Cats had their neocortices removed but still displayed characteristics of extreme anger resulting from mild stimuli.
After the surgery, Bard observed that the animals would have an extreme rage reaction to stimuli that had previously produced little to no response, like touching the tail.
[11] A study by Reis and Gunne (1965) found that electrically stimulating the amygdala of cats caused sham rage, which resulted in a decrease in the presence of adrenaline and noradrenaline.
They believed this was because the excited defense reaction known as sham rage caused such a huge increase in the release of the neurotransmitters that the brain could not resynthesize noradrenaline fast enough to keep up.
[14] This is not surprising, as the role of the hypothalamus in generating the internal experience of rage has been mapped in rats, cats, and humans.
[15] Three known causes of hypothalamic discharge are depolarization of the hypothalamus via electrode stimulation,[16][17] carbon monoxide poisoning and insulin hypoglycemia.
While experiencing sham rage, the human body will show both internal and external signs of physical distress.