Abstract: An electroencephalogram signal processing apparatus includes an interface and one or more processors. The interface receives, from each of a plurality of electrodes attached to a head of a subject, an electroencephalogram signal corresponding to a change over time in a brain activity potential of the subject. The processor obtains a value of an electroencephalogram parameter for each of the plurality of electrodes by processing the electroencephalogram signal, and the processor outputs data for plotting the value on a radar chart. A plurality of regions to each of which at least one electrode is attached are set in the head. Each of a plurality of coordinate axes provided in the radar chart is associated with a corresponding one of the plurality of regions.

Abstract: A fluroinated graphite having the formula (C.sub.x F).sub.n wherein x is a numerical value of about 2.0 to about 5.5 and n refers to an indefinite number of the recurring (C.sub.x F) unit and having a crystalline structure exhibiting a peak at about 13.7.degree. to about 15.0.degree. in terms of an angle of 2.theta. corresponding to the diffraction at the (001) plane in the X-ray diffraction pattern, a peak in the vicinity of 685.3 eV due to the F.sub.ls and two peaks in the vicinity of 287.5 eV and 284.3 eV due to the C.sub.ls in the spectrum of electron spectroscopy of chemical analysis, two peaks in the vicinity of 1100 cm.sup.-1 and 1240 cm.sup.-1 in the IR spectrum, and an electric conductivity of at least about 10.sup.-8 .OMEGA..sup.-1 cm.sup.-1, and being thermlly stable in air up to 200.degree. C.