Interesting bit from Wikipedia about the effects of getting choked out like this dude:

The American Neurological Association's study entitled “Syncope: A videometric analysis of 56 episodes of transient cerebral hypoxia” observed the effects of cerebral hypoxia on 42 test subjects who completely lost consciousness. Their syncope state lasted 12.1 seconds, plus or minus 4.4 seconds. Muscle jerks occurred in 90% of patients. The most common pattern of movement consisted of multifocal arrhythmic jerks (uncoordinated spasms of multiple muscle groups) in both proximal and distal muscles. Additional movements also occurred such as: righting movements (if the patient had slumped one way while falling asleep they woke up and immediately corrected, if not overcorrected), oral automatisms, and head turns. In most of the patients their eyes remained open. Sixty percent of the patients reported having visual and auditory hallucinations.[7]