Howard has seen up close how Arteta is careful about the public persona he wants to portray.
He wrote for the Daily Mail: "I have interviewed him a few times as a manager and every time, before the cameras start rolling, it has just been like the old days; he calls me Timmy, there's a lot of smiling and giggling.
"It's all very casual. It's the Mikel I shared a dressing room with.
"But then the interview starts, he goes into game-mode - and he has to be the person that he wants to portray. That's not my friend. That Mikel the manager. He has changed.
"When I first got to Everton, he was one of Moyes' Crown Jewels. He was far and away our best footballer. He was a really good guy and a really engaging guy. But Mikel was always somebody who took football very, very seriously. There was never an off day."
Howard added: "He was meticulous in the dressing room, in the canteen, and on the bus. He was always studying film or talking tactics. He was someone to look up to, to mirror your lifestyle on."
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