Experiment: IO neurons exhibit sharp activity peaks at twitch onset Folder: IO Subjects: 7- to 9-day-old infant rats (N=20). Neural activity acquired at 12.5 or 25 kHz, amplified 10,000 times, and bandpass filtered between 500-5000 Hz. A threshold for spike templates was set to at least 2 times the noise band. Spike sorting was done in Spike2 using template matching. Templates were then assessed using principal components analysis and waveforms exceeding 3.5 standard deviations from the mean of the template were excluded from subsequent analysis. Electromyography (EMG) data acquired at 1 kHz, amplified 10,000 times, and bandpass filtered between 300-5000 Hz. To establish an EMG threshold for determining behavioral state, EMG signals were first rectified and then smoothed (smoothing time constant = 1 ms). 5, 1-s segments of periods of atonia and muscle tone were used to calculate mean rectified EMG for each state (segments were randomly selected throughout each run). The midpoint of the average for atonia and the average wake was the threshold for state change between sleep and wake (>/= 1-s duration required for change to be recorded). Wake onset was determined using the threshold for state change between sleep and wake described above for those EMGs showing a significant correlation with twitches (see below). An event marker for wake onset was manually added to the record for wake movements that 1) exceeded the threshold, 2) did not show movement artifact in the neural record, and 3) was not within 1 s of another wake onset. Twitch identification was accomplished using a threshold >/=3 times the average value of atonia. The threshold was variable depending upon the level of noise in the EMG. Twitches were made into events using Spike2, when the EMG crossed the threshold the event was marked, unless it occurred within 300 ms ofthe preceding twitch event in which case it was not counted. Files were exported from Spike2 to .mat files. Each Matlab file represents one run for one subject, if more than one run occurred for a subject the run number is identified after the subject ID. In each folder there are subfolders with the entire run ("XX raw sorted") and another folder containing only active sleep for each run ("XX AS"). Below is a description of the objects in the .mat files *RAW SORTED FILES* Ranges: Start and stop of periods that are not active sleep *4 of the 6 EMGs below were used* ipsi nuchal: Raw ipsilateral nuchal EMG ipsi fl: Raw ipsilateral forelimb EMG contra nuchal: Raw contralateral nuchal EMG contra fl: Raw contralateral forelimb EMG contra hl: Raw contralateral hindlimb EMG ipsi hl: Raw ipsilateral hindlimb EMG UnitX: waveform from MUA channel (Channels 1-16) W-onset; event channel for wake onsets scoring: Observer scored twitches and wake movements Ranges.times: start and stop times for range Ranges.codes: binary representation of range. 1=On; 0=Off Ranges.text: "On" "Off" For EMG and Waveform objects .values: value of the sample .times: time of the sample scoring.times: time of key press scoring.codes: first column, code of key press. 49=twitch; 50=wake movement For wake onset event objects .times: time of wake onset *AS FILES* edits: denotes removal of range *4 of the 6 EMGs below were used* ipsi nuchal: Raw ipsilateral nuchal EMG ipsi fl: Raw ipsilateral forelimb EMG contra nuchal: Raw contralateral nuchal EMG contra fl: Raw contralateral forelimb EMG contra hl: Raw contralateral hindlimb EMG *4 of the 6 EMGs below were used* ipsi ntw: ipsilateral nuchal twitch event ipsi ftw: ipsilateral forelimb twitch event ipsi htw: ipsilateral hindlimb twitch event contra ntw: contralateral nuchal twitch event contra ftw: contralateral forelimb twitch event contra htw: contralateral hindlimb twitch event UnitX: waveform from MUA channel (Channels 1-16) scoring: Observer scored twitches and wake movements edits.times: time from zero of removed range edits.text: gives text value of the duration of the range remove. "Cut: XXs" For EMG and Waveform objects .values: value of the sample .times: time of the sample For twitch event objects .times: time of twitch scoring.times: time of key press scoring.codes: first column code of key press. 49 - twitch; 50 - wake movement *Notes* Files with fewer than 4 EMG channels had one or two bad EMGs 7-zip used to compress files