Executive summary
Our perception of reality is more fluid than we tend to believe. When we drift off to sleep, our brain creates entire worlds perceptually indistinguishable from reality, and even our most treasured memories are really just our minds’ reconstruction of past events. This fascinating ability of the brain to create and alter our perceived reality has driven scientists to explore whether these mental processes could be artificially influenced.
- Several companies have already developed devices that they claim gives people some control over their dreams.
- “I have no doubt that dream engineering could open many minds, heal others and help us to understand one another more clearly,” says Adam Haar Horowitz, a researcher at MIT Media Lab.
- Multiple studies have demonstrated it may be possible to edit, erase, or implant memories in animals.
- “The proof of principle is there already,” says Steve Ramirez, assistant professor of psychological and brain sciences at Boston University. “I think the question is more of when would it make sense to do that? Or when would it make sense to artificially activate or inactivate or erase memories in people?”
- Scientists are exploring the possibility of uploading the human mind onto a computer, although the brain’s complexity presents a formidable obstacle.
- “If the body is crucial for self-consciousness, then it follows that a mind uploaded to a supercomputer could never gain consciousness because it will be nothing more than a disembodied virtual brain,” says science writer Moheb Costandi.
The ability to influence our dreams, heal traumatic memories, or even digitise consciousness could revolutionise how we experience life itself. At the same time, it raises some serious ethical concerns we cannot afford to ignore. We need to move forward thoughtfully, asking ourselves not just whether we can develop these technologies, but whether we should.
Can you really trust your perception of reality? Think about it for a moment: right now, you probably feel pretty sure about what’s real and what isn’t. Yet each night when you drift off to sleep, your brain conjures up entire worlds, complete with sights, sounds, and even physical sensations that feel absolutely real… until you wake up. And it’s not just dreams. Every memory you have, no matter how vivid, is just your brain reconstructing past events – a mental simulation that might not be as accurate as you think. When you remember your last birthday or your first kiss, you’re not actually experiencing those moments again – you’re experiencing your brain’s interpretation of them.
So if our brains can naturally create such convincing false realities, is it so far-fetched to think that we could someday develop technology that could accomplish the same thing? Believe it or not, we’re already making some progress in that direction. Neuroscientists have gotten pretty good at decoding brain signals in recent years – good enough to translate them into commands for moving computer cursors or robotic limbs. But sending signals back into the brain? That’s where things get tricky. To create truly convincing artificial experiences our mind would perceive as real, we’d need to know the precise function of each individual neuron in our brain and how they work together to create our perception of reality. How difficult could that be? Let’s find out.
How immersive technologies manipulate reality
Immersive technologies like AR and VR have proven very effective in manipulating our sensory perception, even if only temporarily.
In a way, we can already manipulate reality through immersive technologies like augmented and virtual reality (AR and VR). Our experience of the world is ultimately a product of our senses; our eyes pick up light, our noses detect chemical signals in the air – you get the picture. All of this information is then processed by our brains to create our perception of reality. When you put on a VR headset or AR glasses, you’re essentially allowing technology to override what your eyes and ears would otherwise perceive. While AR and VR still have certain limitations – the resolution isn’t quite perfect, there’s still some lag, and the field of view is limited – users often become so deeply immersed in virtual environments that they briefly forget they’re experiencing an artificial world.
The experience can feel so realistic that the user will reach out to touch a virtual object or flinch when something flies toward their face in VR. These instinctive reactions show how readily our brains can accept artificial input as real. Of course, the illusion maintained by AR and VR remains tethered to external hardware – remove the headset or glasses, and the real world reasserts itself instantly. However, the kind of direct neural interface technology we’re talking about in this article goes a step further than a mere visual overlay. Instead of placing screens in front of your eyes or speakers near your ears, it would bypass your physical senses entirely, creating experiences by directly stimulating your brain’s sensory processing centres.
“I have no doubt that dream engineering could open many minds, heal others and help us to understand one another more clearly.”
Adam Haar Horowitz, researcher at MIT Media Lab
Take control of your dreams
Scientists have demonstrated that it may be possible to insert content into people’s dreams and even control their direction. But is this such a good idea?
We spend a huge portion of our life sleeping – about a third of it, in fact. That’s because sleep is a very important thing: in addition to giving our brain the time it needs to process the day’s information, it also enables our body to rest and recuperate from daily exertion. Of course, when we’re sleeping we usually enter a dream state. Often those dreams can be very pleasant, but sometimes they can be downright terrifying.
Whether you’re experiencing a blissful fantasy or a horrific nightmare, all dreams have one thing in common – they’re largely beyond our conscious control. When we dream, we’re essentially passive observers in a story created by our subconscious mind. We can’t choose to dream about flying instead of falling, or transform a frightening scenario into a pleasant one. We can’t decide to explore specific locations or interact with particular people. The narrative has always unfolded independently of our conscious desires – until now, that is. Around the world, research teams have been hard at work trying to give us a little bit more control over our dreaming lives.
