A possible answer could be parasympathetic.
The parasympathetic nervous system is the nervous system is characterised by things such as mentioned above "slower respiration and heart rate" because it is the system that responds to stimulation, which can occur during eating, digestion, defecation, etc.
It is also reponsible for well known reaction such as "flight-or-fight" and other similar ones.
Hope it helped,
BioTeacher101