Effects of attention and precision of exerted force on beta range EEG-EMG synchronization during a maintained motor contraction task

Clin Neurophysiol. 2002 Jan;113(1):124-31. doi: 10.1016/s1388-2457(01)00722-2.

Abstract

Objective: The present study was aimed at investigating the effect of attention and precision level of exerted force on beta range EEG-EMG synchronization.

Methods: We simultaneously recorded cortical electrical activity (EEG) in a bipolar manner from the contralateral sensorimotor areas and surface electromyographic (EMG) activity from the flexor digitorum superficialis muscle in 10 healthy subjects during a maintained motor contraction task at 8% of the maximal voluntary contraction (MVC) force level. The coherence between oscillatory processes in the EEG and EMG was calculated. Three different conditions were investigated: (i) performing the task with high precision (HP); (ii) performing the task with high precision and simultaneously performing a mental arithmetic task (HPAT), i.e. attention was divided between the motor task and the mental arithmetic task; and (iii) performing the task with low precision (LP).

Results: We have found that the amount of beta range EEG-EMG synchronization decreases below the 95% confidence level when attention is divided between the motor task and the mental arithmetic task. The results also show that the frequency of beta range synchronization is higher with a higher level of precision but still lies within the beta frequency range (15-30 Hz).

Conclusions: The data indicate that beta range synchronization represents a state of the cortico-muscular network when attention is directed towards the motor task. The frequency of synchronization of this network is associated with, and possibly encodes, precision in force production.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Algorithms
  • Attention / physiology*
  • Beta Rhythm*
  • Electromyography*
  • Feedback / physiology
  • Female
  • Fingers / innervation
  • Fingers / physiology
  • Humans
  • Isometric Contraction / physiology
  • Male
  • Motor Cortex / physiology
  • Muscle, Skeletal / innervation
  • Muscle, Skeletal / physiology*
  • Psychomotor Performance / physiology*
  • Somatosensory Cortex / physiology