A dream within a dream
Back in 2020, a team of researchers from MIT Media Lab discovered it might be possible to insert ideas into a person’s mind while they sleep and thus manipulate the contents of their dreams. During the study, participants were asked to wear a sleep tracker called Dormio and record some simple audio prompts, such as “remember to think of a tree”, before going to bed. As they drifted off to sleep, the tracker would monitor various physiological markers – heart rate, electrical changes on the surface of their skin, and finger movements – to identify when participants entered hypnagogia, a transitional state between wakefulness and sleep when the mind is more receptive to external stimuli.
Once the tracker determined that the person has entered this sleep stage, the device would play the prompts back to them in an attempt to influence what they dream about. And it actually worked! According to researchers, as many as 67% of participants reported having dreams involving a tree. While this obviously doesn’t offer definitive proof that it’s possible to control dreams, it does suggest that the whole idea may not be entirely far-fetched.
More recently, US-based startup Prophetic announced plans to launch a device named the Halo, which purportedly enables anyone to take control of their dreams. Shaped like a headband, the device is worn on your head during sleep and uses a combination of EEG sensors and high-frequency ultrasound waves to monitor the user’s sleep patterns and induce a dreamstate known as lucid dreaming. In this type of dream, which occurs spontaneously during the REM stage of sleep, the person is aware that they are dreaming and may sometimes even be able to influence what happens in the dream. While this isn’t something that happens on a daily basis, it’s estimated that around 70% of people will experience at least one lucid dream over the course of their lives.
Earlier research has also shown that lucid dreaming may have some real-world benefits. For example, a study conducted at the University of Bern in Switzerland found that participants who practised flipping coins into a cup in lucid dreams demonstrated a significant improvement in performance the next day, as opposed to the control group which showed no improvement. According to the company, by inducing a lucid dreamstate, the Halo could enable users to exercise their creativity, explore new ideas, or even solve real-world problems in their sleep.
Hijacking the world of dreams
As enticing as this all may sound, you probably shouldn’t rush to give it a try just yet. While the technique doesn’t require a brain surgeon to open up your skull – unlike some others we’ll mention later – we still don’t know whether prolonged exposure to high-frequency noise might lead to unwanted side effects or affect our mental stability. We already know sleep plays an important role in our overall health and wellbeing, so altering the natural course of our dreams could disrupt that purpose, leading to serious consequences. “We are very rarely lucid in our dreams,” explains Mark Blagrove, a sleep scientist based at Swansea University. “And not being lucid may be part of, or required, for any effective function of dreams.”
Another possibility that we cannot afford to ignore, however remote it may seem now, is that the technology may be exploited by unscrupulous companies or cyber criminals. The 2021 Future of Marketing study published by the American Marketing Association New York found that 77% of marketers plan to use dream incubation to inject advertisements into our dreams in the near future. There is also the risk that nefarious actors may use the technology to influence a person’s political leanings or feelings towards other people. “I have no doubt that dream engineering could open many minds, heal others and help us to understand one another more clearly,” says Adam Haar Horowitz, a researcher at MIT Media Lab. “It could also become an advertising gimmick. We have to proceed with caring and watchful eyes.”
“The proof of principle is there already, that we can do it. I think the question is more of when would it make sense to do that? Or when would it make sense to artificially activate or inactivate or erase memories in people?”
Steve Ramirez, assistant professor of psychological and brain sciences at Boston University
The mystery of memory itself
While the exact workings of the human brain are still shrouded in mystery, researchers are getting closer to being able to manipulate our memories.
The human brain ultimately remains one of science’s greatest mysteries. Despite significant advancements in neuroscience, we still lack a deep understanding of many of its most fundamental processes. How does your brain create a memory? How does it store it? And how does it pull up that specific memory later when you need it? Researchers continue to work hard to uncover these mysteries. While the picture obviously remains far from complete, they have made remarkable progress over the years, taking us one step closer to figuring out exactly how these complex mechanisms work – in animals, at least.
In 2009, researchers at the University of Toronto found a way to selectively erase fearful memories in mice by targeting their amygdala – the part of the brain responsible for processing emotions – with a toxin. Then in 2014, MIT researchers did something even more astonishing: they successfully implanted false memories in mice, making them believe they had experienced an electric shock in a particular environment even though it never actually happened. More recently, in 2017, a team of researchers from Columbia University and McGill University showed that it might be possible to neutralise the triggers associated with a traumatic memory in snails without disrupting the memory itself by blocking the function of a specific protein that plays a role in the formation of long-term memories.
