Apple CEO Steve Jobs has been called a "hypomanic" by assistant psychology professor John Gartner.

Speaking to Fortune Gartner describes the characteristics of entrepreneurs, such as Jobs. "Many entrepreneurs are so driven they alieneate others", he said, adding that they may be unable to "control their behaviour".

"We've read about them over and over again. An entrepreneur founds a wildly successful business and then is forced out, because he's alienated those who work with him," Fortune writes.

The hypomanic gene

Gartner is an assistant professor at Johns Hopkins Medical School in Baltimore. His new book, "The Hypomanic Edge: The Link Between A Little Craziness and A Lot of Success in America" argues that it's not just lack of management training that affects the behaviour of entrepreneurial visionaries, it's also that they are, "not wired to be managers". They are hypomanics.

Hypomania is defined as: "A condition similar to mania but less severe. Hypomanic episodes may resemble manic episodes in symptoms. But hypomanic episodes do not cause significant distress or greatly impair one's work, family, or social life while manic episodes do."

"Creative, impulsive, abrasive"

Gartner also runs a website for hypomanics. There he reveals the characteristics of the breed. "Hypomanics", he writes, "can be creative, confident, and productive, and for that reason are disproportionately represented among the overachievers of almost every field."

However, hypomanics can also be, "impulsive, act without thinking, try the most improbable schemes, and fail in the most dramatic and silly ways". They can also be, "arrogant, impatient and irritable".

Reality distortion

"They have an offbeat idea, which they believe with messianic fervor will change everything," Gartner says. "And their evangelical zeal gets other people on board."

Jobs' single-minded focus ("reality distortion field") drove Apple to revolutionize computing in the 80's - but his abrasive attitude also led to his eventual ousting from the company he co-founded. Gartner reflects that this history hints of a hypomanic edge to the mercurial Apple CEO.

Gartner believes that many entrepreneurs share similar qualities to religious visionaries. They "don't think outside the box, because they don't even see the box," he told Fortune.