Mechanisms of Action Anticipation in Table Tennis Players: A Multivoxel Pattern Analysis Study.

An exceptional ability to accurately anticipate an opponent's action is paramount for competitive athletes and highlights their experiential mastery. Despite conventional associations of action observation with specific brain regions, neuroimaging discrepancies persist. To explore the brain regions and neural mechanisms undergirding action anticipation, we compared distinct brain activation patterns involved in table tennis serve anticipation of expert table tennis athletes vs. non-experts by using both univariate analysis and multivoxel pattern analysis (MVPA). We collected functional magnetic resonance imaging data from 29 table tennis experts and 34 non-experts as they pressed a button to predict the trajectory of a ball in a table tennis serve video truncated at the moment of racket-ball contact vs. pressing any button while viewing a static image of the first video frame. MVPA was applied to assess whether it could accurately differentiate experts from non-experts. MVPA results indicated moderate accuracy (90.48%) for differentiating experts from non-experts. Brain regions contributing most to the differentiation included the left cerebellum, the vermis, the right middle temporal pole, the inferior parietal cortex, the bilateral paracentral lobule, and the left supplementary motor area. The findings suggest that brain regions associated with cognitive conflict monitoring and motor cognition contribute to the action anticipation ability of expert table tennis players.

fMRI evidence of movement familiarization effects on recognition memory in professional dancers.

Dual-process theories propose that recognition memory involves recollection and familiarity; however, the impact of motor expertise on memory recognition, especially the interplay between familiarity and recollection, is relatively unexplored. This functional magnetic resonance imaging study used videos of a dancer performing International Latin Dance Styles as stimuli to investigate memory recognition in professional dancers and matched controls. Participants observed and then reported whether they recognized dance actions, recording the level of confidence in their recollections, whereas blood-oxygen-level-dependent signals measured encoding and recognition processes. Professional dancers showed higher accuracy and hit rates for high-confidence judgments, whereas matched controls exhibited the opposite trend for low-confidence judgments. The right putamen and precentral gyrus showed group-based moderation effects, especially for high-confidence (vs. low-confidence) action recognition in professional dancers. During action recognition, the right superior temporal gyrus and insula showed increased activation for accurate recognition and high-confidence retrieval, particularly in matched controls. These findings highlighting enhanced action memory of professional dancers-evident in their heightened recognition confidence-not only supports the dual-processing model but also underscores the crucial role of expertise-driven familiarity in bolstering successful recollection. Additionally, they emphasize the involvement of the action observation network and frontal brain regions in facilitating detailed encoding linked to intention processing.

Influence of conflicting prior information on action anticipation in soccer players: an ERP study.

Objective: Prior probability information and visual kinematic information are essential for action anticipation in athletes. The aims of this study were to examine how conflicting prior information influences anticipatory judgment in athletes vs. non-athletes and to explore the underlying cognitive mechanisms. Methods: The aim of Experiment 1 was to determine the moment when prior information influenced action anticipation in athletes vs. non-athletes. To that end, 17 semi-elite soccer goalkeepers and 18 non-athletes received prior information about the probability of the direction that a player on a video would kick a ball into the goal. Participants then anticipated the trajectory of the ball when the action of the player's kick on the video was truncated at the moment the foot contacted the ball (time T) or one frame (T-1; 50 ms) or two frames (T-2; 100 ms) before the foot-ball contact. The aim of Experiment 2 was to elucidate the adaptive cognitive-motor behavior exhibited by highly trained soccer players at the moment when their anticipatory performance was most influenced by prior information. Experiment 2 included 27 different semi-elite soccer players with many years of experience as a goalkeeper and 27 different non-athletes. Participants anticipated the direction of the kick when the kinematic action of the kicker at the moment the anticipatory performance of the participants was most influenced by prior information (as determined in Experiment 1) was congruent, incongruent, or neutral. Action anticipation accuracy and response time were evaluated for both experiments, whereas event-related potential components N1, N2, and P3 were assessed only in Experiment 2. Results: The results of Experiment 1 showed that anticipatory accuracy was significantly higher among athletes than non-athletes and that anticipatory accuracy with directional information given was significantly higher than that when no prior information was given or when prior information without directional information was given (p < 0.001) for both T-1 (p's ≤ 0.034) and T-2 (p's < 0.001) occlusion points. In Experiment 2 using those two video occlusion times, the amplitude of the N1 component, which reflects selective attention to stimulus properties, was significantly higher in athletes than in non-athletes (p < 0.001). The amplitude of the N2 component, which has been associated with conflict monitoring, for the incongruent condition was significantly higher than that for both neutral (p < 0.001) and congruent (p < 0.001) conditions in athletes. Non-athletes exhibited no significant N2 amplitude differences for any prior information condition. Conclusion: Integrating prior information enhanced action anticipation in semi-elite soccer players, particularly 50 and 100 ms before the foot-ball contact. Semi-elite soccer players prioritized early selective attention and conflict monitoring of kinematic information, facilitating action anticipation using the prior information.

