Influence of Ramadan on Neuroperformance in Healthy Workers

An Mertens, Schouteden Martijn, Lode Godderis


Background - During Ramadan, Muslims refrain from eating and drinking from dawn until sunset. In 2012, Ramadan took place during summer, with fasting periods up to 19 hours. Previous studies have reported delays in sleeping and waking time and consequently decreased daytime alertness. Nevertheless, data on the effects of Ramadan on neuroperformance are scarce.
Aims - We investigated the impact of Ramadan on tiredness and neuroperformance in Belgian Muslims.

Methods - 20 Subjects were tested outside of Ramadan, halfway the Ramadan and in the last week of the Ramadan. Tiredness was assessed with the Fatigue Assessment Scale (FAS) and alertness with the Stanford Sleepiness Scale (SSS). Neuroperformance was tested with the simple reaction time for reaction time (REA-t) and concentration (REA-sd), symbol digit substitution for visual perception (SDS), digit span backwards for short term memory (DSB) and hand-eye coordination test (EYE).

Results - Ramadan had no effect on FAS. SSS increased during Ramadan, but remained within normal physiological boundaries. There was no significant effect on REA-t and SDS. Ramadan had beneficiary effects on REA-sd, DSB and EYE.  There were no correlations between FAS or SSS and other neuroperformance parameters.
Conclusion - Daytime sleepiness moderately increases during Ramadan. Neuroperformance remains mostly unaffected. Concentration improved during Ramadan, but we observed are large interindividual differences.


ramadan; fasting; cognitive function; vigilance; sleepiness

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DOI: http://dx.doi.org/10.18103/mra.v0i3.194


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