Sleep inertia associated with a 10-min nap before the commute home following a night shift: A laboratory simulation study

Night shift workers are at risk of road accidents due to sleepiness on the commute home. A brief nap at the end of the night shift, before the commute, may serve as a sleepiness countermeasure. However, there is potential for sleep inertia, i.e. transient impairment immediately after awakening from the nap. The authors investigated whether sleep inertia diminishes the effectiveness of napping as a sleepiness countermeasure before a simulated commute after a simulated night shift. N = 21 healthy subjects (aged 21–35 y; 12 females) participated in a 3-day laboratory study. After a baseline night, subjects were kept awake for 27 h for a simulated night shift. They were randomised to either receive a 10-min nap ending at 04:00 plus a 10-min pre-drive nap ending at 07:10 (10-NAP) or total sleep deprivation (NO-NAP). A 40-min York highway driving task was performed at 07:15 to simulate the commute. A 3-min psychomotor vigilance test (PVT-B) and the Samn-Perelli Fatigue Scale (SP-Fatigue) were administered at 06:30 (pre-nap), 07:12 (post-nap), and 07:55 (post-drive). In the 10-NAP condition, total pre-drive nap sleep time was 9.1 ± 1.2 min (mean ± SD), with 1.3 ± 1.9 min spent in slow wave sleep, as determined polysomnographically. There was no difference between conditions in PVT-B performance at 06:30 (before the nap). In the 10-NAP condition, PVT-B performance was worse after the nap (07:12) compared to before the nap (06:30); no change across time was found in the NO-NAP condition. There was no significant difference between conditions in PVT-B performance after the drive. SP-Fatigue and driving performance did not differ significantly between conditions. In conclusion, the pre-drive nap showed objective, but not subjective, evidence of sleep inertia immediately after awakening. The 10-min nap did not affect driving performance during the simulated commute home, and was not effective as a sleepiness countermeasure.

• Record URL:
  https://doi.org/10.1016/j.aap.2015.11.010
• Record URL:
  http://www.sciencedirect.com/science/article/pii/S0001457515301263
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00014575
• Supplemental Notes:
  • Abstract reprinted with permission of Elsevier.
• Authors:
  • Hilditch, Cassie J
  • Dorrian, Jillian
  • Centofanti, Stephanie A
  • Van Dongen, Hans P
  • Banks, Siobhan
• Publication Date: 2017-2

Language

• English

Media Info

• Media Type: Web
• Features: Figures; References;
• Pagination: pp 411-415
• Serial:
  • Accident Analysis & Prevention
  • Volume: 99, Part B
  • Issue Number: 0
  • Publisher: Elsevier
  • ISSN: 0001-4575
  • Serial URL: http://www.sciencedirect.com/science/journal/00014575

Subject/Index Terms

• TRT Terms: Alertness; Commuting; Countermeasures; Fatigue (Physiological condition); Night shifts; Sleep
• Subject Areas: Highways; Safety and Human Factors;

Filing Info

• Accession Number: 01627549
• Record Type: Publication
• Files: TRIS
• Created Date: Feb 27 2017 5:12PM