How does stress affect the amygdala, and what is the connection between the amygdala and stress?
When we experience stress, a process is triggered in the brain, starting in the hypothalamus, in both humans and (other) mammals. As soon as the hypothalamus is stimulated, it produces a hormone that acts on the pituitary gland (corticotropin-releasing hormone, or CRH). The pituitary gland (in humans, a small gland with a diameter of about 1 centimeter and a weight of up to 1 gram) is located just below the hypothalamus. This gland then produces adrenocorticotropic hormone (ACTH), which enters the kidneys via the bloodstream. ACTH stimulates the adrenal glands to produce the stress hormone cortisol. In addition to cortisol, there are two other stress hormones: adrenaline and noradrenaline.
THE AMYGDALA IS THE EMOTIONAL CONTROL CENTER IN THE BRAIN
The right amygdala performs more specialized functions than the left amygdala.
General veterinary neuroanatomy describes the most important functions of the right amygdala as follows:
1. Rapid analysis and response to perceptions: The left amygdala is more closely associated with “detailed analysis and learned fear.” The right amygdala, on the other hand, provides a rapid, instinctive response based on dynamic environmental stimuli.
2. Detecting immediate danger: The right side is much more involved than the left side in the automatic processing of external stimuli that may indicate a threat. This is why cattle and pigs in particular often react with a rapid startle response, which often manifests itself in flight behavior. This is completely normal; they associate something unknown with “danger or a predator,” which is a natural survival strategy.
3. Emotional, negative arousal: When cattle or pigs are under stress, their right amygdala usually shows higher activity than their left amygdala. The right amygdala is therefore associated with uncertainty, fear, and aggression.
4. Visual recognition: Research shows a pattern suggesting that the right amygdala plays a specific role in recognizing both species and threats, followed by a response to this recognition.
How the brains of humans and animals work will require years of in-depth scientific research.
For my part, I apply the available knowledge in my daily interactions with animals (and people).
That way, everyone knows exactly whether to turn left, right, or even go straight ahead.
Source photos Ronald Rongen