A non-invasive method to detect an intentional brain signal from a subject comprising: (a) attaching at least a single sensor to the subject; (b) obtaining brain signal data indicative of brain activity using the at least one single sensor; (c) analyzing the brain signal data indicative of brain activity, wherein analyzing comprises computing a spectrogram of the brain signal data, normalizing the spectrogram of the data at least once, time over frequency, and normalizing the spectrogram of the data at least once, frequency over time to produce a doubly normalized spectrogram, and wherein analyzing of the brain signal data further includes: determining, from the doubly normalized spectrogram, a summed first power corresponding to a gamma frequency band; determining, from the doubly normalized spectrogram, a summed second power corresponding to an alpha frequency band; and determining a summed alpha-to-gamma ratio based on the first summed power corresponding to the gamma frequency band and the second summed power corresponding to the alpha frequency band; (d) correlating the summed alpha-to-gamma ratio of said analyzed data to an intentional higher cognitive function from the subject; and (e) after the correlating step, translating the summed alpha-to-gamma ratio of the analyzed data to effect a task associated with the intentional higher cognitive function, wherein the task includes a movement of an artificial prosthesis. (a) attaching at least a single sensor to the subject; (b) obtaining brain signal data indicative of brain activity using the at least one single sensor; (c) analyzing the brain signal data indicative of brain activity, wherein analyzing comprises computing a spectrogram of the brain signal data, normalizing the spectrogram of the data at least once, time over frequency, and normalizing the spectrogram of the data at least once, frequency over time to produce a doubly normalized spectrogram, and wherein analyzing of the brain signal data further includes: determining, from the doubly normalized spectrogram, a summed first power corresponding to a gamma frequency band; determining, from the doubly normalized spectrogram, a summed second power corresponding to an alpha frequency band; and determining a summed alpha-to-gamma ratio based on the first summed power corresponding to the gamma frequency band and the second summed power corresponding to the alpha frequency band; determining, from the doubly normalized spectrogram, a summed first power corresponding to a gamma frequency band; determining, from the doubly normalized spectrogram, a summed second power corresponding to an alpha frequency band; and determining a summed alpha-to-gamma ratio based on the first summed power corresponding to the gamma frequency band and the second summed power corresponding to the alpha frequency band; (d) correlating the summed alpha-to-gamma ratio of said analyzed data to an intentional higher cognitive function from the subject; and (e) after the correlating step, translating the summed alpha-to-gamma ratio of the analyzed data to effect a task associated with the intentional higher cognitive function, wherein the task includes a movement of an artificial prosthesis. <EOS>