Magnetoencephalographic (MEG) Characterization of Dynamic Brain Activation Basic Principles and Methods of Data Collection and Source Analysis
نویسندگان
چکیده
Timing is essential for proper brain functioning. Magnetoencephalography (MEG) and electroencephalography (EEG) are at present the only noninvasive human brain imaging tools that provide submillisecond temporal accuracy and thus help to unravel dynamics of cortical function. The advantage of MEG over EEG is that skull and scalp, which affect the electric potential distributions, do not smear the magnetic signals and MEG is thus able to see cortical events 'directly through the skull'. MEG (and EEG) reflect the electrical currents in neurons directly, rather than the associated hemodynamic or metabolic effects.
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