Hello everyone. My name is Pranav Senthilkumar and I am a junior at Mission San Jose High School in Fremont, CA (SFO Bay Area) For my project at the Alameda County Science fair last year, I designed a neuroprosthetic device using the original SpikerBox and the Human Neuroprosthetic kit.
What is a Neuroprosthetic, and how does it relate to my Project?
Many people are currently unable to live their lives to their full potential due to a disability. Neuroprosthetics is a relatively new field which is left mostly unexplored. My goal is to make an impact on the lives of patients who are currently suffering from disabilities. Since I had previously contacted Dr.Gage while assembling a Backyard Brains project, and he was very helpful, I sent Dr. Gage another email. When I checked my email the next morning, Dr. Timothy Marzullo, cofounder of BYB, had read my suggestion, and directed me to some existing BYB experiments which I could use as a base. (Particularly interesting was the Anuradha Rao Memorial Experiment). After Dr Marzullo helped me refine my idea, I was ready to start.
My plan was to create a successful complete neuroprosthetic for an earthworm. Many prosthetic limbs on the market are simply placeholders for the missing limb, and do not restore full functionality. While prosthetic limbs are definitely superior to having no limb at all, they certainly do not allow the patient to live a normal life. Neuroprosthetics, however, have the potential to add a new dimension to the patient’s mobility, allowing patients to live a normal life. The basic premise of these neuroprosthetic devices is that the brain controls the prosthetic limb, thus allowing the patient to perform tasks that a healthy person can perform. There are millions of research facilities taking use of this incredible opportunity to create the most advanced neuroprosthetic. Originally I planned to use a cricket and an earthworm to test my model as both of these creatures have nervous systems closely related to that of a human. In previous years, I have tested both the neural activity of crickets and the effect of drugs on the heart rate of a daphnia magna, so this year I wanted to use my previous projects as stepping stones to make something impactful. My original intended test subject was the cricket, however that did not provide the desired results (for reasons that I’ll expand on later.) After this unsuccessful attempt, I looked for other possible test species. Eventually when I tested the Angleworm, the neuroprosthetic provided excellent results, and so all future trials were performed on the Angleworm.
My Project:
After reconfiguring the original BYB Neuron SpikerBox with select parts of the Neuroprosthetics kit, I began by testing my new neuroprosthetic device on crickets, since crickets and cockroaches are usually the primary test species for BYB projects. However, after a few trials, it was clear that the cricket simply wasn’t a feasible test species. After realizing that the earthworm could be a potential test species, I began looking for pet stores in my area which carried earthworms. Unfortunately, none of the pet stores in my area carried earthworms, so I had to be content with using the angleworm as a substitute. Since earthworms are proven to have a nervous system quite similar to that of a human, I was very optimistic about this trial. The Angleworms were successful!
To perform the experiment, first place each angleworm in a container, and apply each of the solutions to the container. Check the heart rate immediately after the previous step has been completed (the heart rate can be tested by simply placing the earthworm under a high configuration microscope and counting the number of beats). Next, record the results, and apply each or the solutions to the angleworms. Now, amputate the hind portion of each of the angleworms. Finally, place both parts of the angleworm on the neuroprosthetic device, and if your device is working, you should see the hind portion of the angleworm mimic the movements of the front portion. There is, however, a time delay. This is a measure of the effectivity of the neuroprosthetic. A lower time delay means it is more effective.
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While building the neuroprosthetic device was the most time consuming part of my project, the ultimate goal was to test whether or not different *drugs had an impact on the effectivity of the neuroprosthetic. First of All, I wanted to test whether stimulants or depressants had any major effect on the effectivity of neuroprosthetics as opposed to the “control group” (treated with a normal distilled water solution). After running multiple trials, I came to the following conclusions:
-Stimulants such as Caffeine can have up to a 40% increase in the effectivity of the neuroprosthetics.
-Depressants Such as Acetaminophen Can have up to a 25-33% decrease in effectivity of neuroprosthetic.
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From this study, we can draw the conclusion that treating neuroprosthetic patients with stimulants like caffeine can improve the quality of their lives significantly.
Afterword: Choosing the right test species:
At first, I tested my new neuroprosthetic on a cricket. The results, however, were far from optimal. The neuroprosthetic simply would not function, and the prosthetic limb would be “dead,” without any sign of movement. At first, I thought that there may be something wrong with the device. I finally convinced myself to test other species on the device, and it turned out that the angleworm was the perfect model organism for my system. Furthermore, it was much easier to observe the heart rate of an angleworm. A possible reason for the success of the angleworm is that the nervous system is incredibly simple, while maintaining a remarkable similarity to that of a human.
