Vol 69, No 2 (2018)
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Published online: 2018-06-22

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Analysing the effects of working period on psychophysiological states of seafarers

Barış Özsever1, Leyla Tavacıoğlu2
Pubmed: 29939384
IMH 2018;69(2):84-93.


Background: Human factor has become a critical issue due to the fact that all operational processes in
maritime transportation have been accelerated with technological innovations. Irregular and long working
hours, rapid change of working environments and other organisational and/or individual factors have negative
impact on the performance of the seafarers as well as other transportation workers and/or shift workers.
Seafarers working under the influence of these stressor factors, naturally, are affected from psychophysiological
and cognitive aspects, which in return decrease their overall performances. The study mainly aimed to
investigate which of the above mentioned affecting factors had greater impact on seafarers’ performances.

Materials and methods: For this purpose, data for 14 healthy male seafarers on board different vessels was
collected. The collected data included the number of port visits, frequency of change of circadian rhythm, total
working hours and watchkeeping periods in the recent month. In order to analyse the psychophysiological
effect of working period, electrodermal activity and heart rate variability measurements for arousal mood
and data from 2-choice reaction time tests for cognitive performance were collected from the seafarers.
Results: Obtained data was analysed in SPSS software programme applying multiple regression with factor
analysis to model the dependence between psychophysiological states of seafarers and working periods.

Conclusions: According to the results, it was determined that the change of circadian rhythm is the main
determinant factor for seafarers. The results showed that when seafarer’s circadian rhythm is changed
more frequently, they experience more drowsiness.

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