The Biological Layer (Bio)
Every reaction your dog shows is, in fact, the result of a signal from the nervous system and the hormones circulating in the blood. Many different biological factors, such as genetic heritage, hormonal balance (cortisol, adrenaline, etc.), unnoticed physical pain or diet, form the underlying basis of behavior. If this biological system is constantly producing a sense of threat, the dog enters survival mode against their will, the learning mechanism in their brain switches off, and they cannot behave rationally.

