An article on the "Sensed-Presence Effect" appears in the April 2010 issue of Scientific American, the prestigious popular science and technology magazine. In the article, writer Michael Shermer cites The Third Man Factor, calling the book "gripping". Shermer also outlines some possible explanations for Third Man reports, some of which are discussed in the book, and some of which are not:

"I suggest four explanations: 1) The hallucination may be an extension of the normal sensed presence we experience of real people around us, perhaps triggered by isolation. 2) During oxygen deprivation, sleep deprivation or exhaustion, the rational cortical control over emotions shuts down, as in the fight-or-flight response, enabling inner voices and imaginary companions to arise. 3) The body schema, or our physical sense of self-believed to be located primarily in the temporal lobe of the left hemisphere-is the image of the body that the brain has constructed. If for any reason your brain is tricked into thinking that there is another you, it constructs a plausible explanation that this other you is actually another person-a sensed presence-nearby. 4) The mind schema, or our psychological sense of self, coordinates the many independent neural networks that simultaneously work away at problems in daily living so that we feel like a single mind."

Read the article here.