Social feedback: determination of social learning

Cross-feedback with Partner Contributes to Performance Accuracy in Finger-tapping Rhythm Synchronization between One Leader and Two Followers

As observed in musical ensembles, people synchronize with a leader together with other people. This study aimed to investigate whether interdependency with a partner improves performance accuracy in rhythm synchronization with the leader. Participants performed a synchronization task via auditory signal by finger tapping in which two followers simultaneously synchronized with a leader: an isochronous metronome or a human leader with or without feedback from the followers. This task was conducted with and without cross-feedback (CFB) between the followers. The followers’ weak mutual tempo tracking via the CFB and the followers’ strong tempo tracking to the leader improved the tempo stability. Additionally, because the interdependency between the followers was weaker than the followers’ dependency on the human leader, the CFB did not enlarge the synchronization error between the human leader and the followers, which occurred in synchronization with the metronome. Thus, the CFB between the followers contributed to accuracy in synchronization with the human leader. The results suggest that in ensembles, players should strongly attend to the leader and should attempt to be less conscious of partners to maintain the appropriate balance between influences from the leader and partners.

An Experimental Study of Individualized Learning/Instruction in Copying, Tracking, and Handwriting Based on Feedback Principles

During the last 10 to 15 yr. the stressing of individualized instructions has caused a reorganization of some schools, curricula, and instructional methods. Different theoretical approaches have been used for developing individualized instruction programmes in reading, spelling, and writing. The present experimental study of individualized instruction in copying, tracing, tracking, and handwriting was based on theoretical feedback principles. Close relationships between visuo-motor ability, copying, tracing, tracking, and writing performances were hypothesized and so were the main effects of the experimental programme with concern to the educational, psychomotor skills in question. In general, the predictions were confirmed by data in the present study in which 36 third-graders participated. Some additional information was presented, e.g., significant interaction between the experimental programme and subjects' writing skills was found for tracing only.

Effects of Delay of Feedback and Intermittency of Feedback in Compensatory Tracking

Previous research established both delay and intermittency of feedback as two major sources of temporal perturbation in a compensatory tracking task. Tracking accuracy decreased as a function of an increase in both feedback conditions. Also, disruption of both types of feedback showed similar deterioration of the task as observed in separate studies. The present study was designed to compare effects of differential severity of delay and intermirtency of feedback on identical magnitudes of temporal perturbation on a compensatory tracking task. Time intervals of 0.0, 0.2, 0.4, 0.6, 0.8, 1.0, and 1.5 sec. were used for both conditions. After 10 trials at 0.0 sec. as practice, each subject was tested under each of the perturbation conditions with 6 trials for each of the 6 intervals, making a total of 12 experimental trials. Delay of feedback affected tracking significantly more than intermittency of feedback at all magnitudes. Normal feedback of zero perturbation was the best condition for task performance. In both feedback conditions, tracking deteriorated as a function of increased magnitudes of disruption of feedback. Learning occurred in the two experimental conditions but not in the condition of normal feedback.

Social-physiological compliance as a determinant of team performance

A cybernetic model of behavior predicts that team performance may depend on physiological compliance among participants. This laboratory study tested if compliance in electrodermal activity (EDA), heart rate or breathing in two-person teams (N=16) was predictive of team performance or coordination in a continuous tracking task simulating teleoperation. Visual contact among participants was manipulated. Physiological compliance was scored with weighted coherence and cross correlation. Separate multiple regression analyses revealed that the task completion time was predicted by coherence measures for EDA and heart, but only at a trend level for breathing. Task completion time was also predicted by heart cross correlation. Team tracking error was predicted by coherence measures for EDA, heart and breathing, and also heart cross correlation. While social-visual contact did not have an impact, physiological compliance was predictive of improved performance, with coherence robust over all three physiological measures. Heart cross correlation showed the strongest predictive relationships. These results provide evidence that physiological compliance among team members may benefit team performance. While further study is needed, physiological compliance may someday provide a needed tool for the study of team work, and an objective means to guide the ergonomic design of complex sociotechnical systems requiring a high degree of team proficiency.

Work organization and ergonomics

This paper examines the impact of sociotechnical and business trends on work organization and ergonomics. This analysis is performed with the use of Balance Theory (Smith and Carayon-Sainfort, Int. J. Ind. Ergon. 1989, 4, 67-79). The impact on work organization and the work system of the following sociotechnical and business trends is discussed: re-structuring and re-organizing of companies, new forms of work organization, workforce diversity, and information and communication technology. An expansion of Balance Theory, from the design of work systems to the design of organizations, is discussed. Finally, the issue of change is examined. Several elements and methods are discussed for the design of change processes.

Cooperative tapping: time control under different feedback conditions

The same isochronous tone sequence was presented simultaneously to two mutually isolated subjects. In half the trials, accentuation in this sequence was accomplished by doubling the duration of the first and then of every fourth tone; in the other half, by doubling the frequency of those tones. The subjects' task was to follow the rhythm of the resulting four-tone patterns by finger tapping to tone onsets. There were four auditory feedback (FB) conditions: (1) no FB; (2) FB from the subject's own motor responses; (3) "alien" FB from the motor responses of the other pair member who, in turn, was listening to FB from his/her own tapping; (4) mutually "crossed" FB, where each pair member listened to FB from the tapping of the other. Tap onsets regularly preceded stimulus onsets. The observed order of the amount of this anticipation (from least to greatest) was: (1) own FB, (2) no FB, (3) alien FB, and (4) crossed FB. No mutual dynamic influence between simultaneously performing subjects was detected. Anticipation was more pronounced for sequences that were accentuated by frequency rather than by duration changes. The type of accent also influenced timing of intertap intervals in the rhythmic patterns. For the frequency accent, regular timing was produced, whereas for the durational accent, shortening of the second and lengthening of the fourth (the last) intertap interval were observed. The presence and source of feedback as well as the character of accentuation are therefore relevant factors in the timing of auditorally controlled rhythmic motor behavior.

Effects of intermittency of feedback on a compensatory tracking task

Target intermittence in tracking has been studied as frequency of target presentation at various time intervals. Task efficiency increased as a function of increased frequency of target display in open-loop tracking tasks, where the steady state of presentation resulted in the best performance. The present study examined effects of feedback intermittency in compensatory tracking as a major source of disruption of the motor-sensory feedback process in the closed-loop tracking system. Feedback intermittency is defined as the feedback of momentary sampling of the difference between target movements and the operator's control motion for specified time lengths before being displayed to him in a continuous tracking task. With a random wave pattern of 9.76 cpm, 7 magnitudes of 0.0, 0.2, 0.4, 0.6, 0.8, 1.0, and 1.5 sec. were used to represent various levels of feedback intermittency. Task efficiency decreased as a function of increased magnitudes of intermittency. Results are discussed relative to the difference between target intermittence and feedback intermittency and their effects on different tracking tasks. The findings also establish the concept of feedback intermittency as a disturbing factor in compensatory tracking in degrading the operator's performance.