And et, over 50 years of research by Csikszentimalyi and his colleagues show that in the majority of people, the happiest moments of their lives - those in which they are spontaneously, joyously effortless in flow, in the zone, in tune with the world around them, is when they are working at things they love - this includes scientists who may engage in 8 or more hours of intense thinking a day.

Repeated studies also show that apart from exercise, challenging your mind with complex cognitive tasks for long periods of a time is immensely protective AGAINST Alzheimers and other forms of cognitive decline.

So does this disprove the study in the article? No, it confirms it.

If you have to use your thinking mind for hours in way that involves controlling your attention, pushing yourself to stay on a task you intensely dislike, it can be harmful to your brain.

if your attention flows naturally to a subject you love, the more hours you think about it the healthier your brain will be.

So the question naturally comes up - what if my job inolves thinking a lot about things I don't like?

"If you can't be with the one you love, love the one you're with."

Similarly, if you can't think about things you love, learn to love the things you have to think about.