Adaptation to Delayed Force Perturbations in Reaching Movements

• Published in: PloS one Vol. 5; no. 8; p. e12128
• Main Authors: Levy, Noa, Pressman, Assaf, Mussa-Ivaldi, Ferdinando A., Karniel, Amir
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 11.08.2010; Public Library of Science (PLoS)
• Subjects: Adaptation; Adaptation, Physiological - physiology; Adolescent; Adult; Biomechanical Phenomena; Biomedical engineering; Brain; Brain - physiology; Brain research; Commands; Comparative analysis; Feedback; Humans; Information management; Information systems; Kinematics; Movement - physiology; Neuroscience/Behavioral Neuroscience; Neuroscience/Cognitive Neuroscience; Neuroscience/Experimental Psychology; Neuroscience/Motor Systems; Physiology/Cognitive Neuroscience; Physiology/Motor Systems; Time Factors; Velocity; Windows (intervals); Young Adult; Chicago Illinois; Israel; United States > US; Illinois
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0012128

Adaptation to deterministic force perturbations during reaching movements was extensively studied in the last few decades. Here, we use this methodology to explore the ability of the brain to adapt to a delayed velocity-dependent force field. Two groups of subjects preformed a standard reaching experiment under a velocity dependent force field. The force was either immediately proportional to the current velocity (Control) or lagged it by 50 ms (Test). The results demonstrate clear adaptation to the delayed force perturbations. Deviations from a straight line during catch trials were shifted in time compared to post-adaptation to a non-delayed velocity dependent field (Control), indicating expectation to the delayed force field. Adaptation to force fields is considered to be a process in which the motor system predicts the forces to be expected based on the state that a limb will assume in response to motor commands. This study demonstrates for the first time that the temporal window of this prediction needs not to be fixed. This is relevant to the ability of the adaptive mechanisms to compensate for variability in the transmission of information across the sensory-motor system.