What about regular people nowadays?
No different. The spark might come from a NatGeo special on the universe. According to NASA, more is unknown than is known. We know how much dark energy there is because we know how it affects the Universe's expansion. Other than that, it is a complete mystery. But it is an important mystery. It turns out that roughly 68% of the Universe is dark energy. Dark matter makes up about 27%. The rest - everything on Earth, everything ever observed with all of our instruments, all normal matter - adds up to less than 5% of the Universe. When it comes to the oceans, we know only 3%.
It might occur when a child is born. The Holy Spirit sparks enlightenment by moving hearts. St. Bakhita's spark was ignited when she looked at the crucified Christ on a crucifix. She recognized by his wounds that this "paron" understood what she had endured in her life.