Table 2.

Data provided by the encephalograph following spectral analysis (for an EEG segment of 20 sec).

		Median value for EEG rhythms							Indices for the whole spectrum
		Delta	Theta	Alpha 1	Alpha 2	Beta 1	Beta 2	Total	Edge	Av	Median	Peak
P3	A1	2.766	2.8	4.785	3.615	2.088	1.515	17.568	19.141	10.16	9.57	10.16
P4	A2	3.727	3.78	6.639	3.854	1.521	0.783	20.304	13.672	8.789	9.18	10.16
O1	A1	2.257	2.971	13.644	16.39	2.591	1.895	39.745	14.453	10.35	9.961	10.16
O2	A2	2.416	4.028	13.17	13.79	1.93	1.398	36.729	11.914	9.961	9.961	10.16

Edge (edge frequency): the frequency that establishes, at a value initially set by the operator (90% in our case), the ratio—the left area/the whole area of the spectrum; Av (average frequency): the frequency corresponding to the center of gravity of the spectrum area; median (median frequency): the frequency that divides the area into two equal parts; peak (peak frequency): the maximum energy frequency.