How does sleep stage affect the results of somatosensory evoked potentials (SEPs) testing?

Updated: Oct 25, 2019
  • Author: Andrew B Evans, MD; Chief Editor: Selim R Benbadis, MD  more...
  • Print


Noguchi et al, in a study that evaluated the changes of frontal and parietal SEP in the awake state and compared them with SEPs in different stages of sleep in 10 healthy adult subjects, found that frontal and parietal SEP components were affected differently as sleep stages progressed. [42] The amplitudes of frontal components were increased in sleep, whereas the amplitudes of parietal components were decreased.

The most discordant changes occurred in stages III/IV. The amplitudes for the frontal N18-P22-N30 complex and the parietal N20-P26-N32 complex increased from stage II to stages III/IV, whereas those for frontal N30-P40 and parietal N32-P40 decreased. [42] P14 and frontal N18 latencies did not change significantly. The further latencies showed progressive prolongation from the awake state to slow-wave sleep.

The SEP waveforms and latencies in rapid eye movement (REM) sleep were similar to those in the awake state. [42] Amplitudes for frontal peaks remained slightly higher and amplitudes for parietal peaks slightly lower. Apparently both excitatory and inhibitory influences may mediate these sleep stage–related changes.

Note that significant neuropathy may be a complicating factor in acquiring SEP, and the development of cortical potentials may be irregular, delayed, dispersed, and of poor amplitude. Generally, some of these difficulties can be overcome by increasing the number of samples collected.

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!