Cortical and spinal evoked potential response to electrical stimulation in human rectum

Table 1 Summary amplitude data for graded electrical stimulation (mean ± SD)

N1/P1 (μV)	Spinal	Cortical
Threshold	21 ± 4	12 ± 3
2.0 × threshold	49 ± 6	26 ± 5

Table 2 Summary data for latencies and amplitudes for spinal and cortical evoked potentials (mean ± SD)

	Spinal	Cortical
N1 latencies (ms)	4.6 ± 0.4	136.1 ± 4.2
P1 latencies (ms)	6.8 ± 0.5	233.6 ± 12.8
N1/P1 amplitude (μV) (1.5 × threshold)	38 ± 7	19 ± 3

Table 3 Summary data for reproducibility of latencies and amplitudes for spinal and cortical evoked potentials with repeat testing (mean ± SD)

	Spinal	Cortical
N1 latencies (ms)	4.4 ± 0.5	132.1 ± 6.1
P1 latencies (ms)	6.6 ± 0.6	229.8 ± 15.8
N1/P1 amplitude (μV)	35 ± 8.5	18.6 ± 3.4