Utilization of cues in action anticipation in table tennis players.

By manipulating the congruency between body kinematics and subsequent ball trajectory, this study investigated the anticipation capabilities of regional-level, college-level, and novice table tennis players using a full video simulation occluder paradigm. Participants watched footage containing congruent, incongruent, or no ball trajectory information, to predict the landing point of the ball. They were required to choose between two potential locations to make their prediction. Percent accuracy and relevant indexes (d-prime, criterion, effect size) were calculated for each condition. Results indicated that experienced table tennis players (both regional and college players) were superior to novices in the ability to anticipate ball trajectory using kinematic information, but no difference was found between regional-level and college-level players. The findings of this study further demonstrate the superior anticipation ability of experienced table tennis players. Furthermore, the present result suggests that there may be a certain "baseline" level of motor experience in racquet sports for effective action anticipation, while the addition of further motor experience does not appear to assist direction anticipation.

Effect of Self-Controlled Practice on Neuro-Cortical Dynamics During the Processing of Visual Performance Feedback.

Evidence has accumulated that learners participating in self-controlled practice can both acquire skills and process task-relevant information more effectively than those participating in externally controlled practice. However, the impact of self-controlled practice on neuro-cognitive information processing during visual performance-related feedback has received limited investigation. We expected that individuals participating in self-controlled practice would exhibit elevated neuro-cognitive information processing, as assessed via electroencephalography (EEG), compared with those engaged with externally controlled practice. Participants practiced a golf-putting task under self-controlled or externally controlled (yoked) conditions while EEG data were recorded. Results indicated that EEG theta power was maintained at an elevated level during the feedback period in the self-controlled group relative to the yoked group. The yoked group did not display increases in theta power until the time at which the ball stopped. Both groups displayed similar improvement over the course of the experiment. Correlational analyses revealed that performance improvement within each group was related differently to EEG theta power. Specifically, the self-controlled group displayed positive relationships between theta power and performance improvement, while the yoked group displayed negative relationships. These results have implications regarding the relative effectiveness of self-controlled and externally controlled practice and the instances in which they may provide the most benefit.

The relationship between Gulf War Illness symptom severity and heart rate variability: A pilot study.

INTRODUCTION: Gulf War Illness (GWI) is a chronic multisymptom illness affecting 250,000+ veterans of the '90-'91 Gulf War which remains under-explored in terms of its physiological characteristics. We investigated whether subjective GWI symptom severity scores were related to objective measures of autonomic nervous system activity. METHODS: We estimated activity in the two major branches of the autonomic nervous system (the parasympathetic nervous system [PNS] and the sympathetic nervous system [SNS]) via metrics of heart rate variability in a sample of Veterans who met established criteria for GWI with varying degrees of self-reported symptom severity. We hypothesized that subjective symptom severity scores would be inversely related to PNS activity and positively related to SNS activity. RESULTS: Significant negative relationships were observed between the root mean square of successive differences of beat-to-beat intervals (a measure of PNS activity) and symptom severity, both overall and across specific GWI symptom categories (sp. fatigue [r = -0.574], gastrointestinal [r = -0.544]). Furthermore, significant positive relationships were observed between the cardiac sympathetic index and symptom severity, both overall and across specific symptom categories (sp. cognitive [r = 0.721], fatigue [r = 0.560], gastrointestinal [r = 0.694], skin [r = 0.686]). CONCLUSIONS: Metrics of PNS activation revealed a negative relationship with self-reported symptom severity, while metrics of SNS activation revealed a positive relationship. The present results improve our understanding of the physiology of GWI and provide a new window from which to consider this medically unexplained illness.

Self-Controlled Practice to Achieve Neuro-Cognitive Engagement: Underlying Brain Processes to Enhance Cognitive-Motor Learning and Performance.

While self-controlled practice has been shown to be an effective practice methodology, the neuro-cognitive correlates of its effectiveness are unclear. We investigated whether learners participating in self-controlled practice exhibit increased neuro-cognitive engagement compared to externally controlled practice. Two groups (self-controlled and yoked) of 16 participants practiced and performed a golf putting task over 3 days. Working memory engagement, central executive activity, and cortical activation were assessed via electroencephalography as indicators of neuro-cognitive engagement. The self-controlled group exhibited more consistent working memory engagement, and greater central executive activity, compared to the yoked group during practice. Relationships were also observed between neuro-cognitive engagement during self-controlled practice and performance improvement, indicating that self-controlled practice uniquely benefitted from increased neuro-cognitive engagement.

Changes in Mental Workload and Motor Performance Throughout Multiple Practice Sessions Under Various Levels of Task Difficulty.

The allocation of mental workload is critical to maintain cognitive-motor performance under various demands. While mental workload has been investigated during performance, limited efforts have examined it during cognitive-motor learning, while none have concurrently manipulated task difficulty. It is reasonable to surmise that the difficulty level at which a skill is practiced would impact the rate of skill acquisition and also the rate at which mental workload is reduced during learning (relatively slowed for challenging compared to easier tasks). This study aimed to monitor mental workload by assessing cortical dynamics during a task practiced under two difficulty levels over four days while perceived task demand, performance, and electroencephalography (EEG) were collected. As expected, self-reported mental workload was reduced, greater working memory engagement via EEG theta synchrony was observed, and reduced cortical activation, as indexed by progressive EEG alpha synchrony was detected during practice. Task difficulty was positively related to the magnitude of alpha desynchrony and accompanied by elevations in the theta-alpha ratio. Counter to expectation, the absence of an interaction between task difficulty and practice days for both theta and alpha power indicates that the refinement of mental processes throughout learning occurred at a comparable rate for both levels of difficulty. Thus, the assessment of brain dynamics was sensitive to the rate of change of cognitive workload with practice, but not to the degree of difficulty. Future work should consider a broader range of task demands and additional measures of brain processes to further assess this phenomenon.

