Below is an excerpt I thought was interesting. Though it only comments on the person acting out the persona, it doesn't offer any insight/effect re who is on the other end.
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The urge to act out an entirely different persona is widely shared across cultures as well, social scientists say, and may be motivated by curiosity, mischief or earnest soul-searching. Certainly, it is a familiar tug in the breast of almost anyone who has stepped out of his or her daily life for a time, whether for vacation, for business or to live in another country.
"It used to be you'd go away for the summer and be someone else, go away to camp and be someone else, or maybe to Europe and be someone else" in a spirit of healthy experimentation, said Dr. Sherry Turkle, a sociologist at the Massachusetts Institute of Technology. Now, she said, people regularly assume several aliases on the Internet, without ever leaving their armchair