Brains II

That brain growth is up and out then down and under very similar to ram’s horns. The space of the groove travels with this arcing swelling growth as the two sides fuse. The original central space is the third ventricle. The dragged ram horn hollow centers become the left and right ventricles.

Nerve pathways that were forming get dragged along this path as the lead end wraps around wide of the original growing region to become the temporal lobe. There are differing chemistry types to different system functions that optimise and segregate those functions. So the chemistry also follows the ram horn brain & ventricle formation (BELOW: left upper white path is cholinergic – for example).