Our sense of self is one of the deepest and seemingly immobile expressions of brain activity. If something as innocuous as a magnetic field can change it, who are we, really? Drew Turney finds out more.
At some time during our toddler years, we start to understand that we’re a distinct person with free will and a constant internal monologue, distinct from everyone else around us, and (unless we’re struck with a neurodegenerative disease) our sense of self is the bedrock upon which we interact with the world for the rest of our lives.
But the sense of who we are is the result of neural activity, no different from less abstruse aspects of our personalities like whether we like broccoli or not. Deeper, self-referential philosophy about who we are might recruit more mental maps than the simpler stuff, but it’s all still just bioelectric sparks in the synaptic void.
Now imagine we could somehow isolate or read those neurological impulses that make up the dream you had last night, the memory of your first pet or your feelings for your spouse and even affect them.
In fact scientists already have – albeit in very basic terms. In 2015 researchers at the NIH/National Institute of Neurological Disorders and Stroke implanted a remote controlled device into the brains of mice that delivers drugs and can shine a light source on individual neurons.
The technology could not only reveal neural circuits very precisely, it let the scientists determine the path the mouse walked by – to some extent – controlling its behavior by turning neurons ‘on’ and ‘off’ at will using the light source.
Back in 2010 headlines were made by an even more sensational experiment when scientists at MIT induced mild electrical currents in the scalps of subjects using a technology called transcranial magnetic stimulation (TMS).
The currents slightly disrupted a brain region called the right temporo-parietal junction – not enough to destabilize the subjects’ sense of their personality, but when tested on their moral understanding of other people’s intentions, found their moral reasoning impaired.
Changing who you are
If such technology is possible, what else might we use it to alter? Could every aspect of our sense of identity – from our moral beliefs to our love of our families – be simply zapped by some machine, changing us into a fundamentally different person from the one we woke up as?
Dr James Giordano is Professor of Neurology and Biochemistry and Chief of the Neuroethics Program at Washington DC’s Georgetown University Medical Center, and he says technologies like TMS (transcranial magnetic stimulation) and TES (transcranial electrical stimulation) can certainly affect patterns of node and network activity of our brains. “[These technologies] can ‘induce ‘back and collateral propagation’ effects to alter the activity of linked brain networks that are involved in a number of cognitive and behavioral functions.”
However, he adds that the tools we have today tend to modulate activity of neuron networks rather than switch them on or off or generate them. “The analogy is that they function more like a dimmer switch to ‘adjust’, increasing or decreasing neurological nodes and networks that are in a particular activity state.”
In other words (thankfully so, many might think) that means we don’t have the technology to make you think of a boat when asked to picture a dog, make you a believer after a lifetime of atheism or convince you that killing is a good way to settle a dispute with a neighbour.
“Use of [these technologies] can affect the ‘disposition’ to visual imagery or be clearer in our interpretation of certain visual images, but not to imagine a specific object or event,” Giordano says. “That said, use of TMS can make us somewhat more susceptible to certain patterns of thought and emotion, and perhaps increase suggestibility. But current forms of transcranial neuromodulation can’t be used to completely alter existing beliefs or moral convictions or implant ideas.”
What the self is made of
But the very fact that precepts like moral judgment are subject to manipulation by external forces says something interesting about our sense of self. We tend to think of the more arbitrary mental characteristics like preferences for food or knowing the way to the supermarket to buy it as being less pivotal to our innermost nature.
Religious beliefs or our connection to family and friends – the stuff that makes us truly ourselves – feels much more deep-seated and harder to budge, so it must be made up of more neurons or more complicated neural maps (and therefore hard to manipulate with technology like TMS or TES), mustn’t it?
“To some extent,” Giordano agrees. “This centers on what brain scientist Greg Berns has termed ‘sacred values and beliefs’. It seems that certain cognition represent fortified patterns of neurological activity that have been developed and strengthened over time, and as a consequence of experience. They tend to be pretty durable, likely because they involve a number of convergent and co-active neural nodes and networks. But while they’re durable and relatively stable they can, in fact, be modified.”
But as Dr Ed Boyden points out, we’re still too far from knowing the ins and outs of how the brain really works to affect our personality that deeply. Currently head of MIT’s synthetic neurobiology group, and associate professor of the MIT Media Lab and the McGovern Institute, and the Departments of Biological Engineering and Brain and Cognitive Sciences, Boyden was one of the pioneers of using light to activate neurons.
“We lack a good understanding of how the brain represents and computes information,” he says. “Right now we don’t know how thoughts, emotions, and memories are represented in the brain.”
Besides that, Boyden points out that if we’re talking about neurons and neural maps changing, the idea that we’re the same person through our whole lives is an illusion of consciousness anyway.
