Johannes van den Berg
Affiliation: National Institute for Working Life
- Performance on a simple reaction time task while sleep deprivedJohannes van den Berg
Department of Work and the Physical Environment, National Institute of Working Life, Umea, Sweden
Percept Mot Skills 102:589-99. 2006..EEG and heart-rate variability measures did not correlate significantly with reaction time. Misses correlated significantly with subjective ratings and heart rate but only in the rested condition...
- Electroencephalography and subjective ratings of sleep deprivationJohannes van den Berg
Department of Work and the Physical Environment, National Institute for Working Life, Box 7654, 901 87 Umea, Sweden
Sleep Med 6:231-40. 2005..Ten volunteers participated in a laboratory study aimed to analyze the way changes in wakefulness were described in terms of EEG changes and subjective ratings...
- Heart rate variability during sedentary work and sleep in normal and sleep-deprived statesJohannes van den Berg
National Institute of Working Life, Umea, Sweden
Clin Physiol Funct Imaging 25:51-7. 2005..These HRV components were also significantly and negatively correlated with delta power densities. HRV does not seem to be a viable indicator of sleepiness; however, HRV may be useful for determining sleep stages...
- Sleepiness and head movementsJohannes van den Berg
Department of Work and the Physical Environment, National Institute for Working Life, Umea, Sweden
Ind Health 44:564-76. 2006..When rested, the changes in head movements correlated with ratings of sleepiness, EEG activity, and heart rate variability. Head movements can be a used as an indicator of sleepiness...
- Sound and vibration: effects on infants' heart rate and heart rate variability during neonatal transportBjörn Markus Karlsson
Department of Clinical Sciences, Umea University, Sweden
Acta Paediatr 101:148-54. 2012..To measure the effect of sound and whole-body vibration on infants' heart rate and heart rate variability during ground and air ambulance transport...