The Catastrophic State is the point where a Therian is pushed into anger and the need to either calm or survive kicks in.  At this state a Therian still has the opportunity to gear down and go back to normal.  However, on the flip side this is a state where the flight/fight response is starting to kick in and sending signals to the body to prepare.  Mentally a Therian at this point is losing more of themselves to their instincts.