The human electroencephalogram (EEG) may be the most complex set of signals in nature and is certainly the most complicated phenomenon routinely subjected to scientific experimentation. That electrical potentials are detectable at the scalp at all is the result of some fortuitous neural architecture. Human neocortex consists of tightly packed arrays of columns, six neurons deep, aligned perpendicular to the pia matter directly below the skull (Mountcastle, 1978).
Neurofeedback for epilepsy
With electroencephalographic (EEG) biofeedback (or neurofeedback), it is possible to train the brain to de-emphasize rhythms that lead to generation and propagation of seizure and emphasize rhythms that make seizures less likely to occur. With recent improvements in quantitative EEG (qEEG) measurement and improved neurofeedback protocols, it has become possible in clinical practice to eliminate seizures or reduce the amount of medication required to control them.
EEG Examples
The highest frequency which can be accurately represented is one-half of the sampling rate.The sampling rate here is below the Nyquist frequency, so the result of sampling is nothing like the input.