It has been an excellent year for neurotech, if you ignore the people funding it. In August, a tiny brain implant successfully decoded the inner speech of paralysis patients. In October, an eye restored sight to patients who had lost their vision.

It would just be better, say experts, if the most famous investors in the space – tech magnates such as Elon Musk and OpenAI’s Sam Altman – were less interested in uploading their brains to computers or merging with AI.

“It’s distorting the debate a lot,” said Marcello Ienca, a professor of neuroethics at the Technical University of Munich. “There is this long-term concern regarding the narratives they use.”

Michael Hendricks, a professor of neurobiology at McGill, said: “Rich people who are fascinated with these dumb transhumanist ideas” are muddying public understanding of the potential of neurotechnology. “Neuralink is doing legitimate technology development for neuroscience, and then Elon Musk comes along and starts talking about telepathy and stuff.”

Silicon Valley firms have ramped up investment in neurotechnologies in the past years, with Altman in August co-founding Merge Labs, a competitor to Musk’s Neuralink. Apple and Meta are both working on wearable devices that leverage neural data: a wristband for Meta, EEG headphones for Apple.

At this point, said Ienca, most of the US’s big tech companies have dedicated research on neurotechnology: Google’s neural mapping project, for example, or Meta’s acquisition of Ctrl Labs. “The neurotech game is really in the process of going mainstream,” he said.

These technologies have considerable near-term potential to treat a variety of neurological issues – from ALS to Parkinson’s to paralysis. The problem is, their investors don’t always appear to have curing disease as an end goal.

Musk has said brain-computer interfaces like Neuralink’s may one day allow people to “upload [their] memories” and “download them into a new body or a robot body”. Altman, though quieter on the subject, has blogged about the impending “merge” between humans and machines – which he suggested would either through genetic engineering or plugging “an electrode into the brain”. (In 2018, Altman invested in a “100% fatal” brain-uploading startup, paying $10,000 to join its waiting list.)

To be clear, technologies like brain uploading are a long way off, Hendricks and Ienca said: in fact, they’re probably impossible, at least in the foreseeable future. “Biological systems are not like computers,” Hendricks said.

Some worry, however, that far-fetched narratives could stymie actual health advances – for example, by pushing regulators to adopt broad, fear-driven laws.

Elon Musk has said people may one day ‘upload [their] memories’ and then ‘download them into a new body or a robot body’. Photograph: Gonzalo Fuentes/Reuters

Kristen Mathews, a lawyer who works on mental privacy issues at the US law firm Cooley, said all this “sci-fi hype could trigger regulation that would hinder advances in technology that would otherwise have the potential to really help people who need help”.

“It’s completely unrealistic, and it’s hiding the real questions,” said Hervé Chneiweiss, a neuroscientist who chaired a panel of experts advising Unesco on its global standards for neurotechnology, adopted on Wednesday.

The actual frontier of neurotechnology is best understood as encompassing three distinct categories. There are medical devices, such as the brain implants that decode speech, or Neuralink’s electronic chip that allowed a man with a spinal injury to control a computer. There are consumer wearables, a newer frontier that includes devices such as EEG earbuds or, more loosely, glasses such as Apple’s VisionPro that track your eye movements.

Then there are the science-fiction efforts, such as Nectome, the brain-uploading startup, or Kernel, which aims to link brains to computers, or Neuralink’s recent efforts to trademark the name Telepathy.

The first category promises the most powerful advances: restoring vision and hearing, and treating neurodegenerative diseases or perhaps psychiatric disorders. But these devices are extremely tightly regulated – as are all medical devices – and far less advanced than more hype-driven reporting sometimes suggests. A recent paper in Frontier in Human Neuroscience decried the “misleading propaganda” around brain-computer interfaces, saying the technology was still in its infancy.

The second category, consumer wearables, are a thornier regulatory problem. While there has been a spate of reporting on privacy-invasive brain-measuring devices – for example, China’s much-discussed EEG helmets that supposedly monitor construction workers for fatigue, or pupils for focus – it’s far less clear that these have ever worked, or pose a real surveillance risk.

“The evidential robustness of the systems is very limited. There are very few replicable studies,” said Ienca.

Hendricks says devices such as EEG earphones – which companies like Emotiv, for example, are now marketing – are unlikely to be an effective surveillance tool because the data is too noisy and, like signals from a lie detector, unreliable in individual cases.

Chneiweiss, however, argues that they raise real concerns: “If they are used in the workplace, they could monitor your brain fatigue or things like that, and the data could be used to discriminate.”

The science-fiction applications, meanwhile, often rely on the premise that healthy people would voluntarily get invasive brain implants – to communicate with computers, for example, or move objects with their minds.

This is unlikely. If it happened, and if the technology advanced, it might well raise surveillance concerns. But, Hendricks said, it’s extremely unclear if such surveillance would be significantly more useful than the vast amount of granular data – browser histories and purchase data – that big tech companies already have.

“We have so many ways to influence people through language and simple visual media,” Hendricks said. “I don’t think that [brain implants] would catch up for a long time.”

As for brain uploading, Hendricks said the idea came from people in technology who “think about computers too much”, convincing themselves that the brain is hardware and the self is software that can be run on it – or in a computer, or on a robot.

“If I could really be uploaded to be made immortal in a computer, then I should be happy to just kill myself right now as long as someone tells me, like, oh, you’re living in that metal box over there,” he said. “But I don’t think many people would take that bet. I think instinctively we know that’s bullshit.”