How erasable do they think our memories are? Are we already meant to have forgotten the original Total Recall and its career-best performance from Arnold Schwarzenegger as someone whose secret agent dreams may have more substance than his humdrum reality?

It’s barely 20 years since Paul Verhoeven’s freewheeling adaptation of David Cronenberg’s reworking of Philip K Dick’s story, We Can Remember It For You Wholesale, became an instant sci-fi classic. So why the remake with Colin Farrell and Kate Beckinsale that’s just been released? And why now?

Given that much of the 1990 Total Recall unfolds on Mars, it’s tempting to find  significance in the new film having had its US release within days of Nasa successfully landing their largest ever rover, Curiosity, on the Red Planet. The only tiny problem with this theory, and one of several big problems with the remake, is that this time round there’s no Martian action. Maybe they didn’t have the budget to go there.   

Which brings us to the reason why anyone should try – and in this case fail – to improve on a movie that revels in the bizarre possibilities of  waking up to find your memories have been altered and you are not yourself.

The denizens of Hollywood’s dream factory have always been attracted to tangled tales of life as a fairground hall of mirrors, of boundaries blurred between what’s real and illusion, of virtual realties. True lies, as Arnie himself might put it. Total Recall is one of the wild cards in a pack which – off the top of my not-entirely-reliable head – includes Inception, Memento, Vertigo, Spellbound, Fight Club, A Beautiful Mind, Identity, The Matrix, The Truman Show, Eternal Sunshine of the Spotless Mind, eXistenZ, Long Kiss Goodnight,  Brazil and Dark City.      

There are hundreds more, even if you don’t count all those horror films that attempt to inject a quick fix of thrills using dreams, dream-within-dreams and movies-within-movies.  But there’s one film, which more than any other I know,  provides an unexpected inside-our-minds insight into why these kind of cinematic “reality checks” remain so compelling and popular.  And it’s a documentary about climbing.

Brain riddle

Touching the Void follows two mountaineers on a near fatal 1985 expedition in the Andes.  The 2003 documentary used dramatised scenes with the original climbers playing themselves. There’s a sequence, not in the original release but among the DVD extras, where one of them – dressed in the gear he’d been in when he broke his leg and was later left for dead – starts to freak out. He begins to think he’s still on the original expedition trying to crawl back to base camp, and that everything that’s happened in the last 18 years is just a figment of his imagination, a fantasy his mind has created to comfort himself as he loses the battle to survive.   

It’s a chilling moment – emphasised later when he angrily tells the crew: “Do you have any idea how bad it was? ... I died here!" For all the fictional examples of someone flipping between alternative realities, it’s the only instance I know where you can see it happen to someone who is a person, not a character. It shows how tenuous our grasp can be of where, when and even who we are. We continuously assemble our own universe and position ourselves in it based on our memories, our sense of self and what we are currently perceiving. Change enough of those inputs and we can switch from one version of events to another if it seems more plausible.

Most of us have experienced low-level versions of this when we wake up, perhaps in a strange bed, possibly hung-over, and briefly struggle to come up with a coherent story that fits all the known facts. It helps explains phenomena like false memories, déjà vu, or confabulation, where we effectively lie to ourselves about our own lives.

But the trickier issue isn’t why we can occasionally lose our bearings.  It’s how we are consistently able to keep them. What enables the vast majority of us to develop an identity and to maintain it even though we have this nasty habit of plunging into unconsciousness every night?   How can each of us be sure the “me” that wakes up is the same as the “me” that went to sleep? Is there any way to reliably tell whether what we see and feel and remember is real rather than illusion or delusion? 

There’s much fun to be had – as well as a lot of heavy duty philosophy, metaphysics and epistemology to wade through – wrestling with such easy-to-ask, fiendish-to-answer questions. And even if we get past them, or at least put them to one side, that still leaves us with what’s going on within ourselves to enable all these experiences and perceptions (and deceptions) to be integrated into something, someone, with a sense of themselves.  

We are still a long way from developing a widely agreed neuroscience of consciousness, with many researchers shying away from an area so overshadowed by philosophy and riddled with subjectivity.  There are all sorts of theories from it arising from high-frequency resonances between different regions of the brain, to it being a form of quantum computing taking place on an atomic scale in microtubules in neurons across the brain and possibly beyond.    

Some of the current thinking on this would blow your mind – if only, as we’ve established, it weren’t so tricky nailing down what we mean by “mind”. And by “your”.  What we can under the circumstances be reasonably sure is true is that for all our scientific understanding of ourselves and our brains, we remain very hazy on how our selves and our brains fit together.   

It’s not something we tend to think about... except perhaps fleetingly on those mornings we wake up disoriented in a strange bed having had one drink too many.  Or when a movie deliberately messes with our head.

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