Import sleep data files into Neuroscore V3.0 software and visually inspect data.
Exclude data with interruptions, noise, or issues related to battery status from further analyses.
Use the DSI-provided "sleep scoring 2" script for analysis, incorporating EEG, EMG, and activity channels for scoring (Tools – Rodent scoring 2 visual Tuning).
Specific power levels are considered indicative of different sleep stages:
Delta power levels with a delta ratio of 0.5 are associated with a maximum probability of REM/Wake, and a NREM delta ratio of 1 represent a maximum probability of NREM.
Theta power levels with a theta to delta ratio of 1.3 indicate a maximum probability of Wake/NREM, and a theta to delta ratio of 3 indicate a maximum probability of REM.
EMG power levels with an EMG ratio of 1.1 are considered representative of a maximum probability of REM to NREM, and an EMG ratio of 2.4 indicate a maximum probability of Wake.
An activity count of 0.1 is defined for the active wake phase. To avoid separating different wake stages, the scoring rules combine active wake and wake based on the activity channel.
Artifact detection thresholds are set on a per-recording basis, with most recordings having thresholds set to 0.5mV for both EEG and EMG.
Stage transition probabilities based on EEG, EMG, and activity are defined as follows:
Wake to NREM: 90%
Wake to REM: 90%
NREM to Wake: 80%
NREM to REM: 90%
REM to Wake: 70%
REM to NREM: 80%
The contributing factors of Delta, Theta/Delta, and EMG are considered equally important for all recordings. Sleep scoring is then obtained within 20s windows, and any recording with more than 1% artifacts is excluded from further analyses.