According to Bernhard Hommel, a psychologist at Leiden University in the Netherlands who led the new study, culture has long been known to distort visual perception.
In a bid to see if religious differences skew perception, Hommel's team tested 40 Dutch atheist and Calvinist university students, who, religion aside, had similar cultural backgrounds.
In the study, Hommel's team showed participants a large triangle or square made of either smaller triangles or squares on a computer screen.
The volunteers had to focus on either the big object or its component shapes, and indicate whether they were square or triangular.
Both groups recognised the large shapes more quickly than small, embedded ones, but the Calvinists picked out the smaller shapes 30 milliseconds faster than atheists, on average - a small, but significant, difference, reports New Scientist.
According to the lead expert, this could reflect a greater focus on self than external distractions for Calvinists.
He suggests it may even be a cognitive consequence of their religion and speculates that Calvinists might be more inward looking than atheists because they have lived their whole lives with an emphasis on minding their own business.
The study has been published in the journal PLoS ONE.