The functions of the thalamus and midbrain include the regulation of consciousness, sleep and alertness. Occlusion of the artery of Percheron, for example by a clot, could result in a posterior circulation infarct impairing structures on both sides of the brain. This can produce a bizarre disturbance such as sleep from which the patient cannot be awakened.
^Percheron G (August 1973). "The anatomy of the arterial supply of the human thalamus and its use for the interpretation of the thalamic vascular pathology". Zeitschrift Für Neurologie205 (1): 1–13. doi:10.1007/BF00315956. PMID4126735.
^Agarwal N, Chaudhari A, Hansberry DR, Prestigiacomo CJ (January 2014). "Redefining thalamic vascularization vicariously through gerald percheron: a historical vignette". World Neurosurgery81 (1): 198–201. doi:10.1016/j.wneu.2013.01.030. PMID23314026.