The Mechanism In The Effect Of Conceptual Knowledge On Action Processing In Table Tennis Players

The experience gained from long-term sport training makes athletes better than novices and non-athletes in action processing within their domain of expertise.Many studies based on the forward model and mirror neuron theory propose that this expert advantage is mainly due to the ability of athletes to quickly extract the opponent’s kinematic information based on stored perceptual movement experience,and to efficiently process the movement by motion simulation.These research and the forward model mostly refer to the more concrete level of action processing,such as the trajectory and the velocity profile of the action.However,the more abstract level of understanding such as the goal and the intention of the action is ignored.Based on the two-pathway model and ‘action semantics’,the current study aimed to explore the mechanism on the effect of conceptual experience on action processing in table tennis players,by comparing table tennis players with different levels of experience and non-athletes.In the first experiment,we manipulated the congruence between body kinematics and the subsequent ball trajectory in videos of an expert performing table tennis serves and compared the N400 amplitudes elicited by expert athletes,novices and non-athletes.In the second and third experiments,experts and non-athletes completed a dual-task and they were required to memorize different kinds of stimuli in the process of action anticipation on the ball trajectory,including hand verbs,leg verbs,spatial location and no stimuli.The performance of action anticipation and the N400 amplitude were recorded and analyzed.Finally,the fourth and fifth experiments used magnetic resonance imaging to observe the changes of brain function and structure in semantic network of experts.The results showed that:(1)In the first experiment,the N400-like amplitudes were larger in incongruent condition than congruent condition for both experts and novices,but not for controls.The significant correlation between response accuracy and N400-like effect was only found in the expert group.(2)In the second experiment,the performance decreased by hand-verb interference compared to spatial interference only in experts.(3)In the third experiment,the N400-like effect was higher in hand-verb interference condition than leg-verb in experts,while there were no significant differences between interference conditions in controls.(4)In the fourth experiment,the activations were higher in experts than controls in sensorimotor system(right precentral gyrus and postcentral gyrus)and semantic system(the posterior inferior parietal lobe(angular gyrus),middle temporal gyrus,and ventromedial prefrontal cortex).(5)In the fifth experiment,experts exhibited greater fractional anisotropy(FA)in sections of the left/right corticospinal tract,left/rightinferior fronto-occipital fasciculus,left inferior longitudinal fasciculus and right superior longitudinal fasciculus,compared to controls.We concluded that:(1)Conceptual knowledge can improve action processing in table tennis athletes.(2)The expert athletes rely more on conceptual knowledge than novices.(3)Semantic regions are also involved in action processing except for sensorimotor system.(4)The long-term sport training improves the integrity of the white matter that assists in efficient communication between gray matter regions in both sensorimotor and semantic systems,which may be another potential neural mechanism of expert advantages.