Combined assessment of attentional reserve and cognitive-motor effort under various levels of challenge with a dry EEG system.

A novel ERP approach was proposed to index variations in mental workload, particularly in attentional reserve, which is complementary to EEG spectral content thought to reflect mental effort. To our knowledge, no study has assessed mental effort and attentional reserve simultaneously in EEG gel-based and, importantly, dry systems, which are particularly well suited for real-world settings. Therefore, by systematically considering ERP, EEG spectral, and importantly the combination of both, this study examined if a small set of dry EEG electrodes could detect changes in both spectral and ERP metrics to assess the mental workload under various challenges with a similar fidelity to their gel-based counterparts in a laboratory setting. By employing both EEG gel-based and dry systems, the ERP and spectral markers were computed while participants executed a visuomotor task under three levels of challenge. For both EEG systems, more challenging levels of difficulty were associated with concomitant changes in ERP amplitude, and spectral power reflected a reduction of the attentional reserve and an increase in cognitive-motor effort, respectively. Those variations in attentional reserve and cognitive-motor effort collectively indexed mental workload with nearly identical fidelity for both gel-based and dry EEG systems. These findings promise to assess the mental workload in situations where the use of dry EEG systems could be advantageously employed to examine human cognitive-motor performance.

Valence and arousal of emotional stimuli impact cognitive-motor performance in an oddball task.

It is widely recognized that emotions impact an individual's ability to perform in a given task. However, little is known about how emotion impacts the various aspects of cognitive -motor performance. We recorded event-related potentials (ERPs) and chronometric responses from twenty-six participants while they performed a cognitive-motor oddball task in regard to four categories of emotional stimuli (high-arousing positive-valence, low-arousing positive-valence, high-arousing negative-valence, and low-arousing negative-valence) as "deviant" stimuli. Six chronometric responses (reaction time, press time, return time, choice time, movement time, and total time) and three ERP components (P2, N2 and late positive potential) were measured. Results indicated that reaction time was significantly affected by the presentation of emotional stimuli. Also observed was a negative relationship between N2 amplitude and elements of performance featuring reaction time in the low-arousing positive-valence condition. This study provides further evidence that emotional stimuli influence cognitive-motor performance in a specific manner.

Empirical evidence for the relationship between cognitive workload and attentional reserve.

While the concepts of cognitive workload and attentional reserve have been thought to have an inverse relationship for some time, such a relationship has never been empirically tested. This was the purpose of the present study. Aspects of the electroencephalogram were used to assess both cognitive workload and attentional reserve. Specifically, spectral measures of cortical activation were used to assess cognitive workload, while amplitudes of the event-related potential from the presentation of unattended "novel" sounds were used to assess attentional reserve. The relationship between these two families of measures was assessed using canonical correlation. Twenty-seven participants performed a flight simulator task under three levels of challenge. Verification of manipulation was performed using self-report measures of task demand, objective task performance, and heart rate variability using electrocardiography. Results revealed a strong, negative relationship between the spectral measures of cortical activation, believed to be representative of cognitive workload, and ERP amplitudes, believed to be representative of attentional reserve. This finding provides support for the theoretical and intuitive notion that cognitive workload and attentional reserve are inversely related. The practical implications of this result include improved state classification using advanced machine learning techniques, enhanced personnel selection/recruitment/placement, and augmented learning/training.

Decomposing valence intensity effects in disgusting and fearful stimuli: an event-related potential study.

We are sensitive to valence intensity in negative emotional stimuli, but not in positive emotional stimuli, a phenomenon known as the valence intensity effect. However, whether this valence intensity effect is processed similarly within different negative stimuli, e.g., fear-inducing and disgust-inducing, remains unclear. In the present study, we investigated whether the valence intensity effects for fearful and disgusting stimuli were perceived in a unique way by using event-related potentials (ERPs). Electroencephalogram was recorded from 22 participants as they performed a standard/deviant categorization task using extremely disgusting pictures, moderately disgusting pictures, extremely fearful pictures, moderately fearful pictures, and neutral pictures. The ERP analysis revealed that the extremely fearful stimuli elicited a larger amplitude N2 than moderately fearful stimuli, whereas the extremely disgusting stimuli elicited a smaller amplitude late positive component than moderately disgusting stimuli. This study is the first to provide evidence that fear and disgust may have different valence intensity effects, which was revealed at early attention allocation stages for fearful stimuli and at late emotional evaluation stages for disgusting stimuli.

Brain biomarkers based assessment of cognitive workload in pilots under various task demands.

Cognitive workload is an important element of cognitive-motor performance such as that exhibited during the piloting of an aircraft. Namely, an increase in task demands on the pilot can elevate cognitive information processing and, thus, the risk of human error. As such, there is a need to develop methods that reliably assess mental workload in pilots within operational settings. The present study contributes to this research goal by identifying physiological and brain biomarkers of cognitive workload and attentional reserve during a simulated aircraft piloting task under three progressive levels of challenge. A newly developed experimental method was employed by which electroencephalography (EEG) was acquired via a dry (i.e., gel-free sensors) system using few scalp sites. Self-reported responses to surveys and piloting performance indicators were analyzed. The findings revealed that as the challenge (task demands) increased, the perceived mental load increased, attentional reserve was attenuated, and task performance decreased. Such an increase in task demands was also reflected by changes in heart rate variability (HRV), as well as in the amplitude of the P300 component of event-related potentials to auditory probes, and in the spectral power of specific EEG frequency bands. This work provides a first step towards a long-term goal to develop a composite system of biomarkers for real-time cognitive workload assessment and state assessment of pilots in operational settings.