Movement-related potentials are task or end-effector dependent: evidence from a multifinger experiment

Abstract

In a number of recent studies, the specific sensitivity of movement-related EEG potentials toward experimental manipulations of motor tasks using the index finger as a primary end-effector is well documented. The major question in this study was whether different movement-related EEG components are primarily end-effector or task dependent. Accordingly, the experimental task (i.e., the rate of force development - a ratio of peak force to time-to-peak force) was systematically manipulated and the effects of this manipulation on movement-related potentials were examined while subjects used either the index, middle, ring or little finger. Significant effects observed in this study were due mainly to the sensitivity of movement-related potentials preceding movement onset (Bereit shafts potential and motor potential) toward the specific finger performing the task and the sensitivity of components accompanying the task (movement-monitoring potential) toward the rate of force development. In addition, both movement-related potentials preceding and accompanying movement significantly changed as a function of the finger performing the slow task (lower rate of force development) with maximum values observed for the ring finger and minimal values observed for the index finger. Behaviorally subjects were less accurate during slow tasks regardless of the finger performing the task. In contrast, the amplitude of neither early nor late components of movement-related potentials changed as a function of the finger performing the fast task (higher rate of force development). Overall, our results are consistent with the notion that the whole complex of movement-related EEG potentials reflect a combination of factors including the selection of corresponding general motor programs as reflected in the amplitude of potentials preceding movement and specific elements of the task including rate of force development as reflected in the amplitude of potentials accompanying movement execution.

Changes in Performance Monitoring During Sensorimotor Adaptation

“…This component is readily observed during a force generation task (Slobounov et al 2002) with a higher rate of force production corresponding with increased negativity and an EEG time series comparable to those observed in the present study. de Bruijn et al (2003) also observed a force production negativity after response onset in differing conditions, which led to their conducting separate analyses for the high and low force ranges to separate out the potential contributions from a MMP.…”

“…One possibility would be movement-monitoring potentials (MMPs) (Chiang et al 2004;Grunewald-Zuberbier and Grunewald 1978;Slobounov et al 1998Slobounov et al , 2000Slobounov et al , 2002, which are slow-moving negative potentials associated with preparation and execution of an action. The time course of this potential spans several seconds, with a rising negativity ϳ1,500 ms before movement onset, and a much larger ERP amplitude than the ERN that can persist for well over 1,000 ms (cf.…”

“…The time course of this potential spans several seconds, with a rising negativity ϳ1,500 ms before movement onset, and a much larger ERP amplitude than the ERN that can persist for well over 1,000 ms (cf. Chiang et al 2004;Slobounov et al 2000Slobounov et al , 2002.…”

Electrophysiological evidence for cortical plasticity with movement repetition

“…This component comprises the peak of the motor potential associated with movement execution and presumably reflects activity in M1 (Toma et al, 2002). M1 is of particular interest as there is strong evidence for its involvement in encoding force as well as movement kinematics (Kakei et al, 1999;Cramer et al, 2002;Slobounov et al, 2002), both relevant aspects in our ballistic power grip task. The observed pattern of an initial amplitude increase with subsequent decrease is particularly interesting as neural activity has been reported to generally decrease in M1 after movement repetition.…”

Towards a Biomarker of Motor Adaptation: Integration of Kinematic and Neural Factors

“…description of neural pathways) goes beyond the purpose of the present paper, we need to mention that the primary motor cortex (BA 4) also plays a primary role in the delivery of the motor command to the muscles, thus allowing a refined optimization of joint angles and the subtle tuning of torques [3], [18]. Electrically, a correlate is observed in the beta frequency band (18)(19)(20)(21)(22)(23)(24)(25), where some power decrease is found. Movement completion ends up in a sudden power increase in the beta band, also called event related synchronization (ERS) or beta rebound [12].…”