[pfflier]

Watching these videos it appears to me that she could be having a petit mal seizure while she is using the bollard for support. If you watch the first few seconds she is spasming rythmically. Her staff must be familiar with the symptom pattern or they wouldn't have left her with only one member supporting her (on the left).

Epileptics I know can tell when a seizure is starting to onset. They cannot walk several yards though because the onset is pretty quick. Everyone is different though.

Anti seizure medications (benzodiazepine) is effective if autoinjected into the thigh.

Could the falling object be associated with an injector?

http://www.health.harvard.edu/blog/quick-injection-helps-stop-epileptic-seizures-201202234319

[Abathar]

Low blood pressure can do the exact same thing also, I know this for a fact because I kept having stroke symptoms and would lose the use of the left side of my body. Scared the poop out of me, when I went off blood pressure meds it went away. I would do exactly what she did, because I lost the use of the left leg so I would dip up and down like she is in the video.

[skippermd]

The coughing fits with this too— if she is on keppra (an anti seizure med) it has a well known side effect of a bad dry cough...