Everyone gets a little paranoid sometimes, but with politicians and presidential candidates lobbing warnings about the threat of terrorism left and right, it can be hard to know when to stop worrying. But as psychologist and author David J. LaPorte explains in his book, Paranoid: Exploring Suspicion from the Dubious to the Delusional paranoia can take on many forms and wriggle its way into even the most trusting minds. On this edition of Please Explain, LaPorte answers your questions on the psychology and neuroscience of paranoia and how the uncertainty of the post-9/11 world makes it easy for paranoia to set down roots.

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