Zhang & Wamsley 2019

Dream EEG and Mentation (DREAM) data set

---Data set information---

Common name: Zhang & Wamsley 2019

Full name: N/A

Authors: Jing Zhang, Erin Wamsley

Location: Furman University, Greenville SC

Year: N/A

Set ID: [SET BY DATABASE]

Amendment: [SET BY DATABASE]

Corresponding author ID: [SET BY DATABASE]

Download URL: [SET BY DATABASE]

Previous publications:

Zhang, J., & Wamsley, E. J. (2019). EEG predictors of dreaming outside of REM sleep. Psychophysiology, 56(7), e13368.

Correspondence:

Dr. Erin Wamsley: erin.wamsely@furman.edu

---Metadata---

Key ID: [SET BY DATABASE]

Date entered: [SET BY DATABASE]

Number of samples: [INFERRED BY DATABASE]

Number of subjects: [INFERRED BY DATABASE]

Proportion REM: [INFERRED BY DATABASE]

Proportion N1: [INFERRED BY DATABASE]

Proportion N2: [INFERRED BY DATABASE]

Proportion experience: [INFERRED BY DATABASE]

Proportion no-experience: [INFERRED BY DATABASE]

Proportion healthy: [INFERRED BY DATABASE]

Provoked awakening: Yes

Time of awakening: Mixed

Form of response: Free

Date approved: [SET BY DATABASE]

---How to decode data files---

Sleep stage codes in the filenames/Case IDs:

"SO#" = sleep onset reports collected after <=90sec of sleep."#" represents the order in which reports were collected.

NREM = reports intended to be collected following at least 10min of PSG-defined N2

REM = reports intended to be collected following at least 5min of PSG-defined REM sleep

Morning = a final report collected on morning awakening, regardless of sleep stage

The INTENDED sleep stage indicated by these labels does not necessarily match the ACTUAL sleep stage of the last epoch just before the dream report marker, as listed in records.csv. This is for two reasons:

1 - Sometimes, research assistants inadvertantly elicited reports from the wrong sleep stage

2 - In other cases, the dream report marker was delayed for a few seconds, and a few seconds of wake preceeds the dream report marker, even though the participant had mostly been asleep prior to the marker.

In our publication referenced here, we excluded reports that were concluded to be from the incorrect pre-awakening stage.

In this archive, we include those reports.

In some cases, participants were actually scored as being AWAKE just before a report was elicited.

In records.csv, 0 = last epoch before the report was WAKE.

--Treatment group codes--

N/A

---Experimental description---

See:

Zhang, J., & Wamsley, E. J. (2019). EEG predictors of dreaming outside of REM sleep. Psychophysiology, 56(7), e13368.

--DREAM categorization procedure--

In this study, we define a “dream” as any mental experience recalled from sleep. Reports were coded for the presence of dream content by 2 independent judges, who were blind to sleep stage. For each report, judges assessed whether the report contained a description of any mental content.

Participants were not asked to assess whether they might have been dreaming, but failed to recall the dream. Therefore, the dream reports are coded only as:

0 = no experience

2 = experience

---Technical details---

N/A

--Data acquisition--

High-density electrode caps (BrainProducts) were used to record EEG throughout the night (58 EEG electrodes placed following the international 10-10 system). During recording, EEG signals were referenced to the contralateral mastoid to aid on-line sleep staging. Additionally, muscle tone was monitored using electromyography (EMG; bipolar chin leads) and eye movement was monitored using electrooculography (EOG; left and right outer canthus). All data were recorded at 400Hz using a Grass-Telefactor AURA amplifier with a high-pass filter at 0.1Hz.

--Data preprocessing--

These data have been filtered a 0.3-35Hz, and a 60Hz notch filter is applied.

Eye channels are referenced to the contralateral mastoid.

The two chin leads are referenced to eachother.

EEG channels are currently unreferenced -- prior to analysis, an appropriate EEG reference needs to be selected.

A1 = left mastiod

A2 = right mastiod

EEG electrodes labeled according to the 10-10 system.

Ground electrode was placed on the forehead.