Learning to tie well with others: bimanual versus intermanual performance of a highly practised skill

The effect of inherent and incidental constraints on bimanual force control in simulated Martian gravity

The ability to coordinate actions between the limbs is important for many operationally relevant tasks associated with space exploration. A future milestone in space exploration is sending humans to Mars. Therefore, an experiment was designed to examine the influence of inherent and incidental constraints on the stability characteristics associated with the bimanual control of force in simulated Martian gravity. A head-up tilt (HUT)/head-down tilt (HDT) paradigm was used to simulate gravity on Mars (22.3° HUT). Right limb dominant participants (N = 11) were required to rhythmically coordinate patterns of isometric forces in 1:1 in-phase and 1:2 multifrequency patterns by exerting force with their right and left limbs. Lissajous displays were provided to guide task performance. Participants performed 14 twenty-second practice trials at 90° HUT (Earth). Following a 30-min rest period, participants performed 2 test trials for each coordination pattern in both Earth and Mars conditions. Performance during the test trials were compared. Results indicated very effective temporal performance of the goal coordination tasks in both gravity conditions. However, results indicated differences associated with the production of force between Earth and Mars. In general, participants produced less force in simulated Martian gravity than in the Earth condition. In addition, force production was more harmonic in Martian gravity than Earth gravity for both limbs, indicating that less force distortions (adjustments, hesitations, and/or perturbations) occurred in the Mars condition than in the Earth condition. The force coherence analysis indicated significantly higher coherence in the 1:1 task than in the 1:2 task for all force frequency bands, with the highest level of coherence in the 1-4 Hz frequency band for both gravity conditions. High coherence in the 1-4 Hz frequency band is associated with a common neural drive that activates the two arms simultaneously and is consistent with the requirements of the two tasks. The results also support the notion that neural crosstalk stabilizes the performance of the 1:1 in-phase task. In addition, significantly higher coherence in the 8-12 Hz frequency bands were observed for the Earth condition than the Mars condition. Force coherence in the 8-12 Hz bands is associated with the processing of sensorimotor information, suggesting that participants were better at integrating visual, proprioceptive, and/or tactile feedback in Earth than for the Mars condition. Overall, the results indicate less neural interference in Martian gravity; however, participants appear to be more effective at using the Lissajous displays to guide performance under Earth's gravity.

The effect of inherent and incidental constraints on bimanual and social coordination

The current investigation was designed to examine the influence of inherent and incidental constraints on the stability characteristics associated with bimanual and social coordination. Individual participants (N = 9) and pairs of participants (N = 18, 9 pairs) were required to rhythmically coordinate patterns of isometric forces in 1:1 in-phase and 1:2 multi-frequency patterns by exerting force with their right and left limbs. Lissajous information was provided to guide performance. Participants performed 13 practice trials and 1 test trial per pattern. On the test trial, muscle activity from the triceps brachii muscles of each arm was recorded. EMG-EMG coherence between the two EMG signals was calculated using wavelet coherence. The behavioral data indicated that individual participants performed the 1:1 in-phase pattern more accurately and with less variability than paired participants. The EMG coherence analysis indicated significantly higher coherence for individual participants than for the paired participants during the 1:1 in-phase pattern, whereas no differences were observed between groups for the 1:2 coordination pattern. The results of the current investigation support the notion that neural crosstalk can stabilize 1:1 in-phase coordination when contralateral and ipsilateral signals are integrated via the neuromuscular linkage between two effectors.

Using Communication to Modulate Neural Synchronization in Teams

Throughout training and team performance, teams may be assessed based on their communication patterns to identify which behaviors contributed to the team’s performance; however, this process of establishing meaning in communication is burdensome and time consuming despite the low monetary cost. A current topic in team research is developing covert measures, which are easier to analyze in real-time, to identify team processes as they occur during team performance; however, little is known about how overt and covert measures of team process relate to one another. In this study, we investigated the relationship between overt (communication) and covert (neural) measures of team process by manipulating the interaction partner (participant or experimenter) team members worked with and the type of task (decision-making or action-based) teams performed to assess their effects on team neural synchronization (measured as neurodynamic entropy) and communication (measured as both flow and content). The results indicated that the type of task affected how the teams structured their communication but had unpredictable effects on the neural synchronization of the team when averaged across the task session. The interaction partner did not affect team neural synchronization when averaged. However, there were significant relationships when communication and neural processes were examined over time between the neurodynamic entropy and the communication flow time series due to both the type of task and the interaction partner. Specifically, significant relationships across time were observed when participants were interacting with the other participant, during the second task trial, and across different regions of the cortex depending on the type of task being performed. The findings from the time series analyses suggest that factors that are previously known to affect communication (interaction partner and task type) also structure the relationship between team communication and neural synchronization—cross-level effects—but only when examined across time. Future research should consider these factors when developing new conceptualizations of team process measurement for measuring team performance over time.

