Researchers have found that acupuncture is able to assist with the problem of post-stroke insomnia, and it does so by reducing hyperactivity in the sympathetic nervous system.
Fifty-two hospitalised stroke patients with insomnia, were randomly assigned to receive either real acupuncture for three days, or sham acupuncture as a control. There was greater improvement in the group receiving real acupuncture, but additionally, measures of autonomic nervous system functioning (blood pressure and heart rate variability) suggested that sympathetic nervous system hyperactivity was reduced in the real acupuncture group.
(Intradermal Acupuncture on Shen-men and Nei-kuan Acupoints Improves Insomnia in Stroke Patients by Reducing the Sympathetic Nervous System Activity: A Randomised Clinical Trial. American Journal of Chinese Medicine 2009.)