Say goodbye to bad memories
While these techniques haven’t yet been translated to human applications – our brains are far more complex than mice brains, after all – the underlying principles suggest similar approaches could eventually work in people. “It’s not something that we can do on a whim in people the way that we do it in mice nowadays. But I don’t think that it also breaks any law of physics to say that it will be a possibility, if not an inevitability, in people one day, probably within our lifetime,” argues Steve Ramirez, assistant professor of psychological and brain sciences at Boston University. “So the proof of principle is there already, that we can do it. I think the question is more of when would it make sense to do that? Or when would it make sense to artificially activate or inactivate or erase memories in people?”
It doesn’t take a degree in neuroscience to understand why something like this might be helpful, particularly for those suffering from severe PTSD and other trauma-related disorders. Such conditions can affect the person long after the initial trauma, presenting as a series of debilitating symptoms including nightmares, flashbacks and panic attacks. Having the ability to selectively modify or dampen traumatic memories could offer life-changing relief for these individuals. Furthermore, understanding how memories work could also benefit people on the other end of the spectrum – those losing their memories to conditions like dementia, or amnesia. If we can figure out how memories are created and stored, we might be able to help people hold onto them better or even recover the ones they’ve lost.
Could your memory be hacked?
Naturally, the idea of memory manipulation raises a variety of ethical and medical concerns. Indeed, traumatic memories can serve crucial evolutionary and psychological purposes. They help us learn from past experiences, avoid dangerous situations, and shape our personalities. Interfering with these natural mechanisms could have unforeseen consequences on human behaviour and development. “It is not a great idea to do ‘cosmetic memory surgery’ and try and erase slightly embarrassing memories,” says Sheena Josselyn, memory researcher at the Josselyn Frankland Lab. “For instance, it is the memory of how embarrassed I was the last time I tried karaoke that keeps me from doing it again! So even aversive memories are important. Some believe we are the sum total of our memories and that messing with memories changes who we are.”
There are also legitimate concerns about potential adverse psychological effects. Suppressing traumatic memories might lead to increased anxiety, panic attacks, or even more complex psychological conditions like dissociative identity disorder. The human psyche is delicate and interconnected – altering one aspect could trigger a cascade of unintended consequences. As brain-computer interfaces continue to develop, we also need to consider the possibility that authoritarian governments may exploit the technology to erase history or influence people’s thoughts and behaviour. It could even become a powerful tool in the hands of hackers, who could use it to hack into people’s minds and steal sensitive information or threaten to erase their memories if they don’t pay a ransom.
Moreover, like many advanced medical technologies, memory manipulation might become available only to those who can afford it, further widening the gap between social classes. The wealthy could potentially erase traumatic experiences or enhance their memories, while others remain trapped with their psychological burdens, creating yet another form of social inequality. “If we do get general cognitive enhancers that everybody can take, there isn’t going to be equal access to those drugs,” says Richard Huganir, director of the department of neuroscience at the Johns Hopkins University School of Medicine. “They’re gonna cost money and so of course they won’t be very equitable.”
“We don’t know what it would be like to potentially live forever in a digital form or a downloaded form of a digital body. What if there’s nobody else there, something goes wrong and it’s just you wandering in a dark and lonely wasteland?”
Angela Thornton, researcher at the University of Nottingham
Keep your head in the cloud
Recent advancements in brain-computer interfaces have opened the door to the possibility of digitising human consciousness and uploading our minds to the cloud. Could digital immortality truly be feasible?
During a Neuralink presentation back in 2020, Elon Musk (in typical fashion) made a bold claim – that humans will one day achieve immortality by uploading their brains onto computers. “In the future, you’ll be able to save and replay memories,” he remarked. “You could potentially download them into a new body or into a robot body.” As preposterous as it may sound, the premise behind the whole mind-uploading idea is relatively sensible. Since the brain follows the laws of physics like any other natural system, with enough computing power, we should be able to accurately simulate it in software, effectively recreating a person’s mind in digital form. Sounds simple enough, right? Well, not exactly.
The human brain contains over 85 billion neurons, which form approximately 100 trillion neural connections between each other. And those connections are basically what makes you… you. Your memories, your fears, your personality quirks – they are all encoded in those connections. So, in order to accurately simulate your mind on a computer, we’d need to find a way to replicate every single one. To put the immensity of this challenge into perspective, scientists have only recently managed to create a complete 3D model of a fruit fly larva’s brain, which contains roughly 3,000 neurons and 500,000 connections. It might be decades, or even longer, before we can do the same with the human brain.
How is consciousness formed?
