Thanks Josh.

To my limited knowledge, the PAG is indeed crucial for the expression of many of the behaviours we associate with fear, including jumping with fright (startle reflex), fleeing, and loss of bladder control…

The actual sensation of “fear” is a bit of a mystery — after all, we don’t know if the animals we study actually have a “fear” sensation

For more on the PAG’s role in fleeing, I wrote up some of Tiago Branco’s cool work on this here: “When To Flee” https://link.medium.com/tGpnrTv2W5