For example, during sympathetic activation the resulting tachycardia is usually accompanied by a marked reduction in total power, whereas the reverse occurs during vagal activation.

In a similar manner, sympathetic activation with parasympathetic inhibition allows the baroreflex to elevate blood pressure.

Therefore, the chronic sympathetic activation associated with iron deficiency should result in increased cardiac output.

Behavioral changes can be smoking, alcohol consumption, eating and exercise, and physiological changes can be changes in sympathetic activation or hypothalamic pituitary adrenocorticoid activation.

Sensory afferent nerves trigger a systemic sympathetic activation leading to marked vasoconstriction.

The patient may become agitated, sweaty, weak, and have many symptoms of sympathetic activation of the autonomic nervous system resulting in feelings akin to dread and immobilized panic.

Administering a 5% sugar solution peri- and postoperatively usually achieves a good balance between starvation reactions and hyperglycemia caused by sympathetic activation.

"In today's world, sympathetic activation usually occurs in response to emotional stress, but our body prepares as if it were responding to a physical threat," the doctors wrote.

However, repeated arousals in individuals have clearly been shown to be related to sympathetic activation and elevation in blood pressure.

For example, both reactions exhibit brainstem control, paralysis, sympathetic activation, and thermoregulatory changes.