抄録
Magnetwncephalography (MEG) is a useful method for diagnosis of functional brain disease as well as for the study of higher brain functions, such as cognition, memory, and blending of brain functions. We studied frontal midline theta (Fmθ) activity in human subjects during mental processes such as arithmetic calculation. It is said that Fmθ activity is best observed when human subjects can concentrate their attention on a task that is not d L continued. Fmθ id a 6∼7 Hz rhythmic wave with a duration of a few seconds. Fmθ activity is observed in the front central area of the head. Electroencephalograms (EEGs) and MEGs of Fmθ were measured simultaneously during mental calculation. We analyzed these waveforms on the basis of both topographic EEG maps and magnetic field measurements, and estimated some patterns of source models of Fmθ from EEG topography and MEG. We also simulated Fmθ by using these models and spatial patterns of EEG and MEG.