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Human cortical traveling waves: dynamical properties and correlations with responses.

Patten TM, Rennie CJ, Robinson PA, Gong P - PLoS ONE (2012)

Bottom Line: The spatiotemporal behavior of human EEG oscillations is investigated.Traveling waves in the alpha and theta ranges are found to be common in both prestimulus and poststimulus EEG activity.The dynamical properties of these waves, including their speeds, directions, and durations, are systematically characterized for the first time, and the results show that there are significant changes of prestimulus spontaneous waves in the presence of an external stimulus.

View Article: PubMed Central - PubMed

Affiliation: School of Physics, University of Sydney, Sydney, New South Wales, Australia.

ABSTRACT
The spatiotemporal behavior of human EEG oscillations is investigated. Traveling waves in the alpha and theta ranges are found to be common in both prestimulus and poststimulus EEG activity. The dynamical properties of these waves, including their speeds, directions, and durations, are systematically characterized for the first time, and the results show that there are significant changes of prestimulus spontaneous waves in the presence of an external stimulus. Furthermore, the functional relevance of these waves is examined by studying how they are correlated with reaction times on a single trial basis; prestimulus alpha waves traveling in the frontal-to-occipital direction are found to be most correlated to reaction speeds. These findings suggest that propagating waves of brain oscillations might be involved in mediating long-range interactions between widely distributed parts of human cortex.

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Phase differences along the chain of electrodes, including F4, FC4, C4, CP4, P4, and O2, at different times with step size of 6 ms.Red circles are the calculated phases for EEG signals with the average mastoid reference, black ones for EEG signals with an average reference; this result indicates that these phase differences do not sensitively depend on the reference channel.
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pone-0038392-g005: Phase differences along the chain of electrodes, including F4, FC4, C4, CP4, P4, and O2, at different times with step size of 6 ms.Red circles are the calculated phases for EEG signals with the average mastoid reference, black ones for EEG signals with an average reference; this result indicates that these phase differences do not sensitively depend on the reference channel.

Mentions: To calculate phases for the prominent alpha and theta oscillations, we adjusted the scale of the wavelet to make it centered at the peaks of these oscillations accordingly, which were determined individually on the basis of the above time-frequency analysis. After obtaining the phases of these oscillations, we then calculated phase differences for the electrodes along each of the three chains shown in Fig. 1. We found that there were significant time intervals during which there were progressive phase shifts along these chains. Figure 4 shows such a typical example for electrodes along the F4 to O2 chain with phase shifts in F-to-O direction, and Fig. 5 for phase shifts in O-to-F direction. The phase shift over the electrodes was then fitted to get a straight line.


Human cortical traveling waves: dynamical properties and correlations with responses.

Patten TM, Rennie CJ, Robinson PA, Gong P - PLoS ONE (2012)

Phase differences along the chain of electrodes, including F4, FC4, C4, CP4, P4, and O2, at different times with step size of 6 ms.Red circles are the calculated phases for EEG signals with the average mastoid reference, black ones for EEG signals with an average reference; this result indicates that these phase differences do not sensitively depend on the reference channel.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3366935&req=5

pone-0038392-g005: Phase differences along the chain of electrodes, including F4, FC4, C4, CP4, P4, and O2, at different times with step size of 6 ms.Red circles are the calculated phases for EEG signals with the average mastoid reference, black ones for EEG signals with an average reference; this result indicates that these phase differences do not sensitively depend on the reference channel.
Mentions: To calculate phases for the prominent alpha and theta oscillations, we adjusted the scale of the wavelet to make it centered at the peaks of these oscillations accordingly, which were determined individually on the basis of the above time-frequency analysis. After obtaining the phases of these oscillations, we then calculated phase differences for the electrodes along each of the three chains shown in Fig. 1. We found that there were significant time intervals during which there were progressive phase shifts along these chains. Figure 4 shows such a typical example for electrodes along the F4 to O2 chain with phase shifts in F-to-O direction, and Fig. 5 for phase shifts in O-to-F direction. The phase shift over the electrodes was then fitted to get a straight line.

Bottom Line: The spatiotemporal behavior of human EEG oscillations is investigated.Traveling waves in the alpha and theta ranges are found to be common in both prestimulus and poststimulus EEG activity.The dynamical properties of these waves, including their speeds, directions, and durations, are systematically characterized for the first time, and the results show that there are significant changes of prestimulus spontaneous waves in the presence of an external stimulus.

View Article: PubMed Central - PubMed

Affiliation: School of Physics, University of Sydney, Sydney, New South Wales, Australia.

ABSTRACT
The spatiotemporal behavior of human EEG oscillations is investigated. Traveling waves in the alpha and theta ranges are found to be common in both prestimulus and poststimulus EEG activity. The dynamical properties of these waves, including their speeds, directions, and durations, are systematically characterized for the first time, and the results show that there are significant changes of prestimulus spontaneous waves in the presence of an external stimulus. Furthermore, the functional relevance of these waves is examined by studying how they are correlated with reaction times on a single trial basis; prestimulus alpha waves traveling in the frontal-to-occipital direction are found to be most correlated to reaction speeds. These findings suggest that propagating waves of brain oscillations might be involved in mediating long-range interactions between widely distributed parts of human cortex.

Show MeSH