Physiological Reactions and Performance Parameters in Single-Player and Competitive Arm Rehabilitation Game: A Pilot Study

Abstract BackgroundInterpersonal rehabilitation games, compared to single-player games, enhance motivation and intensity level. Usually, it is very difficult to limit the use of the system to pairs of impaired patients who have a similar skill level. Thus, such games must be dynamically adapted so that two players with different abilities can play together. Current algorithms are based only on game performance parameters (e.g., score). In addition, these studies do not include active robotic devices, so the parameters related to the level of robot assistance are not usually included in these studies. This means that the adaptation methods are entirely based on modifying aspects of the game. The aim of this article, is to study the effect that game modality and robot parameters that can be affected by the level of robot assistance (e.g., velocity, reaction time) have on the stress level of the subjects.MethodsThe pilot study has involved 10 unimpaired participants (5 pairs). Each subject sat in front of a robotic rehabilitation platform and grasped the end-effector of the robot with their dominant hand and played two kinds of therapy games: i) a single-player game in 3 difficulty modes; and ii) a competitive game. Robot and game parameters and subject's physiological responses were recording during the therapy games.ResultsThe intensity level in the most difficult single-player game mode, is almost equal to the one of the competitive mode (p=1.0). The stress perceived subjectively by participants increases with intensity. They indicate that the stress level in competitive mode is equal or somewhat greater than in high difficulty mode. On the other hand, physiological data suggest that it is somewhat lower in the competitive mode. Therefore, in this mode participants think they experience a higher stress level than they are actually experiencing. In addition, physiological responses show differences between intensity levels, and they also have a good correlation with the measured robot parameters.ConclusionResults show that, comparing competitive game with the single-player high-difficulty game, a similar intensity level is remarkable. However, the competitive game increase the stress level to a lesser extent. In addition, feedback from participants suggests that it is necessary to keep a certain stress level to make the activity more challenging, and therefore be more engaging and rewarding.