Table 2 List of covariates collected for each of the sessions

General

 Date

scanDate

Expressed in format ‘dd. mm. yyyy’

 Time

scanTime

Time of start of scanning session

 Minimum outside temperature for the day of the scan (°C)

minTemp_C

All weather variables were collected from the German Weather Service [27]

 Maximum outside for the day of the scan temperature (°C)

maxTemp_C

 Wind (km/h)

wind_km_h

 Precipitation (mm)

precip_mm

 Kind of precipitation

precip_form

Precipitation codes are as follows:

0: No precipitation

1: Only scattered precipitation

2: Only scattered precipitation in liquid form

3: Only scattered precipitation in frozen form

6: Rain or drizzle

7: Precipitation in frozen form

8: Precipitation in liquid and frozen form

9: Measurement error

 Atmospheric pressure (hp)

atmPressume

 Relative humidity (%) (daily average)

relHumidity

 Hours of sunshine

sunshine_hrs

Scanner characteristics

 MR room temperature (°C)

MR_Room_Temperature

 MR room humidity (%)

MR_Room_Humidity

 MR helium level (%)

MR_HeliumLevel

Behaviour during scan

 Slept during scan

sleptDuringScan

Binary variable (0/1)

 Rumination

ruminationDuringScan

1–6 Likert scale

 Anxiety

anxietyDuringScan

1–6 Likert scale

 Physiological variables

 Day of menstrual cycle

menstrualCycleDay

Since first day of last period. Additional information is available on request

 Caffeine intake in the last 24 h

caffein_last24hs_cups

In number of cups of coffee

 Caffeine intake in the last 2 h

caffein_last2hs_cups

In equivalent number of cups of coffee

 Chocolate intake (g) in the last 24 h

chocolate_last24hs_gramms

 Cacao intake (%) in the last 24 h

chocolate_last2hs_gramms

 Chocolate intake (g) in the last 2 h

cacao_last24hs_percentage

 Cacao intake (%) in the last 2 h

cacao_last2hs_percentage

 Alcohol intake in the last 24 h

alcohol_last24hs_drinks

In number of alcoholic drinks

 Cigarettes smoked in the last 24 h

cigarettes_last24hs

 Marihuana consumed in the last 24 h (in number of cigarettes)

marihuanaCigarettes_last24hs

 Liquid intake in the last 24 h

liquid_last24hs_liters

 Sweets intake in the last 24 h

sweets_last24hs

1–6 Likert scale

 Salt intake in the last 24 h

salt_last24hs

1–6 Likert scale

 Weight (kg)

weight_kg

Weight was measured without shoes but otherwise with clothes on

 Blood pressure (mmHg, systolic and diastolic)

bloodPressure_systolic_mmHg, bloodPressure_diastolic_mmHg

 Saliva estrogen

 Saliva testosterone

 Physical pain

physicalPainDuringScan

Experienced during scan, 1–6 Likert scale

 General health rating

generalHealth_last24hs

Subjective rating of the last 24 h, 1–6 Likert scale

 General stress rating

generalStress_last24hs

Subjective rating of the last 24 h, 1–6 Likert scale

Behavioural and affective variables

 Ease of concentration

easeOfConcentration_last24hs

In the last 24 h, 1–6 Likert scale

 Hours of work in the last 24 h

hoursOfWork_last24hs

 Hours of free time in the last 24 h

hoursFree_last24hs

 Hours of sport in the last 24 h

hoursSport_last24hs

 Hours spent outdoors in the last 24 h

hoursSpentOutdoors_last24hs

 Hours spent directly interacting with electronic devices in the last 24 h

hoursUsingScreens_last24hs

 Hours spent in active social interaction in the last 24 h

hoursActiveSocialInteraction_last24hs

 Hours spent in passive social interaction in the last 24 h

hoursPassiveSocialInteraction_last24hs

 Positive and negative affect (PANAS scales)

PANAS_[itemName]

During the scanning. Individual questions are listed in the covariates data file

 Sleep quality

sleepQuality_lastNight

1–6 Likert scale, with its extremes specified as 1: “Very badly” to 6: “Very well”

 Can remember dreams from previous night

rememberDreams_fromLastNight

Binary variable (0/1)

 Frequency of day dreams (mindwandering) in the last 24 h

dayDreams_last24hs

1–6 Likert scale

 Time went to bed the previous night

time_bed

Measured with a FitBit activity tracker and completed manually in case of omission

 Time spent in bed the previous night

time_slept_min

Measured with a FitBit activity tracker and completed manually in case of omission

 Number of steps made in the last 24 h

number_steps

Measured with a FitBit activity tracker

 Distance walked in the last 24 h

walk_distance

Measured with a FitBit activity tracker

 Number of stories climbed in the last 24 h

number_stories

Measured with a FitBit activity tracker

 Calories burned in the last 24 h

calories_burned

Measured with a FitBit activity tracker