Its worth remembering that the Brain operates on one big, long, Cycle. And I assure you, the Hypothalamus plays a very, very big part in that Process. More so than just being a stimulant.
"The
hypothalamus and
periaqueductal gray of the midbrain are the most critical areas controlling aggression in mammals, as shown in studies on cats, rats, and monkeys. These brain areas control the expression of all the behavioral and autonomic components of aggression in these species, including vocalization. They have direct connections with both the brainstem nuclei controlling these functions and areas such as the amygdala and prefrontal cortex.Electrical stimulation of the hypothalamus causes aggressive behavior[SUP]
[34][/SUP] the hypothalamus expresses receptors that help determine aggression levels based on their interactions with the neurotransmitters serotonin and vasopressin.[SUP]
[35]"
"[/SUP]The neurotransmitter
vasopressin causes an increase in aggressive behavior when present in large amounts in the anterior hypothalamus (Delville et al. 1997). The effects of
norepinephrine, cortisol, and other neurotransmitters are still being studied."
"The hypothalamus affects the endocrine system and governs emotional behavior, such as anger and sexual activity. Most of the hypothalamic hormones generated are distributed to the pituitary via the
hypophyseal portal system.[SUP]
[11][/SUP] The hypothalamus maintains homeostasis; this includes a regulation of blood pressure, heart rate, and temperature."
http://www.youtube.com/watch?v=PMrPlCDGUwo
http://www.youtube.com/watch?v=PMrPlCDGUwo
http://www.youtube.com/watch?v=SS_qMHPI0XM
http://science.howstuffworks.com/environmental/life/human-biology/fear2.htm
http://learn.genetics.utah.edu/content/begin/cells/fight_flight/
http://www.ehow.com/list_6907783_parts-brain-involved-fight-flight.html