Table 1 EEG description for EEG-vigilance stage and operational definition of arousal stability score and assessment criteria

0

Low amplitude, desynchronized non-alpha EEG without horizontal SEM

Unique occurrence of 0 and A1

More than 2/3 of all segments are attributed as 0/A1 or 0/A stages

Unique occurrence of 0 and A

A1

Occipital dominant alpha

Stage B1 in third 5 min

At least 1/3 of all segments are attributed as stage B1

A2

Shift of alpha to central and frontal areas

Stage B1 in second 5 min

A3

Continued frontalization of alpha

Stage B1 in first 5 min

B1

Low amplitude, desynchronized EEG with horizontal SEM

Stage B2/3 in third 5 min

At least 1/3 of all segments are attributed as stage B2/3

Stage B2/3 in second 5 min

B2/3

Dominant delta and theta

Stage B2/3 in first 5 min

C

Occurrence of K-complex and sleep spindles

Stage C in third 5 min

Occurrence of stage C

Stage C in second 5 min

Stage C in first 5 min