How does technology intervene in the brain?

From diagnostics
on the human-computer interface

The brain is an irreplaceable, essential organ. Today it is considered the seat of cognition and sensation, speech, control of movement and breathing, and personality. However, its systematic study only began around 170 years ago. At the beginning of functional brain research, which went beyond purely anatomical descriptions, there were cases of people with brain injuries. The early neurologists recognized that such medical case descriptions could provide information about the functions of the brain: Patients showed different symptoms depending on which area of the brain was affected. However, further research only became possible when technologies made it possible to study the brain more closely in intact humans.

Since then, an entire branch of science has developed that deals with understanding the brain and nerve cells in humans and animals: neuroscience. Neurotechnology was and is indispensable for this. This term covers both techniques that are used for research and those that have been developed for diagnostic and therapeutic purposes. In neurology, neurosurgery and psychiatry, where these findings from research benefit patients, technologies such as computer tomography, electroencephalography (EEG), psychopharmaceuticals and functional magnetic resonance imaging (fMRI) have become indispensable. Among neurotechnologies, scientists distinguish between neuroimaging and biomedical applications that interact directly with the brain. The former are often diagnostic methods that have revolutionized the detection of diseases such as cancer, stroke or epilepsy.

The latter intervene in the physiology of the brain – via chemical or physical measures. In addition to pharmacology, electrical stimulation is one of the most effective methods. The realization that electricity plays a role in the transmission of information in nerve cells began with the work of Luigi Galvani in the 18. century and founded the discipline of electrophysiology. With the further development of electrical engineering, knowledge about the transmission of electricity in nerve cells became increasingly precise, and by the middle of the In the 19th century, Julius Bernstein discovered the action potential, which is now regarded as the basis for measuring nerve cell activity. The first medical methods used externally applied electric shocks, such as electroconvulsive therapy, which was developed in 1938 and is still used today. Increasingly precise neurosurgical operations, such as stereotactic surgical procedures, a better understanding of the brain and extensive basic research on laboratory animals then made it possible in the 1970s to develop deep brain stimulation, also known as brain pacemakers, as a therapy for movement disorders such as Parkinson’s disease. Today, 85,000 patients carry such an implant in their brain, which stimulates certain areas of the deeper layers of the organ with light currents and can thus counteract neurological diseases.

The age of neuroprostheses

Over the last 20 years, prostheses have also been developed that can restore functions in the nervous system using such electrical stimulation. The cochlear implant is a particularly well-established method of restoring hearing. Deep brain stimulation is used to treat symptoms of Parkinson’s disease, technologies such as retinal implants are approved medical products and brain-controlled prostheses are already at an advanced stage of development. Although cognitive and affective disorders have previously been treated with psychotropic drugs, so-called electropharmaceuticals are on the rise: depression could also be treated with deep brain stimulation.

In recent years, research into magnetic stimulation methods and interfaces that connect the brain to the computer have also received a major boost. The latter have the potential to give people who can no longer move back their ability to act.

Soon paralyzed
People only thanks to the power of thought

Some of these electrical technologies interfere deeply with nerve structures and require surgical methods. As the seat of many characteristics that define people as self, the organ is particularly sensitive. Manipulation and surgical procedures on the brain are particularly frightening, as they could have far-reaching consequences for the patient’s psyche. It is therefore not surprising that applications directly in the brain have to overcome many ethical hurdles in order to be accepted by patients. Unethical research on humans in the middle of the twentieth century, especially in psychosurgery with the use of lobotomy, brought brain research into disrepute and the skepticism of that time often still lingers. On the other hand, these technologies raise exaggerated hopes of healing and fantasies of the future, which increase the risk of misuse.

Today, researchers are working on making these methods safer, more effective, lighter and more durable. New technologies such as optogenetics, which combines genetics and electrophysiology, are also being added. Brain-machine interfaces are being further developed so that they can adapt therapies to the states of the brain in a feedback loop. We want to accompany and discuss these developments in our events by giving researchers and the public the opportunity to share their concerns and wishes so that past mistakes are not repeated.

Read more:
An article on the history of deep brain stimulation
Here you can find more information about Neuroimplants by author Thomas Stieglitz
This article summarizes the history of brain research
A brief definition of neurotechnology
On this website you will find detailed information on current technologies
A text about the discovery of the action potential

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