RESUMO
Although vision is the dominating sensory system in sports, many situations require multisensory integration. Faster processing of auditory information in the brain may facilitate time-critical abilities such as reaction speed however previous research was limited by generic auditory and visual stimuli that did not consider audio-visual characteristics in ecologically valid environments. This study investigated the reaction speed in response to sport-specific monosensory (visual and auditory) and multisensory (audio-visual) stimulation. Neurophysiological analyses identified the neural processes contributing to differences in reaction speed. Nineteen elite badminton players participated in this study. In a first recording phase, the sound profile and shuttle speed of smash and drop strokes were identified on a badminton court using high-speed video cameras and binaural recordings. The speed and sound characteristics were transferred into auditory and visual stimuli and presented in a lab-based experiment, where participants reacted in response to sport-specific monosensory or multisensory stimulation. Auditory signal presentation was delayed by 26 ms to account for realistic audio-visual signal interaction on the court. N1 and N2 event-related potentials as indicators of auditory and visual information perception/processing, respectively were identified using a 64-channel EEG. Despite the 26 ms delay, auditory reactions were significantly faster than visual reactions (236.6 ms vs. 287.7 ms, p < 0.001) but still slower when compared to multisensory stimulation (224.4 ms, p = 0.002). Across conditions response times to smashes were faster when compared to drops (233.2 ms, 265.9 ms, p < 0.001). Faster reactions were paralleled by a lower latency and higher amplitude of the auditory N1 and visual N2 potentials. The results emphasize the potential of auditory information to accelerate the reaction time in sport-specific multisensory situations. This highlights auditory processes as a promising target for training interventions in racquet sports.
RESUMO
PURPOSE: Stroboscopic training is suggested to improve visuomotor abilities in sports. However, previous research has primarily focused on untrained participants and only considered behavioral data. Because visuomotor performance is substantially determined by neural visual processes, this study aimed to examine the effects of stroboscopic training on visuomotor performance and neural visual function of athletes. METHODS: A total of 10 German top-level badminton players (intervention: n = 5 and control: n = 5) participated in this study. Over a 4-week training period, athletes performed badminton-specific visuomotor tasks either wearing shutter glasses (intervention) or under normal visual conditions (control). Prior to and after the training period, behavioral smash-defense tests and neurophysiologic investigations of the N2 motion onset visual evoked potential were used to identify modulations in the athletes' visuomotor performance and visual perception speed, respectively. RESULTS: Badminton training improved visuomotor performance in both groups; however, stroboscopic training resulted in superior posttraining performance compared with normal visual conditions (P = .007). Training-induced modulations in N2 latency did not reach significance, although a strong relationship was observed between changes in N2 latency and changes in visuomotor performance (r = -.55), indicating that higher performance gains following training were associated with a stronger reduction in N2 latency. CONCLUSIONS: The results indicate that stroboscopic training may be more effective than conventional visuomotor training for improving visuomotor abilities even in athletes performing at high skill levels. Furthermore, visuomotor performance gains could potentially be mediated by neural adaptations in the visual motion system. These findings should be confirmed for athletes from different disciplines.