Brain mechanisms linking language processing and open motor skill training.

Given the discovery of a distributed language and motor functional network, surprisingly few studies have explored whether language processing is related to motor skill training. To address this issue, the present study used functional magnetic resonance imaging to compare whole-brain activation between nonexperts and experts in table tennis, an open skill sport in which players make rapid decisions in response to an ever-changing environment. Whole-brain activation was assessed in 30 expert table tennis players with more than 7 years' experience and 35 age-matched nonexpert college students while they performed both a size and a semantic judgment task of words presented on a monitor. Compared with nonexperts, expert table tennis players showed greater activation in the left middle occipital gyrus and right precuneus while judging the size of the words versus during baseline fixation. They also showed greater activation in the left lingual gyrus during the semantic judgment task versus during baseline fixation. Our findings indicate that the visual regions engaged in language processing are associated with open motor skill training.

Hand-related action words impair action anticipation in expert table tennis players: Behavioral and neural evidence.

Athletes extract kinematic information to anticipate action outcomes. Here, we examined the influence of linguistic information (experiment 1, 2) and its underlying neural correlates (experiment 2) on anticipatory judgment. Table tennis experts and novices remembered a hand- or leg-related verb or a spatial location while predicting the trajectory of a ball in a video occluded at the moment of the serve. Experiment 1 showed that predictions by experts were more accurate than novices, but experts' accuracy significantly decreased when hand-related words versus spatial locations were memorized. For nonoccluded videos with ball trajectories congruent or incongruent with server actions in experiment 2, remembering hand-related verbs shared cognitive resources with action anticipation only in experts, with heightened processing load (increased P3 amplitude) and more efficient conflict monitoring (decreased N2 amplitude) versus leg-related verbs. Thus, action anticipation required updating of motor representations facilitated by motor expertize but was also affected by effector-specific semantic representations of actions, suggesting a link from language to motor systems.

Enzyme-instructed hybrid nanogel/nanofiber oligopeptide hydrogel for localized protein delivery.

Enzyme-catalysis self-assembled oligopeptide hydrogel holds great interest in drug delivery, which has merits of biocompatibility, biodegradability and mild gelation conditions. However, its application for protein delivery is greatly limited by inevitable degradation of enzyme on the encapsulated proteins leading to loss of protein activity. Moreover, for the intracellularly acted proteins, cell membrane as a primary barrier hinders the transmembrane delivery of proteins. The internalized proteins also suffer from acidic and enzymatic degradation in endosomes and lysosomes. We herein develop a protease-manipulated hybrid nanogel/nanofiber hydrogel for localized delivery of intracellularly acted proteins. The embedded polymeric nanogels (CytoC/aNGs) preserve activity of cytochrome c (CytoC) that is an intracellular activator for cell apoptosis as a model protein against proteolysis, and do not affect the gelation properties of the protease-catalysis assembled hydrogels. The injectable hydrogel (CytoC/aNGs/Gel) serves as a reservoir to enhance intratumoral retention and realize sustainable release of CytoC/aNGs. The released CytoC/aNGs increase cellular uptake of CytoC and enhance its intracellular delivery to its target site, cytoplasm, resulting in favorable apoptosis-inducing and cytotoxic effects. We show that a single local administration of CytoC/aNGs/Gel efficiently inhibit the tumor growth in the breast tumor mouse model.

Improving the homologous recombination efficiency of Yarrowia lipolytica by grafting heterologous component from Saccharomyces cerevisiae.

