A method for characterizing the physiological state of a patient from an analysis of its cerebral electrical activity, making application and monitoring device

The invention relates to a method for detecting a physiological condition of a patient physiological condition deviating from a reference, wherein, after determining in each of frequency bands Q R reference matrices with PR q [1 ... Q] and r [1 ... R] corresponding to the physiological state of reference, the following steps are repeated in a loop: performing in M ​​time segments measures an electroencephalographic signal; filter and focus the measurements in Q frequency bands to obtain and determine MXQ normalized spatial covariance matrices; for each time segment m, calculating a difference in the physiological state of reference, and comparing each of the differences in the reference physiological state than a determined threshold. The invention also relates to making implementation monitoring device.