You might have heard this one before, but a quick and admittedly cursory trawl through the archive didn't reveal it so here goes.
Jack is in his mid seventies and had his first stroke a decade or so back. Strokes are weird things. the mechanisms are clear, either a blood vessel wears thin and bursts, nuking the surrounding brain tissue, or a clot forms within or lodges in an artery depriving a region of the brain of oxygen long enough to kill it off. In either event a bit of brain stops working.
The thing is, depending on the bit of brain affected you can get weakness or paralysis in muscles (because of the way we are wired up the muscles affected will be on the opposite side of the body to the hemisphere of brain containing the injured bit). This can result in weakness or full blown paralysis, and in either event this might or might not improve over the next few days to weeks. Additionally, again depending on where the vessel was and how much damage was done, sensations can be affected, speech and thought processes can be affected, fits can be caused.
Poor old Jack had quite a bad one, and got a lot of these effects. His right arm and leg didn't work properly, and at times his brain even forgot they were there (a phenomenon known as "sensory inattention"), he struggled to find words and had bouts of quite severe agitation often lasting several hours.
It was clear even early on that he was hallucinated when he became agitated. Eventually he got enough words back to tell his family what he was seeing. And what he was seeing was a swarm of moggies, who had, quite uninvited, invaded the house and were roaming at will. He really couldn't understand why his family were letting them in to torment him like this, and so he got quite cross and began to lash out. Whether this was directed at the cats or the family who were around at the time was not clear. What was, was that he was really quite distressed and unsettled by his hallucinations. And quite unaware that is what they were.
In the end it became clear that these hallucinatory episodes were part of the aura of a variety of epilepsy triggered by the brain injury of the stroke. Treatment with anti-epileptic drugs has really helped reduce the frequency and severity of his attacks and they are now much more manageable, to everyone's relief. However, in the interim the family hit on a novel solution to his distress. They bought him a dog. A big, fluffy cuddly toy English Shepherd. The brute is near life size and holds pride of place on the sofa beside him.
And he helps scare away the cats.