A Study On Visual Search Strategies, Prediction Ability And Their Neuromechanism Of Various Role In Women Volleyball Players

One of the characteristics of expertise in many reactive skills is the ability to makeuse of advance visual information to anticipate behavioral events so as to adapt to theopponent’s movement patterns. The defense in volleyball is a typical reactive skill.Decision making strategies of visual search and advance anticipation plays a key rolein volleyball game. Some studies showed that experts’ superior performance wasrelated to specific roles. Whether the experience of roles influence informationprocessing arose great interest.Guided by deliberate practice theory and using the realistic games videos asmaterials, the present study systematically discussed the neuromechanism ofvolleyball players of various roles when blocking anti-front and defense back.The result of(the) study shows:(1) While predicting and judging the direction ofattacking, visual search speed of libero’s group is quickly with low frequency ofvisual search, lower accuracy, short latency of P1, P2wave and low amplitude ofwave in the occipital zone, parietal zone and central zone. Visual search speed ofco-spiker’s group was quickly with high frequency of visual search, high accuracy topredict. The latency of P1is short and the amplitude is large.(2) While predicting andjudging the direction of attacking, the latency of P2of libero’s group is short and theamplitude is low; while the latency of P2was short and the amplitude was low inspiker and assistant setter’ group.(3) While predicting and judging the direction ofattacking, the latency of P3of spiker’s group under2bits conditions of storming issignificantly shorter than that of co-spiker’s group. Under4bits conditions ofstorming, the latency of P3of assistant setter’ group is shorter than that of co-spiker’sgroup significantly. The P3wave amplitude of groups of assistant setter, spikers andco-spikers is bigger than that of setter and libero’s group.(4) While predicting andjudging the passing directions of the setter, there was no remarkable differencebetween different role’s athletes’ reaction speeds and rate of accuracy. The latency ofP1, N1, P2, P3of setters’ and liberos’ groups was short, with small amplitude andlow frequency to search but it was reverse in co-attacking and reinforcing group. Thefixation rate of those who watch in the front was higher than that who pass backly butthe rate of correct response was low.(5) While predicting the tactics type of setters,the speed and rate of accuracy drop significantly but the difference among the roleswas notsignificant. The fixation rate on setters, ball, co-spiker area and setter’s trunk,hand-ball, arm area was relatively high. The P1latency of spikers, co-spikers wasremarkably longer, and the amplitude was relatively small; The intensity of activationin the occipital zone of cerebral cortex of spiker group was remarkable high while itwas contrary to the liberos. P3amplitude of passing quickly attack was greater thanthat of storming attack.The conclusions were as follows.(1) Different roles in volleyball game useddifferent strategy of visual search. Mean duration time of spikers and co-spikers wasmuch shorter and the correct rate of reaction was high, indicating that this was a kindof effective search strategy.(2) The high frequency of visual search, high intensity ofactivation in cerebral cortex and more psychological resource to take up resulted inhigh rate of correct prediction. Higher speed of search was followed by higheractivation of nerve.(3) The characteristics of visual search was related to roles. They pay close attention to the information that correlates with role’s task and used morepsychological resources. The fixation rate of co-spikers on front quick ball was higherthan that of the spiker group; The fixation rate of spikers and co-spikers on legs washigher than liberos.(4) When predicting the direction of spike, the expectancy ofrole’s task influenced the proneness of perceptual motor reaction. The time ofactivation in cerebral cortex of setters and liberos was long with relatively lowerintensity and it was contrary to that of spikers and co-spikers with better performanceof prediction; The time of activation in cerebral cortex of the assistant setters, spikersplayers was short when activating, activate the intensity largly, notice thatconcentration degree was high, put psychological resources to use more, hasimproved the performance judged of predicting. The assistant setters，the spikers, theco-spikers remarkable and relatively large in amplitude evoked P1, P2, P3from theoccipital zone, parietal zone, central zone, parieta occipital zone and central parietalzone, indicating that good prediction performance might related to these indexes.(5)At predicting directioning of spiking, spike player, area of ball and spike player trunkand arm position were main information sources.(6) When Predicting the direction ofsetters’ passing, it is the setters, co-spikers, ball and passer, the ball-hand area, thetrunk that were the main information area, and hand-ball, the trunk area of the setterdiscern in the main information area to identify setters fixation rate on arms of settersgroup and co-spikers group who had meticulous vision process of setters’ movementpatterns.(7) The degree of difficulty of movements influenced the fixation rate. Frontpassing was more difficult to discern the pattern than back passing. The accuracy ofpredicting and judging direction of spike in intermediate zone of the net was higherthan both sides of the net. The prediction of the scene attacked fast took up morepsychological resources.The main theory of this research has such contribution as follows. Firstly, throughtwo kinds of prediction in volleyball defending conditions, characteristics of visualsearch and prediction of different roles were discussed in order to offer theory supportfor training in the special location. Secondly, adopt the match video record andproduce live and combine the eye movement and ERP technology explored the visualsearch and anticipation in volleyball which improved ecology result but offer thepossible training mode for perceptual motor skill training. Thirdly, using thetechnology of eye movement and ERP to probe into speciality advantage andmechanism of vision searches and the cranial nerve activity expanded the version ofthe study of perceptual motor skill.