How long will it take before we can read thoughts – 02/21/2024 – Science

On January 29, Elon Musk posted on his social network X, formerly Twitter, about the success of the first surgical intervention to implant a device developed by his startup Neuralink in a human. The name of the device: Telepathy.

In the scientific community, we have been paying attention to the work of Elon Musk’s team since, in September 2023, the FDA (the agency that regulates and inspects food and medicine in the United States) confirmed that the device could be implanted in humans.

Following FDA approval, Neuralink implanted Telephaty in a person chosen from a group of volunteers with quadriplegia and amyotrophic lateral sclerosis.

At first, we can say that the implant was a success. But to know the results it will be necessary to closely follow a study that promises to be long.

What Elon Musk’s team has achieved is very revolutionary from a technological point of view.

Telepathy carries a battery that is recharged externally and has 1,024 electrodes, distributed over 64 wires, which wirelessly transmit measurements of brain activity. The fact that it was approved by the FDA endorses the rigor with which it was produced.

It is expected that Telepathy will be able to measure brain signals related to movement in people with reduced mobility, and that the signals will be used to control the movement of a prosthesis or interact with a computer.

But a muscle signal is in no way equivalent to a thought.

This is what is known as brain-machine interface, but this is not telepathy. Truly revolutionary it would be if the Neuralink device recognized the neuronal activity that thought generates. And this will probably never be achieved.

Dark zone

What is the challenge we face when trying to measure brain signals?

The challenge is the darkness the observer finds himself in after a neuron is activated. This does not happen with other types of cells, such as a heart muscle cell (myocyte).

To measure the electrical activity of a neuron and a myocyte, the same technology is used.

But when a myocyte “fires,” the observer can directly relate the electrical signal to the contraction of the muscle cell. And thus, he understands the effect of contraction, as he observes that the contraction of all myocytes in the heart causes blood to circulate throughout the body.

This does not happen when we observe the firing of a neuron. In this case, the observer does not see any significant change, because the thought generated is not visible: the neuron’s firing is lost in the darkness.

Deep brain stimulators

There are already devices that are implanted in or very close to the brain and that interact with it.

One example is cochlear implants, devices with stimulators located in the cochlea (structure of the inner ear). They are used by people who do not have the cells responsible for transforming the acoustic signals that arrive from outside into the electrical signals that we recognize as sounds.

The implant uses small microphones located in the ear and sends the sounds collected to electrodes spread along the cochlea. Then we are acting very close to the brain, reaching the auditory nerve.

Another device that acts, this time, inside the brain — and which is also duly approved — is the deep brain stimulator. It began to be used to treat Parkinson’s and, later, its use expanded to other pathologies, such as morbid obesity or depression.

Disable neurons without really knowing how they work

With these devices, they act on deep nuclei of the brain. But we still know well how the organ works.

The device used to control motor disorders in Parkinson’s disease (and not to cure the disease), for example, was developed knowing that it was better to render a group of neurons unusable than to leave them as they are.

This device allowed, instead of performing an ablation (that is, burning the cells), the neurons were rendered useless through the constant application of electrical pulses that blocked them. And it is possible to reverse the effect by stopping the device.

However, work to understand in depth the connections between different movement-related nuclei, and discover why a deep brain stimulator works, continues.

And what is there to measure thought?

At this moment we are far from measuring thoughts, intentions, memories or desires. With this type of device, we cannot know what people are thinking.

Even with well-recognized devices, such as deep stimulators, there is no clarity about why they work (not how they work) and what effect they have.

The controversies raised by the implantation of Elon Musk’s chip are understandable. How the brain works intrigues us. It seems that our deepest intimacy is found in the brain and we want to respect it.

We don’t want other people to control us. But for now, that they read our minds or can influence our thinking is not something to worry about.

Will it be possible to relate neuronal activity to our thoughts?

Everything indicates that there will be progress in interaction with machines, but it will not be based on the relationship between neuronal activity and thought. Among other things, because we don’t even have a clear understanding of what it is to think.

Does thought escape physics and it is not possible to measure it?

_{The original article was published on The Conversation and can be read here.}

*Javier Díaz Dorronsoro is professor of Biomedical Instrumentation at the University of Navarra, Spain.