Visual cortex

• This is the closest science has yet come to reading someone’s mind.
• As Alexander Huth, the neuroscientist who co-led the research, told the New York Times:
  This isn’t just a language stimulus.
• In the longer term, this could lead to wider public applications such as fitbit-style health monitors for the brain and brain-controlled smartphones.
• On January 29, Elon Musk announced that his Neuralink tech startup had implanted a chip in a human brain for the first time.

Humanity’s greatest mapping challenge

• By fully mapping the structure and function of a healthy human brain, we can determine with great precision what goes awry in diseases of the brain and mind.
• Similar initiatives were launched in Europe in 2013 (the Human Brain Project) and China in 2016 (the China Brain Project).
• This daunting endeavour may still take generations to complete – but the scientific ambition of mapping and reading people’s brains dates back more than two centuries.
• With the world having been circumnavigated many times over, Antarctica discovered and much of the planet charted, humanity was ready for a new (and even more complicated) mapping challenge – the human brain.

• In the 1860s, “locationist” views of how the brain worked made a comeback – though the scientists leading this research were keen to distinguish their theories from phrenology.
• French anatomist Paul Broca discovered a region of the left hemisphere responsible for producing speech – thanks in part to his patient, Louis Victor Leborgne, who at age 30 lost the ability to say anything other than the syllable “tan”.

• This approach depends on the findings of American physiologist John Fulton almost a century ago.
• This stronger pulse of activity was not replicated by other sensory inputs, for example when smelling tobacco or vanilla.

The first clinical trial

• The ultimate goal is wireless, non-invasive devices that help patients communicate and move with precision in the real world.
• In 2004, BrainGate began the first clinical trial using BCIs to enable patients with impaired motor systems (including spinal cord injuries, brainstem infarctions, locked-in syndrome and muscular dystrophy) control a computer cursor with their thoughts.

• The team is working with academics from different backgrounds who have been engaged in projects aimed at tackling societal and scientific challenges.
• Patient MN, a quadriplegic since being stabbed in the neck in 2001, was the trial’s first patient.
• In addition, brain activity was linked to the patient’s prosthetic hand and robotic arm, enabling rudimentary actions including grasping and transporting an object.
• Also in 2017, BrainGate clinical trials reported the first evidence that BCIs could be used to help patients regain movement of their own limbs by bypassing the damaged portion of the spinal cord.

A new era of ‘mind reading’ technology

• But having been primarily envisaged as a tool for diagnostics and monitoring, it is now also a core element of the latest neural communication and prosthetic devices.
• Despite being behaviourally non-responsive and minimally conscious, these patients were able to answer yes-or-no questions just by using their minds.
• Now, a decade on, the HuthLab research at the University of Texas constitutes a paradigmatic shift in the evolution of communication-enabling neuroimaging systems.
• Whereas the brain’s capacity to produce motor intentions is shared across species, the ability to produce and perceive language is uniquely human.

• The disadvantage of fMRI is that it can only take slow measurements of brain signals (typically, one brain volume every two or three seconds).
• They demonstrated that the system could be used not only to decode semantic content entertained through auditive perception, but also through visual perception.
• Importantly, they also explicitly addressed the potential threat to a person’s mental privacy posed by this kind of technology.
• We take very seriously the concerns that it could be used for bad purposes and have worked to avoid that.

The ethical implications are immense

• Losing the ability to communicate is a deep cut to one’s sense of self.
• The ethical implications of providing access to such data to scientific and corporate entities are potentially immense.

• For example, Parkinson’s disease, a neurodegenerative disease that affects movement, is co-morbid with dementia, which affects the ability to reason and think clearly.
• In line with this approach, Chile was the first country that adopted legislation to address the risks inherent to neurotechnology.
• One of the cornerstones of ethical research is the principle of informed consent.
• The growing availability of neurotechnology in a commercial context that is generally subject to far less regulation only amplifies these ethical and legal concerns.
• We are at an early stage of technological development and as we begin to uncover the great potential of BCI, both for therapeutic applications and beyond, the need to consider these ethical questions and their implications for legal action becomes more pressing.

Decoding our neuro future

• By the middle of 2021, the total investment in neurotechnology companies amounted to just over US$33 billion (around £26 million).
• The implant is said to include 1,024 electrodes, yet is only slightly larger than the diameter of a red blood cell.
• The Kernel Flow, for example, is a commercially available, wearable headset that uses fNRIS technology to monitor brain activity.
• The dawn of a new era of brain-computer interfaces should be treated with great care and great respect – in acknowledgement of its immense potential to both help, and harm, our future generations.

For you: more from our Insights series:
Unlocking new clues to how dementia and Alzheimer’s work in the brain – Uncharted Brain podcast series

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Stephanie Sheir received funding from the EPSRC (grant number EP/V026518/1). Timo Istace receives funding from Fonds Wetenschappelijk Onderzoek Vlaanderen. Nicholas J. Kelley does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.