A friend and fine modelmaking colleague, Iain Robinson has written a very important and interesting post on his superb blog about the link between solvents and depression, lethargy, loss of mojo, etc.
It's officially known as neurotoxicology and is a fact. of course how it may affect different individuals changes from person to person, but the number of complaints of the above symptoms I see on forums must be a little more than simple burnout.
Please read all Iain's latest post AND the very interesting and informative comments to the post on :-
I think you may be alarmed and surprised.
I think, fortunately that I have got away with it so far, though my periodic depressions may well have coincided with a larger than normal exposure to solvents. If I had half a memory I could maybe make the correlation.