' wellbeing and cognitive function, and to record the results. The second aim was to evaluate the feasibility and validity of the Physiopad software and HPNS questionnaires as a new tool for monitoring divers wellbeing in an operational setting, including sensible visualization and presentation of results. <b>Methods:</b> The Physiopad was operated onboard Deep Arctic (TechnipFMC Diving Support Vessel). The diving work was performed between 180 and 207 msw. The data from 46 divers were collected from the HPNS questionnaires, Hand dynamometry test, Critical Flicker Fusion Frequency test (CFFF), Adaptive Visual Analog Scale (AVAS), Simple Math Process (MathProc test), Perceptual Vigilance Task (PVT), and Time Estimation Task (time-wall). <b>Result:</b> Diver's subjective evaluation revealed different symptoms, possibly also HPNS related, which lasted from 1 to 5 days in storage, with the common duration being 1 day. The results from Physiopad battery testing showed no signs of significant neurological alteration. <b>Conclusion:</b> The present study showed that there was no association between subjective measurements of HPNS and neuropsychometric test results. We also confirmed the feasibility of using the computerized test battery to monitor saturation divers at work. The HPNS battery and Physiopad software could be an important tool for monitoring diver's health in the future. This tool was not used during the Bahr Essalam project to operationally evaluate any HPNS effect on divers as data analysis was performed post-project.
Project description:Foraging theory predicts that breath-hold divers adjust the time spent foraging at depth relative to the energetic cost of swimming, which varies with buoyancy (body density). However, the buoyancy of diving animals varies as a function of their body condition, and the effects of these changes on swimming costs and foraging behaviour have been poorly examined. A novel animal-borne accelerometer was developed that recorded the number of flipper strokes, which allowed us to monitor the number of strokes per metre swam (hereafter, referred to as strokes-per-metre) by female northern elephant seals over their months-long, oceanic foraging migrations. As negatively buoyant seals increased their fat stores and buoyancy, the strokes-per-metre increased slightly in the buoyancy-aided direction (descending), but decreased significantly in the buoyancy-hindered direction (ascending), with associated changes in swim speed and gliding duration. Overall, the round-trip strokes-per-metre decreased and reached a minimum value when seals achieved neutral buoyancy. Consistent with foraging theory, seals stayed longer at foraging depths when their round-trip strokes-per-metre was less. Therefore, neutrally buoyant divers gained an energetic advantage via reduced swimming costs, which resulted in an increase in time spent foraging at depth, suggesting a foraging benefit of being fat.