"Ultimately, it's Warren's engaging first-hand experience that brings all this to life". " You'll never look at waking, sleeping or dreaming the same way again."
"Full of sentences that make you stop and consider daily experiences from a different angle. It struck a powerful chord with me."
"Head Trip almost reads like an Oliver Sacks essay turned inside out; instead of rare neurological cases, we get the standard-issue noggin, which turns out to be every bit as exotic."
"It never occurred to me that you could write a travelogue about your own mind.…Head Trip [is] an entirely original and completely fascinating tour through the myriad states of human consciousness....A rich blend of research, theory, and personal encounter."