Accessing interpersonal and intrapersonal coordination dynamics

Both intrapersonal and interpersonal coordination dynamics have traditionally been investigated using relative phase patterns of in-phase (ϕ = 0°) and/or anti-phase (ϕ = 180°). Numerous investigations have demonstrated that coordination tasks that require other relative phase patterns (e.g., 90°) are difficult or near impossible to perform without extended practice. Recent findings, however, have demonstrated that an individual can produce a wide range of intrapersonal bimanual patterns within a few minutes of practice when provided integrated feedback. The present experiment was designed to directly compare intra- and interpersonal coordination performance and variability when provided Lissajous feedback or pacing metronome. Single participants (N = 12) and pairs of participants (N = 24, 12 pairs) were required to produce relative phase patterns between 0° and 180° in 30° increments using either pacing metronomes or Lissajous displays. The Lissajous displays involved a goal template and a cursor providing integrated feedback regarding the position of the two effectors. The results indicated both single and pairs of participants could effectively produce a large range of coordination patterns that typically act as repellers after only 6 min of practice when provided integrated feedback. However, single participants performed the in-phase coordination pattern more accurately and with less variability than paired participants, regardless of the feedback condition. These results suggest an advantage for intrapersonal coordination when performing in-phase coordination, possibly due to the stabilizing effect occurring via the neuro-muscular linkage between effectors.

Communication of Visual and Auditory Information and The Coordination of Team Task Performance

Due to lack of visual or auditory perceptual information, many tasks require interpersonal coordination and teaming. Dyadic verbal and/or auditory communication typically results in the two people becoming informationally coupled. This experiment examined coupling by using a two-person remote navigation task where one participant blindly drove a remote-controlled car while another participant provided auditory, visual, or a combination of both cues (bimodal). Under these conditions, we evaluated performance using easy, moderate, and hard task difficulties. We predicted that the visual condition would have higher performance measures overall, and the bimodal condition would have higher performance as difficulty increased. Results indicated that visual coupling performs better overall compared to auditory coupling and that bimodal coupling showed increased performance as task difficulty went from moderate to hard. When auditory coupling occurs, the frequency at which teams communicate affects performance— the faster teams spoke, the better they performed, even with visual communication available.

Understanding and Modeling Teams As Dynamical Systems

By its very nature, much of teamwork is distributed across, and not stored within, interdependent people working toward a common goal. In this light, we advocate a systems perspective on teamwork that is based on general coordination principles that are not limited to cognitive, motor, and physiological levels of explanation within the individual. In this article, we present a framework for understanding and modeling teams as dynamical systems and review our empirical findings on teams as dynamical systems. We proceed by (a) considering the question of why study teams as dynamical systems, (b) considering the meaning of dynamical systems concepts (attractors; perturbation; synchronization; fractals) in the context of teams, (c) describe empirical studies of team coordination dynamics at the perceptual-motor, cognitive-behavioral, and cognitive-neurophysiological levels of analysis, and (d) consider the theoretical and practical implications of this approach, including new kinds of explanations of human performance and real-time analysis and performance modeling. Throughout our discussion of the topics we consider how to describe teamwork using equations and/or modeling techniques that describe the dynamics. Finally, we consider what dynamical equations and models do and do not tell us about human performance in teams and suggest future research directions in this area.

Cross-Level Effects Between Neurophysiology and Communication During Team Training

OBJECTIVE

We investigated cross-level effects, which are concurrent changes across neural and cognitive-behavioral levels of analysis as teams interact, between neurophysiology and team communication variables under variations in team training.

BACKGROUND

When people work together as a team, they develop neural, cognitive, and behavioral patterns that they would not develop individually. It is currently unknown whether these patterns are associated with each other in the form of cross-level effects.

METHOD

Team-level neurophysiology and latent semantic analysis communication data were collected from submarine teams in a training simulation. We analyzed whether (a) both neural and communication variables change together in response to changes in training segments (briefing, scenario, or debriefing), (b) neural and communication variables mutually discriminate teams of different experience levels, and (c) peak cross-correlations between neural and communication variables identify how the levels are linked.

RESULTS

Changes in training segment led to changes in both neural and communication variables, neural and communication variables mutually discriminated between teams of different experience levels, and peak cross-correlations indicated that changes in communication precede changes in neural patterns in more experienced teams.

CONCLUSION

Cross-level effects suggest that teamwork is not reducible to a fundamental level of analysis and that training effects are spread out across neural and cognitive-behavioral levels of analysis. Cross-level effects are important to consider for theories of team performance and practical aspects of team training.

APPLICATION

Cross-level effects suggest that measurements could be taken at one level (e.g., neural) to assess team experience (or skill) on another level (e.g., cognitive-behavioral).