Even if we managed to map every single connection in your brain and simulated it, there’s no guarantee that it would produce consciousness. Despite decades of research, our understanding of how consciousness forms remains remarkably limited. Some cognitive scientists argue that the conscious mind emerges naturally from the brain’s neural structure, suggesting that a sufficiently accurate brain simulation would spontaneously generate conscious experience. Others contend that consciousness requires bodily awareness and physical embodiment – that a disembodied digital mind simply couldn’t be conscious in any meaningful sense. “If the body is crucial for self-consciousness, then it follows that a mind uploaded to a supercomputer could never gain consciousness because it will be nothing more than a disembodied virtual brain,” says science writer Moheb Costandi.
Let’s assume for the sake of the argument that the first group is right, and we manage to create a conscious digital copy of your mind. Then what? Would we exist as some kind of disembodied consciousness floating through digital space? What if the digital replica were running while we were still alive? How can “you” be conscious in two modes at the same time? Or would we transfer our minds into robot bodies, as Musk envisioned? Could a mind accustomed to physical embodiment adapt to a completely different mode of existence? “There’s a lot of freedom that goes with that idea,” says Angela Thornton, a researcher at the University of Nottingham. “But there’s also quite a big adjustment, in terms of your brain and your mind coping with the fact that the shell you’re in is completely different.”
Upload your brain
One company has already taken the first step towards this future. A US startup called Nectome claims that it has developed a biological preservation technique that will enable us to preserve the brain so that it can be later uploaded onto a computer once we develop technology capable of achieving such a feat. If you think this sounds too good to be true, you may be right. As it turns out, the procedure has a 100% death rate. Named vitrification, it involves injecting a chemical solution into the big carotid artery in a person’s neck while they are still alive, which turns their brain into glass and preserves its neuronal structure. The idea behind the whole process is that preserving the brain’s structure down to the last neuron would one day enable us to extract memories from the tissue and re-create the person’s consciousness.
The only problem – in addition to the procedure being fatal, that is – is that we don’t know whether any of it is possible. We don’t know how long memories can survive in dead tissue, whether it’s possible to retrieve them, or whether consciousness can be restored even if we could do the first two things. This won’t stop the company’s founder Robert McIntyre from trying, though. In fact, he is convinced that his work will have a profound impact on our society. “It will create a whole new history and change society, I think, as profoundly as writing did”, he says. “We’ll then be living in the era of living memory. Humanity won’t really forget things like it does right now.”
Digital immortality
While the idea of living forever through digital means may sound alluring, it also raises some serious ethical concerns. For one, digital immortality would profoundly affect how we process death. When someone ‘dies’ but continues to exist in digital form, how do loved ones cope with this ambiguous loss? The traditional stages of grief might become complicated by the presence of a digital version of the deceased – someone who is simultaneously gone yet still accessible. For those undergoing the digital transition, the psychological implications are equally complex. How does one process the death of their physical form while maintaining consciousness? The trauma of watching one’s biological body cease to function, while continuing to exist in a virtual realm, could be psychologically devastating.
Then there’s the matter of trust. When you upload your mind, you’re essentially handing your entire being over to whoever controls the servers. We’re already worried about companies harvesting our browsing history – now imagine giving them your complete consciousness. What if they decide to use your neural data in ways you never agreed to? What if someone hacks in and finds ways to torture your digital self? Even scarier, what if you decide you’ve had enough of eternal life, only to discover there’s no delete button? “We don’t know what it would be like to potentially live forever in a digital form or a downloaded form of a digital body”, adds Thornton. “What if there’s nobody else there, something goes wrong and it’s just you wandering in a dark and lonely wasteland?”
The socioeconomic implications are particularly concerning. If this technology follows the usual pattern, it’ll start out expensive and exclusive, which means it would be available only to the wealthy and powerful. “Are we going to have a new form of inequality where people who have access to immortality are people of financial status?”, asks Francois Zammit, philosophy lecturer at the University of Malta. “What about certain politicians? Let us suppose an authoritarian state where the ruler becomes digitally immortal and they keep running the country for eternity. What are the ethical implications of that?” Perhaps it’s best that we never find out.
Learnings
So, what’s the big takeaway? Are we truly on the verge of conquering the final frontier: the human mind itself? While neuroscience has made remarkable strides in understanding brain function – mapping neural networks, decoding brain signals, and developing neural interfaces – the brain remains shrouded in mystery. The truth is, we may never fully comprehend how billions of neurons create the experience of being human. But this uncertainty shouldn’t stop us from exploring the possibilities ahead.
Having the ability to control our dreams, manipulate our memories, or transfer our consciousness into a digital realm could transform mental health treatment, revolutionise learning, and even reshape our relationship with mortality. PTSD sufferers could finally find peace. Students could master subjects while sleeping. The elderly could preserve their memories before cognitive decline sets in. Yet these enticing possibilities also raise some profound ethical questions. Would selectively editing memories change who we are? Could dream manipulation rob us of our last truly private space? And does digital immortality strip death – and therefore life – of its meaning?
