Meshberger also argues that there appears to be communication present despite the gap between the depicted Adam and God, just as neurons transmit biochemical information across synaptic clefts. Further, below the right arm of God, the painting shows a sad angel in an area of the brain that is sometimes activated on PET scans when someone experiences a sad thought. God is superimposed over the limbic system, the emotional center of the brain and possibly the anatomical counterpart of the human soul. God's right arm extends to the prefrontal cortex, the most creative and most uniquely human region of the brain.

there's no way Michalangelo knew that though

Alternatively, it has been observed that the red cloth around God has the shape of a human uterus (one art historian has called it a "uterine mantle"[6]), and that the scarf hanging out, coloured green, could be a newly cut umbilical cord.

if this isn't it, occam's razor would at least say that this is a better explanation than 'brain'