Interview with psychiatrist Amílcar Silva-dos-Santos
Amílcar Silva-dos-Santos is a medical doctor, psychiatrist and a researcher in neurobiology. As a psychiatrist, Mr. Silva-dos-Santos works at the Hospital Vila Franca de Xira, Grupo José de Mello Saúde, Portugal. As a researcher in neurobiology, he works at the Institute of Molecular Medicine in Lisboa, Portugal. From March/2013 to February/2014 he was a visiting scholar at the Neurobiology Department of Duke University, NC, USA. He had the idea of the connection of two spinal cords while working on the project that is now published regarding "A Closed Loop Brain-machine Interface for Epilepsy Control Using Dorsal Column Electrical Stimulation". The idea is to connect two brains of rodents via spinal cord using the electrical signal caused by seizures induced by a drug called PTZ. We have conducted an interview with Mr. Silva-dos-Santos about his work.
Where are your workplaces as a psychiatrist and as a researcher in neurobiology?
As a Psychiatrist, I work at Hospital Vila Franca de Xira that belongs to the Group José de Mello Saúde, in Portugal. As a researcher I work at the Unit of Neuroscience, Institute of Molecular Medicine in Lisbon, Portugal.
When did the idea of connecting two spinal cords hit you? How did you take it off as a project?
From March 2013 to February 2014, I worked as a visiting scholar with my own funds, at Nicolelis lab, in the Department of Neurobiology of Duke University, NC, USA. I went there with the hope of learning brain-machine interface techniques and possibly apply some of them to my field of expertise that is psychiatry. Among other works, I was assigned a PhD project about spinal cord stimulation as a possible therapy for epilepsy. This work is now published and I am a co-author. Basically, the rodents used in the experiments had implants in the brain and also in the spinal cord. It is very hard to learn and master the spinal cord surgery to implant electrodes. Maybe I was lucky because I like surgery and I had previous training in human surgeries. The animals need some weeks of recovery from the spinal cord and brain surgeries. After that, I would perform the experiments to apply the spinal cord stimulation to treat seizures in the rodents. The model of seizures/epilepsy we were using at the time was a pharmacological one with a drug called Pentylenetetrazol (PTZ). The protocol consisted of intraperitoneal injections of the drug (in the abdomen), wait just a few minutes to observe the seizures and then stimulate the spinal cord. However, an electrical noise problem during the stimulation caused some issues and delayed the results for few months. This gave me more time to think about the project. At the time, the pioneer work of brain-to-brain interface was just released. Maybe it was because of the conjugation of this factors that one day in November 2013, while I was performing an experiment, I suddenly, had the idea of connecting the brains of two rodents via theirs spinal cords using the protocol of spinal cord stimulation to treat epilepsy. However, this seemed too much crazy even in that lab. Anyway, I just focused on my project and continued to do the spinal cord stimulation to treat epilepsy until the dawn of 17th of February 2014 (my father´s birthday) when I could not sleep and I had this urge of writing the protocol for the experiments. So, I woke up and wrote the entire protocol including all the steps to built the connection wire. I went to the lab in the morning, I built the wires and I set up the experiments. Using animals with very old implants in the brain and spinal cord that was going to be euthanized, I tried the connection of the two spinal cords and it worked. I repeated the experiment more 2 times in 2 different days. I didn´t tell anyone until the end of February of 2014 because I was planning to gather more data. Unfortunately, I had to come to Portugal in March of 2014, and by the time I told the lab members about these experiments it was too late. I was informed that I could not publish those data. That is why I publish the paper as a hypothesis.
What are the applications in the study of the brain using the electrical signal caused by seizures induced to the brains of the rodents?
This is a very interesting question. I will try to explain it. Some colleagues of mine told me that this protocol is quite unusual, that they would not use it to connect two nervous systems and that they would have used amplifiers. They considered me an outsider. I was trying to be pragmatic. I am a medical doctor and a psychiatrist with some background in neurochemistry and electrophysiology and with thousands of hours of clinical practice that until 2013 had no background in brain-machine interfaces. Traditional works of brain-machine interfaces uses electrical signals that codifies movements such as the classical experiment of the monkey that moves a robot arm with the thoughts or such as the brain-to-brain interface experiments where the code used is a cognitive task performed by an animal (such as to choose a left or right lever or to move a pointer in a 3D space), or brain-spine interface where a motor signal from the brain is sent to the spinal cord of the same animal. Chemical signals transduced to electrical signals (such as PTZ causing seizures) are not traditionally used in these kinds of experiments. There is a notion that I introduced in the paper that I called electrical drug. The electrical signal of a drug can be recorded and injected into the spinal cord for example. If this worked with PTZ and its electrical signal caused seizures, then probably the electrical signature of other drugs must cause the same effects as its chemical effects. However, this is a question that must be studied and confirmed. If it proves to be correct than a new way to study, diagnose and treat neuropsychiatric disorders can be created.
How can applications fit into parts of a spinal cord in a paraplegic/tetraplegic patient?
In my outsider point of view this might be a simple principle. However, it must be studied and tested in animals and in humans. If a complex signal of a sensorimotor information (seizures induced by PTZ) can be sent from the spinal cord from an animal to another, then it might be possible to transfer neural information from the level below a lesion in a paraplegic/tetraplegic patient to the level above the lesion. But, once again, this notion needs to be tested.
What about its potential application to promote relaxation and treat anxiety in the near future?
As I said in my paper, currently, the spinal cord stimulation protocols used are artificial and simple such as the 130 Hz stimulation for chronic pain. There are other stimulation paradigms such 333 Hz in Parkinson´s Disease, 100 or 500 Hz in epilepsy. The PTZ signal used in spinal cord – spinal cord connection can introduce the notion that more complex signals can be injected into the spinal cord and it does not need to come from another animal, of course. It can be recorded in an electrical device and then delivered to the spinal cord. One of such code might be a neural code to promote relaxation for example. This same principle can be applied to other neuropsychiatric disorders.
… In order to continue this work, I will need further support. Hence, I set up a crowd funding campaign to gather some funding to do more work related to the spinal cord – spinal cord connection.
The link to the experiment campaign is:
The paper about the connection of two brains via the spinal cord can be reached here:
A video explaining the paper can be found here:
