Imagine playing a piano with just your thoughts. Now imagine the device reading your brain knows what you’re about to play before you consciously decide to.
Thank you for reading this post, don't forget to subscribe!This isn’t science fiction. It happened to Nancy Smith.
After a devastating car accident in 2008 left her paralyzed from the neck down, Smith became a pioneer in brain-computer interface (BCI) research. Scientists implanted a device that allowed her to play music again by simply imagining the keystrokes. But something unexpected happened that should make all of us pay attention.
“It felt like the keys just automatically hit themselves without me thinking about it,” Smith said. “It just seemed like it knew the tune, and it just did it on its own.”
Her BCI wasn’t just reading her conscious thoughts. The system detected her intention to play hundreds of milliseconds before she consciously attempted to do so, according to neuroscientist Richard Andersen at Caltech who led the trial.
Welcome to the new frontier of privacy invasion: your pre-conscious thoughts.
What Makes This Discovery So Troubling
Most people understand that technology can track what we do online. Fewer realize that brain-computer interfaces can now access the thoughts we haven’t even formed yet.
Smith had an extra interface implanted in her posterior parietal cortex, a brain region associated with reasoning, attention and planning. This dual-implant setup allowed researchers to capture not just motor commands, but the planning stages that happen before conscious awareness.
Think about what this means for a moment.
Your brain starts preparing actions before you’re aware of deciding to take them. BCIs can now tap into this pre-conscious layer of thought. And while Smith’s case showed the incredible potential for helping paralyzed patients, it also opened a Pandora’s box of privacy concerns.
Here’s why this matters to you, even if you’ll never have a brain implant:
The technology isn’t staying in medical labs. Consumer BCIs are already on the market. Headbands that claim to improve focus. Gaming devices that read your brain waves. Meditation apps that monitor your mental state.
And right now, there are virtually no laws protecting what companies can do with your neural data.
If you’re concerned about protecting your digital privacy in this new era, resources like The Art of Invisibility: The World’s Most Famous Hacker Teaches You How to Be Safe in the Age of Big Brother can help you understand the broader landscape of data privacy and how to protect yourself.
Your Brain Data Is Already Being Sold
Here’s something that should alarm everyone: A 2024 analysis of 30 consumer neurotech companies by the Neurorights Foundation showed that nearly all had complete control over the data users provided. That means most firms can use the information as they please, including selling it.
Let that sink in. Companies are collecting brain data from consumers and have the legal right to sell it to third parties.
In April 2025, Democratic Senators Chuck Schumer, Maria Cantwell, and Ed Markey called for an investigation into neurotech companies’ handling of user data, warning that neural information is being collected and potentially sold without clear consent.
Unlike your browsing history or purchase records, neural data can reveal:
- Your mental health conditions
- Emotional states in real-time
- Cognitive patterns and decision-making processes
- Pre-conscious intentions you’re not even aware of
- Potential future behaviors
Studies have shown that such data may be used to infer visual content of mental processing, covert speech, or even reportedly to predict future tendency of carrying out certain acts.
The privacy implications are staggering. This isn’t just about targeted ads. We’re talking about technology that could potentially predict what you’re going to think before you think it.
The “Read Your Mind” Devices Are Already Here
You might assume these concerns are theoretical, something to worry about in the distant future. But the future is now.
Elon Musk’s neurotech firm Neuralink has surgically implanted its device in the motor cortices of at least 13 volunteers who are using it to play computer games and control robotic hands. More than 10,000 people have reportedly joined waiting lists for clinical trials.
And it’s not just Neuralink. At least five more BCI companies have tested their devices in humans for the first time over the past two years.
The medical benefits are undeniable. These devices are giving paralyzed people the ability to communicate, control prosthetics, and regain independence. That’s genuinely life-changing.
But here’s the uncomfortable truth: Once this technology moves beyond medical use into consumer applications, the privacy protections become murky at best, and nonexistent at worst.
Consumer BCIs currently on the market include:
- EEG headbands for meditation and focus training
- Gaming peripherals that respond to brain signals
- Sleep optimization devices that monitor brain waves
- Productivity tools that track attention and mental fatigue
These devices don’t require surgery. They work from outside your skull. And most consumer BCIs don’t use secure data-sharing channels or implement state-of-the-art privacy technologies.
For those looking to better understand the intersection of technology and consciousness, The Brain: The Story of You by neuroscientist David Eagleman offers fascinating insights into how our brains work and why neural privacy matters.
Why Current Privacy Laws Are Dangerously Inadequate
Most data protection laws, including Europe’s GDPR, weren’t designed with brain-computer interfaces in mind. Without strict regulations, companies or third parties could potentially use, store, or sell your brain data without clear guidelines or accountability.
Only a handful of US states have passed specific neural data protection laws:
Colorado and California (2024) were the first to classify neural data as sensitive personal information. Minnesota went further, creating civil and criminal penalties for violations of neural data rights.
But these laws have significant limitations. Ethicists fear such laws are insufficient because they focus on the raw data and not on the inferences that companies can make by combining neural information with parallel streams of digital data.
Think about that. Even if a law protects your raw brain signals, companies can still combine that data with your:
- Social media activity
- Purchase history
- Location data
- Search queries
- Health records
The resulting profile could reveal aspects of your inner life you’ve never shared with anyone.
According to a report surveying privacy policy of 30 companies, there is enormous ambiguity regarding whether companies consider neural data even as a form of personal data. Furthermore, their data collection and storage practices are unclear, and almost all companies reserve the right to share data with third parties.
The AI Factor Makes Everything More Dangerous
Here’s where things get even more concerning: artificial intelligence is supercharging what BCIs can decode from your brain.
AI algorithms can now:
- Turn noisy brain signals into actionable data
- Detect pre-conscious responses and intentions
- Build “foundation models” trained on thousands of hours of neural data
- Make predictions about your future thoughts and behaviors
- Potentially influence your decision-making processes
AI is deeply intertwined with these advancements, enabling BCIs to detect errors before users are aware of them, or assist with real-time communication.
But this also introduces difficult questions about user agency and consent. When AI helps your BCI work more efficiently, where does your thought end and the machine’s interpretation begin?
Ethicists worry that, left unregulated, these devices could give technology companies access to new and more precise data about people’s internal reactions to online and other content.
Imagine a future where:
- Advertisers know your emotional reaction to products before you consciously process it
- Employers monitor your attention and mental engagement in real-time
- Insurance companies price policies based on neural data predicting future health issues
- Social media platforms optimize content based on pre-conscious responses your conscious mind never registered
This isn’t paranoid speculation. The technology to do all of this either exists now or is in active development.
Understanding how algorithms shape our digital lives has never been more important. Weapons of Math Destruction: How Big Data Increases Inequality and Threatens Democracy by Cathy O’Neil provides crucial context on how data-driven systems can harm individuals and society.
What Researchers Say About “Mind Reading”
Let’s address the big question: Can BCIs actually read your mind?
The answer is nuanced. Current technology cannot decode your complete, detailed thoughts like reading a book. While the potential uses of BCIs are numerous, BCIs cannot at present or in the near future “read a person’s complete thoughts,” serve as an accurate lie detector, or pump information directly into the brain.
But that doesn’t mean the privacy concerns are overblown.
The ability of these devices to access aspects of a person’s innermost life, including preconscious thought, raises the stakes on concerns about how to keep neural data private.
Modern BCIs can detect:
- Intentions to move before conscious awareness
- Emotional states and stress levels
- Attention and cognitive load
- Recognition of familiar faces or objects
- Responses to stimuli you’re not consciously processing
“The surprise was that when we go into the posterior parietal, we can get signals that are mixed together from a large number of areas,” says Andersen. “There’s a wide variety of things that we can decode.”
As technology advances, the line between what can and cannot be “read” from brain signals will continue to shift. What’s impossible today may be routine in five years.
The Slippery Slope No One’s Talking About
Nancy Smith’s experience revealed something profound about the nature of consciousness and decision-making. But it also showed us a troubling trajectory.
If BCIs can detect pre-conscious planning, what else might they access that we’re not consciously aware of?
- Subconscious biases we’d never admit to
- Intrusive thoughts we immediately dismiss
- Fleeting emotional reactions we suppress
- Mental associations we’d prefer to keep private
- Intentions we consider but ultimately reject
Brain-computer interfaces could have access to people’s most private thoughts and emotions. This information would need to be transmitted to another device for processing. The collection of this information by companies such as advertisers would represent a major breach of privacy.
Even more concerning: These datasets could be combined with existing databases such as browsing history on Google to provide third parties with unimaginable context on individuals.
The technology doesn’t just threaten privacy through what it reads. BCIs that can write information to the brain raise concerns about manipulation and loss of autonomy.
Real-World Scenarios That Should Worry You
Let’s make this concrete with scenarios that could happen sooner than you think:
Scenario 1: The Job Interview
You’re wearing a consumer BCI that helps you focus during work. Your employer requires it for “productivity optimization.” During your performance review, your manager has access to data showing every moment your attention wavered, every time you felt frustrated, every pre-conscious hesitation you had before making a decision.
Scenario 2: The Marketplace
You’re shopping online while wearing a BCI-enabled VR headset. The system detects your pre-conscious positive response to a product before you’re even consciously aware you like it. The price dynamically adjusts upward because the algorithm knows you’re more likely to buy.
Scenario 3: The Social Network
A social media platform uses AI to analyze neural data from users’ BCIs. It detects pre-conscious responses to content and uses this to optimize the algorithm. You’re shown content that triggers strong neural responses before conscious evaluation, making it increasingly addictive.
Scenario 4: The Insurance Company
Your health insurance company requires you to wear a consumer BCI as a condition of coverage. Neural data reveals early markers of cognitive decline years before symptoms appear. Your premiums skyrocket, or coverage is denied entirely.
None of these scenarios require implanted devices. They could all happen with consumer BCIs you wear on your head.
What Experts Recommend to Protect Neural Privacy
The conversation around neural rights is gaining momentum. Here’s what leading ethicists and researchers say we need:
Nita Farahany, a prominent ethicist at Duke University, argues that “This is a really important thing to protect because it’s one of our most intimate modes of knowing ourselves and figuring out who we let into our private realm.”
Key protections experts are calling for:
- Specific neural data legislation that goes beyond existing privacy laws
- User control and consent for when BCIs collect data
- Transparency about what neural data companies collect and how they use it
- Prohibition on selling neural data without explicit consent
- Security requirements including encryption and secure data channels
- Right to mental privacy as a fundamental human right
The most frequently cited ethical issues include user safety, justice, privacy and security, and balance of risks and benefits.
Some jurisdictions are starting to act. Chile has added the right to mental privacy to its constitution. The government of Chile and the legislators of four US states have passed laws that give direct recordings of any form of nerve activity protected status.
But protection remains inconsistent and incomplete across most of the world.
For anyone concerned about the erosion of privacy in the digital age, The Age of Surveillance Capitalism by Shoshana Zuboff is essential reading that contextualizes neural privacy within the broader trend of personal data exploitation.
What You Can Do Right Now
While comprehensive neural privacy protections may be years away, you’re not powerless. Here are practical steps you can take:
Be skeptical of consumer BCIs. Just because a headband promises to improve your meditation doesn’t mean the privacy tradeoff is worth it. Read privacy policies carefully.
Ask questions. If a company offers a BCI product, ask:
- What neural data does it collect?
- How long is data stored?
- Who has access to my data?
- Can my data be sold to third parties?
- What security measures protect my neural data?
Support legislation. Contact your representatives and voice support for neural privacy protections. The technology is advancing faster than the law.
Educate yourself. Understanding how BCIs work and their implications helps you make informed decisions. The more people understand this issue, the more pressure there will be for meaningful protections.
Consider the long game. Brain-computer interfaces will likely become more common in coming years. The privacy norms we establish now will shape how this technology develops.
The Future Is Already Here
Nancy Smith’s experience with pre-conscious thought detection wasn’t a one-off experiment. It’s a glimpse of where this technology is headed.
“Whole-brain interfacing is going to be the future,” says Tom Oxley, chief executive of Synchron. He predicts that the desire to treat psychiatric conditions and other brain disorders will lead to more brain regions being explored.
The medical potential is extraordinary. BCIs could help treat depression, anxiety, PTSD, and neurological disorders we currently have few options for. They could restore communication to people who have lost it. They could help us understand the brain in ways we never have before.
But without proper safeguards, this same technology could enable unprecedented invasions of privacy.
Your thoughts are the last truly private frontier. Once that boundary is crossed, there’s no going back.
The question isn’t whether brain-computer interfaces will become mainstream. They will. The question is whether we’ll protect neural privacy before it’s too late, or whether we’ll wake up one day and realize we’ve given away access to our own minds without even knowing it.
Nancy Smith’s piano played itself because her BCI knew what she’d do before she consciously decided to do it. What will technology companies know about you before you know it yourself?
And more importantly: What will they do with that information?
The time to demand neural privacy protections is now. Before we all become test subjects in an experiment we never consented to.
For deeper exploration of consciousness, free will, and the neuroscience behind who we are, Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts by Stanislas Dehaene offers rigorous scientific insight into the very nature of the thoughts BCIs are beginning to access.
The technology is fascinating. The implications are profound. And the choices we make about neural privacy today will echo through generations to come.