Functional stages in the formation of human long-term motor memory.
ABSTRACT Previous research has demonstrated that the primate CNS has the ability to learn and store multiple and conflicting visuo-motor maps. Here we studied the ability of human subjects to learn to make reaching movements while interacting with one of two conflicting mechanical environments as produced by a robotic manipulandum. We demonstrate that two motor maps may be learned and retained, but only if the training sessions in the tasks are separated by an interval of approximately 5 hr. If the interval is shorter, learning of the second map begins with an internal model appropriate for the first task and performance in the second task is significantly impaired. Analysis of the after-effects suggests that with a short temporal distance, learning of the second task leads to an unlearning of the internal model for the first. With the longer temporal distance, learning of the second task starts with an unbiased internal model, and performance approaches that of naives. Furthermore, the memory of the consolidated skill lasts for at least 5 months after training. These results argue for a distinct change in the state of resistance of motor memory (to disruption) within a few hours after acquisition. We suggest that motor practice results in memories that have at least two functional components: soon after completion of practice, one component fades while another is strengthened. A further experiment suggests that the hypothetical first stage is not merely a gateway to long-term memory, but also temporary storage for items of information, whether new or old, for use in the near-term. Our results raise the possibility that there are distinct neuronal mechanisms for representation of the two functional stages of motor memory.
SourceAvailable from: Juan-Carlos Quintana-Duque
Conference Paper: Sportinformatik 2012 ProceedingsSportinformatik 2012. Symposium der Sektion Sportinformatik der Deutschen Vereinigung für Sportwissenschaft, Konstanz, Germany; 09/2012
Conference Paper: Sportinformatik 2012 extended abstractsSportinformatik 2012. Symposium der Sektion Sportinformatik der Deutschen Vereinigung für Sportwissenschaft, Konstanz, Germany; 09/2012
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ABSTRACT: Drive-by-wire technology enables braking and accelerating by hand. Operating the hand brake is essentially a multi-finger force synergy task. Few studies have been conducted on precision grip involving all the fingers of one hand or both hands when manipulating an object of irregular shape. This study examined the effects of target force level, numbers of hands used in the task, grip posture, grip duration, and training on hand-operated control device operation. Age and gender effects have also been investigated. The results showed that target force level, hand used in the task, grip posture and grip duration had the significant impact on the grip force coordination. With the development of digital human modeling and digital human simulation, analysis tools that facilitate prediction of variations in human performance and vehicle control based on modern design conditions can be useful for future designers before first physical mockups.The 3rd International Conference on Applied Human Factors and Ergonomics (AHFE); 01/2010