Like all matter, human bodies and brains are subject to Theseus’s paradox, in which every component and plank of the ship of Greek myth is thought of as being the same ship even though every component and plank is gradually replaced. The sense of self might be cultural rather than biological, the constant expression of a primitive survival drive that actually shifts endlessly but gives us the illusion of permanence for the sake of psychological cohesion, not quite as unchanging and far more fallible than it feels.
“Actually our internal narrative is changing constantly,” Boyden says, “a lot of data shows the self is a reflection of the environment. But we shouldn’t confuse ‘changing’ with ‘fallible – in the face of a changing environment that demands we adapt, they might be opposites.”
Giordano calls it a form of ‘cognitive closure’ to ‘clump’ the qualities that define the sense of ‘me-ness’ we all have. “But should my brain be altered in some way via trauma or some kind of intervention that affects the pattern of the neural nodes and networks that are operative in my integrated sense of identity, then that sense of self might – and likely would – be disrupted, if not changed in some way,” he says.
Doing it yourself
But imagine the potential – and the potential double-edged sword. If we could use TMS, TCS or some other futuristic method to directly affect the inner workings of our cognition and affect memory and experience with enough finesse, we might be able to deploy a brain scanner and ‘edit out’ undesirable artefact, maybe curing PTSD or depression.
Or we might have a tool that can be switched on near an unsuspecting victim, generate uncontrolled rage directed at a third party and conveniently remove any moral resistance to violence or murder?
Consumer devices are already on the market, promising to make buyers think faster and sharpen attention. Electrical stimulation increased math performance in experiments conducted at Oxford University, after all. But scientists warn that using such devices yourself in such uncontrolled circumstances might bring about ‘unintended results’.
There’s an active forum on Reddit devoted to home TMS and TCS devices, and some users have already complained about burning to the scalp. One unfortunate who must feel like he’s trapped in a short story by Ray Bradbury or Isaac Asimov reported that he ‘seemed to be getting angry frequently’ after using one.
While hooking yourself up to a machine to get better study results and instead flying into a homicidal rage isn’t likely any time soon, it highlights one of the obvious limitations of any TMS technology. While certain brain regions are associated with certain functions, our knowledge of them is far from cut and dried.
Using a tool to soak a broad area of the brain in magnetism or electricity to target the patterns generated by individual neurons and neural maps seems like using a wrecking ball to tap a thumbtack into a cork board. How can we experience anything but the most general – probably vague – results?
“Could it be done more precisely and with greater finesse? Yes,” says Giordano. “Does the wrecking ball get the job done? Yes. Are there collateral and often non-specific effects? Often. Can you modify and/or mitigate these by directing the wrecking ball and metering its trajectory, location, speed and force? Sure can.
He says cognitive abilities and behaviours like memory an intentional states involve both convergent and divergent network activity that engage a fair amount of neurological real estate. “But that’s the core challenge – and opportunity – of non-invasive brain stimulation, to increase the specificity and precision of effect.”
It’s going to be interesting to see what happens with the burgeoning (and unregulated) field of consumer TMS and TCS kits if the above thesis is correct. Might it be possible to deploy one incorrectly and end up falling completely out of love with your spouse or hating your job for no reason other than swathes of synaptic connections were destructively reconfigured?
Continuing development in the technology in labs might lead to startling new research – and ramifications for theories about personal identity. Boyden can imagine a world where it’s possible to ‘upload’ specific thoughts or feelings into the brain from an external source by manipulating brain activity and says that at the rate the technology is improving we might see it within the next 50 years.
But he cautions that oversight will be crucial. “All experiments with brain stimulation on humans, and frankly any human subject experiments, must be approved by a panel who judges the ethics of the work. It’s important to take an ethical stand and make sure neurotechnology makes us who we want – as a society and a civilization – to be.”
One thing’s for sure. As our understanding of the way the brain works deepens, such technology will shine even more light onto many cognitive abilities and phenomena, including our seemingly-immutable sense of self.
Know your technology
TMS – transcranial magnetic stimulation uses a magnetic field generator or coil to target and stimulate small brain regions. Traditionally a medical treatment, it’s mostly used to measure the connection between the brain and muscles to evaluate damage from stroke, MS, motor neuron disease, etc. There’s evidence suggesting it might help neuropathic pain and major depressive disorders, but the risks include fainting and even seizures.
TES – transcranial electric stimulation (or tDCS, transcranial direct current stimulation) delivers a low level current straight to a targeted brain area using electrodes attached to the scalp. There’s some suggestion it can treat depression (although it’s even less proven that TMS) but the side effects can include skin irritation, nausea, headache, dizziness and itching under the electrodes.
However, news emerged recently from UC San Diego about new research. Using low-impulse electrical stimulation to the brain, researchers report significantly improved neural function in participants with mild traumatic brain injury.