Time travel seems like science fiction, but hundreds of scholarly papers explore the mind's capacity to go forward and backward in time. Welcome fellow space cadets!
[This is a guest Blog post by Professor Harry Whitaker who specializes in cognitive neuroscience, current and historical. It's Not My Fault, Blame My Brain is his monthly column for The Double Standard. His most recent book is Brain, Mind and Medicine: Essays in Eighteenth Century Neuroscience.]
As your mind time travels
From today to tonight,
Have you travelled faster
Than the speed of light?
Neuroscientists today seriously discuss mental time travel because some think it may be a uniquely human skill. The effort to distinguish ourselves from our primate relatives as well as other vertebrate contenders such as pigs, whales, and elephants for contender of highest-intelligence holder has a long, if checkered, history. To date, the most persuasive claim for our special status is language. Notwithstanding Orwell's Animal Farm, we have it and no other animal does.
Now comes a new contender for unique human ability: Mental Time Travel. Scientists today explain it as the ability of humans to project themselves backward in time to re-live events, or forward to pre-live them.
But imagine the paradoxes!
• I wasn't sure what time it was where I wanted to go—perhaps when I arrive I won't be there yet.
• Last week I time traveled, so I so I've already done my chores for today.
• When you mentally travel into the future, will you have amnesia for all the events you skipped?
Although recently a hot topic, Mental Time Travel actually has a past. The term was first coined nearly three decades ago by the experimental psychologist Endel Tulving. Recent scientific papers explore such things as how mind wandering (popularly called "day dreaming") often orients one toward the future, how brain damage in childhood can affect both the ability to recall the past and imagine the future, the relation between narrative language and mental time travel, and how transient amnesia that impairs a person's autobiographical memory raises the philosophical question of whether an independent "self" actually exists.
Tulving showed that memory is best understood as a group of different long-term versus short-term processes. Long-term types include episodic memory (for events), procedural memory (for knowing how to do things), and autobiographical memory (events that one has participated in). Mental Time Travel is clearly an autobiographical memory that encompasses past and future time. It intertwines with language, and may even depend on it; after all, where would we be without a "Been there, done that!" for the past, and "I'll do it later" for the future?
• Was Macbeth linguistically time traveling when he said, "Tomorrow, and tomorrow, and tomorrow / Creeps in this petty pace from day to day / To the last syllable of recorded time?"
• I was time travelling yesterday when suddenly it was tomorrow, which is today.
• Smart people only time travel to Saturdays and Sundays so they don't have to work.
• If you could time travel for someone else, think of all the people you could get rid of.
• I tried time traveling west really fast to see if I became younger, only to realize one has no compass when time travelling.
It is difficult to imagine mentally traveling through time without having words for past, present, and future. Yet not all languages express past and future tenses the way that English does. For instance, Hopi (northeastern Arizona, USA), Pirahã (spoken in Brazil, along the banks of the Maici River) and Amondawa (spoken in Brazil, near Jiparaná River) seem not to. As one researcher elegantly described it, the Pirahã speaker states whether he did or did not actually see something with his own eyes, or whether an event is either in his immediate experience or that of someone that he knows. For example, the English sentence, "[I] [am going to see] [The Time Traveler's Wife] [tomorrow]," might be translated into Pirahã as "[The Time Traveler's Wife] [is not] [in my immediate experience]."
Few studies so far consider Time Travel in the context of languages that don't speak of subjective time in the manner of English. That hasn't stopped some researchers from already challenging the claim that mentally traveling in time is uniquely human. Analyses of dog, pig, and chimpanzee behavior suggests that they, too, may possibly travel in time, not to mention elephants, porpoises and whales.
• If you mentally time travel while you are time travelling, you can simultaneously be in the past and the future.
• I was reading an article on time travel when I got ahead of myself.
• On an extended time travel journey, I met myself when I was a child.
• Mental time travel: the ultimate cure for agoraphobia.