Cortical activity differs between position- and force-control knee extension tasks
- 392 Downloads
Neural control differs between position- and force-control tasks as evident from divergent effects of fatigue and pain. Unlike force-control tasks, position-control tasks focus on a postural goal to maintain a joint angle. Cortical involvement is suggested to be less during postural control, but whether this differs between position- and force-control paradigms remains unclear. Coherence estimates the functional communication between spatially distinct active regions within the cortex (cortico-cortical coherence; CCC) and between the cortex and muscles (corticomuscular coherence; CMC). We investigated whether cortical involvement differed between force-control and more posturally focused, position-control tasks. Seventeen adults performed position- and force-control knee extensor efforts at a submaximal load (10 % maximum voluntary contraction). Surface electromyography was recorded from the right knee extensor and flexor muscles and brain activity using electroencephalography (EEG). CCC and CMC in the beta (13–30 Hz) and gamma (30–45 Hz) frequency bands were calculated between combinations of intra- and inter-hemispheric pairs of electrodes, and between four EEG electrodes that approximated the left motor cortical area, and right knee extensor EMG, respectively. Differences in EEG power and muscle activity were also calculated. CCC was greater across distributed regions in the force-control task. Beta EEG power in the left hemisphere was higher for the position-control task. Although averaged CMC data differed between tasks, there was no task difference for individual CMC data. Muscle activity and force did not differ between tasks. The results demonstrate differential cortical contributions to control force- versus position-control tasks. This might contribute to differences in performance outcomes of these tasks that have been shown previously.
KeywordsCortico-cortical coherence Corticomuscular coherence Postural control Electroencephalography Electromyography Knee extensor muscles
Financial support was provided by the National Health and Medical Research Council of Australia (Research Fellowship [PH] ID401599 [KT] ID1009410; Project Grant—ID 569744). There was no conflict of interest.
- Bayraktaroglu Z, von Carlowitz-Ghori K, Losch F, Nolte G, Curio G, Nikulin VV (2011) Optimal imaging of cortico-muscular coherence through a novel regression technique based on multi-channel EEG and un-rectified EMG. Neuroimage 57:1059–1067. doi: 10.1016/j.neuroimage.2011.04.071 CrossRefPubMedGoogle Scholar
- Deeny SP, Hillman CH, Janelle CM, Hatfield BD (2003) Cortico-cortical communication and superior performance in skilled marksmen: an EEG coherence analysis. J Sport Exerc Psychol 25:188–204Google Scholar
- Halliday DM, Rosenberg JR, Amjad AM, Breeze P, Conway BA, Farmer SF (1995) A framework for the analysis of mixed time series/point process data—theory and application to the study of physiological tremor, single motor unit discharges and electromyograms. Prog Biophys Mol Biol 64:237–278. doi: 10.1016/s0079-6107(96)00009-0 CrossRefPubMedGoogle Scholar
- Nunez PL (eds) (1995) Mind, brain, and electroencephalography. In: Neocortical dynamics and human EEG rhythms. Oxford University Press, pp 133–194Google Scholar
- Pfurtscheller G, Lopes da Silva FH (eds) (1999) Functional meaning of event-related desynchronization (ERD) and synchronization (ERS). In: Handbook of electroencephalography and clinical neurophysiology, vol 6. Elsevier, Amsterdam, pp 51–65Google Scholar