Apparently, not many cat owners are aware of toxoplasmosis, a protozaon parasite that cats are the primary host for.
The parasites reproduces in the gut of the cat, the eggs are passed through the cat's faeces to other warm blooded mammals (such as rats, mice etc) which are then eaten by other cats hence completing the parasite's lifecycle.
Toxoplasmosis is known to change the behavior of some intermediary hosts. This includes slower reactions, attraction to cat urine and increased risk taking. This is all good news for the parasite as in the case of mice and rats this increases the likelihood of them being eaten by another cat and therefore continuing the parasite's lifecycle.
It's also worth noting that 30-60% of humans (such as cat owners) are infected with toxoplasmosis and those that are have an increased risk of traffic accidents.
In other words, if you find yourself strangely attracted to the smell of the litter tray and having more than your fair share of accidents, then maybe Mr Tiddles (or whatever name you call it) has been messing with your neurons.