Growing human brains and direct brain-computer connections
CAPE TOWN – As part of the 4th Industrial Revolution (4IR) some mind-boggling advances in technology were made possible by bioengineers. In the Business Report of previous weeks we covered the revolutionary world of gene editing and the enhancement of people’s health through 3D bioprinting of organs and skin and the use of micro-needle patches against obesity and subcutaneous fungal infections.
Just as amazing is the technological progress in the field of neuroscience and brain-computer interfaces (BCIs). Growing (or bio-printing) human organs in a laboratory environment is nothing new. But recently scientists at the University of California, San Diego, have grown a mini brain or organoid with neural activity comparable to the brain of a prematurely born infant.
The value of this organoid that functions like a real brain is that it provides scientists the opportunity to study several neurological and psychiatric disorders, such as epilepsy, autism, stroke and schizophrenia.
Complex though and behaviour
The scientists at the University of California used human induced pluripotent stem cells to grow the organoids. Pluripotent stem cells are induced from adult somatic cells such as skin fibroblasts or peripheral blood mononuclear cells. These cells have the ability to produce several different cell types after genetic reprogramming into stem cells. In the case of this study it was grown into cortical neuron cells – the outer layer of neural tissue that surrounds the brain and controls complex thought and behaviour.
What is particularly interesting is that the scientists were able to keep the mini brains functioning after nearly a year. As the mini brains developed, the researchers measured the generated electrical impulses. After two months the researchers measured scattered brain-wave activity of a single frequency as is typical of an immature human brain.
At ten months researchers discovered multiple frequencies. The functioning of the mini brain was now much more normal as is typical of a maturing human brain when new neural connections have been made. This implies that the mini brains developed and established functioning synapses (the connection between neurons) that allow them to communicate and generate thought, sensation and movement.
Defective neuronal circuitry
When studying neurological and psychiatric conditions researchers found that the brain is usually physically undamaged, and that the disease is rather caused by defective neuronal circuitry. The mini brains would allow researchers to study these neural wiring disorders. They could be used to model diseases and test various therapies, as well as replace brain tissue lost or damaged in a stroke, dementia or even a gunshot. In such cases the tissues will have to relearn the brain function.
Cultivating the most sophisticated organ of a human being and the seat of our consciousness, thoughts, behaviour and personality in the laboratory is remarkable. However, Jürgen Knoblich, organoid researcher and interim scientific director of the Institute of Molecular Biotechnology in Austria, believes that the chances that mini brains will reach the complexity of a real human brain soon, is slim.
In the United States, Neuralink, the secretive company of the famous Elon Musk, recently revealed some of their brain-computer interface (BCI) technology. They developed flexible threads that are less damaging to the brain than current BCIs. The threads are only 4 to 6 micrometres in width (1/10th the size of a human hair), but are able of transferring a much higher volume of data than the BCI technology currently in use - 1000 electrodes versus the current 10 electrodes.
The work Neuralink is doing is not totally new and builds on a long history of academic research such as deep brain stimulation, cochlear implants, and neurostimulation for epilepsy. The first person with spinal cord paralysis to receive a brain implant that allowed him to control a computer cursor was Matthew Nagle. In 2006, Nagle played Pong using only his mind after four days of practicing. Other experimental BCIs allowed paralysed humans to move robotic arms with their thoughts, to stimulate memory formation and to treat depression.
Neuralink could not use any of the existing technologies to directly read neural spikes in a minimally invasive way. Current technology relies on a series of stiff needles fired into the brain by an air gun and has only 128 electrode channels. Except that it has much less channels and records less data than the threads from Neuralink, it also presents a problem of long-term functionality and a strong immune response. Since the brain shifts in the skull but the needles of the array do not, it leads to damage. Neuralink’s thin polymer threads implanted by a precise neurosurgical robot promises to solve this problem. The robot implants 6 threads (192 electrodes) per minute while avoiding blood vessels to lessen trauma in the brain.
To process the data gathered from the brain via the polymer threads, Neuralink developed a custom chip that read, clean up and amplify signals from the brain. Currently it only transmits data via a wired USB-C connection, but eventually it will work wirelessly via Bluetooth to “N1 sensors” embedded inside the body. Neuralink plans to implant four of these sensors – three in motor areas and one in the somatosensory area. Initially it will connect wirelessly via Bluetooth to a battery powered external device mounted behind the ear and will be controlled via a smart phone app.
According to Musk, the major contribution of this cutting-edge technology is to understand and treat brain disorders, but ultimately the company wants to achieve a symbiosis with artificial intelligence (AI). Just like the limbic system (our primal needs and wants) works in symbiosis with the cortex (the thinking and planning part of the brain), Neuralink wants to create a tertiary and digital super intelligence layer through the merging with AI through a high-bandwidth BCI. To some extent humans already have such a layer with their smart phones and laptops, but they are notoriously slow in their output of information via voice or their fingers. By connecting the brain directly to a computer humans would be capable of communicating much faster.
The technology is very promising and would provide a high bandwidth brain connection from flexible threads that would allow the activity of many neurons to be recorded. In fact, everything we perceive are neural spikes. It feels very real to us, but they are just impulses from neurons. Accurate recording and stimulation of these spikes would ensure much more precise outcomes than previous BCIs.
The good news is that the implantation operation would not entail major surgery and would not even require anaesthesia. The bad news is that human clinical studies would probably only start in 2020 after approval from the authorities. At the moment Neuralink is still testing the innovation on rats. Furthermore, Neuralink will be in the beginning only for patients with severe needs and clinical trials will start with people who have complete paralysis through C1-C4 spinal injury, allowing them to control phones or computers.
On a more abstract level, Musk wants to mitigate the threat of AI that could threaten the future of human civilisation. Musk has more than once warned about the dangers of AI and signed a petition for regulation of the development of automated killer AI in weapons. Neuralink’s work will ensure that humans do not fall behind and will be able to merge with AI and plug into the Internet. It seems that the singularity is suddenly much nearer!
Professor Louis C H Fourie is a futurist and technology strategist. [email protected]