The oleaginous non-conventional yeast Yarrowia lipolytica has enormous potential as a microbial platform for the synthesis of various bioproducts. However, while the model yeast Saccharomyces cerevisiae has very high homologous recombination (HR) efficiency, non-homologous end-joining is dominant in Y. lipolytica, and foreign genes are randomly inserted into the genome. Consequently, the low HR efficiency greatly restricts the genetic engineering of this yeast. In this study, RAD52, the key component of the HR machinery in S. cerevisiae, was grafted into Y. lipolytica to improve HR efficiency. The gene ade2, whose deletion can result in a brown colony phenotype, was used as the reporter gene for evaluating the HR efficiency. The HR efficiency of Y. lipolytica strains before and after integrating the ScRad52 gene was compared using insets with homology arms of different length. The results showed that the strategy could achieve gene targeting efficiencies of up to 95% with a homology arm length of 1000 bp, which was 6.5 times of the wildtype strain and 1.6 times of the traditionally used ku70 disruption strategy. This study will facilitate the further genetic engineering of Y. lipolytica to make it a more efficient cell factory for the production of value-added compounds.

Forkhead box protein C1 promotes cell proliferation and invasion in human cervical cancer.

Increasing evidence has demonstrated that aberrant forkhead box protein C1 (FOXC1) expression contributes to tumorigenesis in multiple types of malignant tumor. However, the clinical significance and biological roles of FOXC1 in cervical cancer remain unknown. The expression levels of FOXC1 were examined in human cervical cancer tissues and cells using reverse transcription­quantitative polymerase chain reaction, immunohistochemistry and western blotting. Furthermore, high FOXC1 expression was significantly associated with advanced clinical stages, a high degree of malignancy and a poor outcome. FOXC1 silencing inhibited cell growth and enhanced cell apoptosis. Knockdown of FOXC1 markedly suppressed cell migration and invasion in vitro, and resulted in downregulation of phosphorylated­RAC­α serine/threonine­protein kinase, proto­oncogene c­Myc and B­cell lymphoma 2. In conclusion, these data indicated that upregulation of FOXC1 contributed to the development of cervical cancer by increasing the growth and motility of the cervical cancer cells, thereby worsening the disease progression in these patients.

Contribution of underlying processes to improved visuospatial working memory associated with physical activity.

BACKGROUND: Working memory is critical for various cognitive processes and can be separated into two stages: short-term memory storage and manipulation processing. Although previous studies have demonstrated that increased physical activity (PA) improves working memory and that males outperform females on visuospatial working memory tasks, few studies have determined the contribution of the two underlying stages to the visuospatial working memory improvement associated with PA. Thus, the aims of the present study were to verify the relationship between physical activity and visuospatial working memory, determine whether one or both stages were affected by PA, and investigate any sex differences. METHODS: A total of 56 undergraduate students were recruited for this study. Their scores on the International Physical Activity Questionnaire (IPAQ) were used to separate them into either a lower PA (n = 26; IPAQ score ≤3,000 metabolic equivalent [MET]-min/week) or higher PA (n = 30; IPAQ score >3,000 MET-min/week) group. Participants were required to complete three tasks: a visuospatial working memory task, a task that examines the short-term memory storage stage, and a mental rotation task that examines the active manipulation stage. RESULTS: Participants in the higher PA group maintained similar accuracy but displayed significantly faster reaction times (RT) than those in the lower PA group on the visuospatial working memory and manipulation tasks. By contrast, no difference was observed between groups on the short-term memory storage task. In addition, no effects of sex were detected. DISCUSSION: Our results confirm that PA was positively to visuospatial working memory and that this positive relationship was associated with more rapid cognitive processing during the manipulation stage, with little or no relationship between PA and the memory storage stage of visuospatial working memory.

Knockdown of Nucleostemin in an ovarian cancer SKOV-3 cell line and its effects on cell malignancy.

Nucleostemin plays an essential role in the proliferation of some stem cells and cancer cells, but no research has been conducted to assess the link between Nucleostemin and ovarian cancer. To investigate the role of Nucleostemin in ovarian cancer tumorigenesis, we generated short hairpin (sh)RNA to knockdown the expression of the Nucleostemin gene in an ovarian cancer SKOV-3 cell line. We found that knockdown of this gene led to cell-cycle arrest, as well as to an increase in apoptosis. In addition, migration and invasion demonstrated significant inhibition in Nucleostemin-deficient cells. Furthermore, the knockdown of Nucleostemin dramatically suppressed xenograft progression in BALB/c nude mice. Our findings suggest that Nucleostemin is associated with malignancy in an ovarian cancer SKOV-3 cell line.