Stanford Science Penpals
Nicholas' Answers to your science Questions
Answers to submitted questions will be answered and updated hopefully on a weekly basis. Nicholas will try his hardest to answer in a timely manner. Some responses may answer multiple questions that I grouped together. Check out what other people have asked first! Your burning question might have already been answered! ---Science Penpals
Answered Questions
1. Why does cocaine trigger the brain cell? -Shyloh & Lathan, NM
This video, produced by the National Institute on Drug Abuse, may be helpful as a starting point.
Cocaine alters the activity of brain cells by changing how the brain responds to chemical signals known as “neuromodulators”. Within the brain, small clusters of cells produce neuromodulators such as dopamine, serotonin, and norepinephrine. Although these cells reside primarily in the middle of the brain, they communicate with many other cells throughout the brain by sending out long, wire-like structures known as “axons”. Neuromodulators are released at the ends of these axons, where they traverse a specialized junction between cells called the “synapse”.
The targeted brain cells detect the neuromodulator via specialized proteins known as “receptors”. Once a neuromodulator binds to a receptor, chemical pathways within the cell trigger, which can then alter the cell’s activity patterns.
What happens next? As long as neuromodulators are floating around in the synapse, they can continue to activate receptors on the target cell. Unless you have a way of eventually getting rid of the neuromodulator, the target brain cell will keep getting triggered by the same signal over and over. Brain cells normally deal with this problem in one of two ways: they can either gobble up the neuromodulator to remove it from the synapse in a process known as “reuptake”, or they can destroy the neuromodulator altogether. Cocaine acts by blocking the proteins involved in the reuptake of neuromodulators, leading to higher levels of neuromodulators at synapses.
2. Is it true that LSD or acid kills off a small portion of your brain after every use? -Rhyann, NM
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To my knowledge, there is no strong evidence that recreational doses of LSD kill brain cells. However, drugs do not need to act in such extreme methods to cause long-term changes in the brain. In my research, for example, I showed that brain cells activated by cocaine were more tightly connected to each other a month after a single dose of cocaine. While that is an example of how drugs can affect the physical connections between cells, drugs can also alter the strength of connections between cells. Drugs can lead to other changes in the structure of individual brain cells, and can alter the biochemical pathways within cells.
Sometimes, these long term changes are desirable. For example, when doctors prescribe antidepressants such as selective serotonin reuptake inhibitors (SSRIs), the antidepressant effects are usually not seen right away. Instead, the effects usually take 2-4 weeks to appear. Why might that be?
The immediate effects of SSRIs are to increase the concentration of the neuromodulator serotonin (see “Why does cocaine trigger the brain cell?” for how this works). This alone, however, does not appear to be sufficient to cause an antidepressant effect. One hypothesis for how SSRIs work is that the brain responds to increased serotonin levels by reducing the number of serotonin receptors over the course of days or weeks, slowly changing how brain cells respond to serotonin (see image).
However, drug use can also lead to all sorts of undesirable changes in the brain, including drug dependence and addiction. Teenaged brains are particularly susceptible to the long-term brain changes described above; the National Institute on Drug Abuse describes how “the adolescent brain is often likened to a car with a fully functioning gas pedal (the reward system) but weak brakes (the prefrontal cortex).” This is why it is important to only take the drugs prescribed by your doctor, who can monitor potential negative side effects and change your prescription to best fit your needs.
3. How can a mental illness affect the mind development? -Elias, NM
This is a fascinating question that will get you very different answers depending on who you ask. Neurobiologists tend to treat the brain and the mind as two sides of the same coin; mind development is simply the process of the brain changing over time.
Nobel Prize winner Eric Kandel states that "All mental processes are brain processes, and therefore all disorders of mental functioning are biological diseases… The brain is the organ of the mind. Where else could [mental illness] be if not in the brain?"
In this view, mental illness is physically represented in the brain, and acts alongside every other brain process to affect the process of mind development.
A mind-body dualist, however, would argue that the brain and mind are separable processes, where “mental illness” could impact development of the mind independent of physical changes in the brain. The image above is Descartes' conception of how we perceive the outside world. In his view, our eyes would see an object, that information would be transferred to the brain, and then the brain would somehow pass on this information to the "immaterial spirit", which would be where our conscious mind resides.
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The mind-body dualism debate has a rich history dating back to the philosophers Plato and Aristotle, but scientists tend to find such a distinction unproductive since it separates a phenomenon from the observable, testable physical universe.
Preface: Possession or use of marijuana for any purpose is illegal under federal law, even though some states have decriminalized or legalized its use for medical and/or recreational purposes.
Furthermore, teenaged brains are particularly susceptible to long-term changes caused by drug use (see “Is it true that LSD or acid kills off a small portion of your brain after every use?” for more), which is one reason why states allowing recreational marijuana set a minimum age requirement of 21 years. Medical use of marijuana in minors varies by state and is heavily restricted, and must be administered by an adult caregiver.
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Marijuana will act on your body the same way regardless of whether you're using it recreationally or medicinally; see the video above for a brief description. However, marijuana can act very differently depending on its chemical composition.
The active compounds in marijuana fall into a complex class of molecules called "cannabinoids", and the overall balance of cannabinoids varies widely depending on the strain. The two cannabinoids most people know of are tetrahydrocannabinol (THC) and cannabidiol (CBD).
These two molecules act very differently within the body, so medical marijuana patients will often select strains with specific concentrations of THC and CBD depending on their symptoms. The image to the left (courtesy NIDA, via Scholastic) depicts how THC can act on different brain regions to produce different effects.
According to the National Institute on Drug Abuse (NIDA), THC "can increase appetite and reduce nausea. THC may also decrease pain, inflammation (swelling and redness), and muscle control problems", whereas CBD "may be useful in reducing pain and inflammation, controlling epileptic seizures, and possibly even treating mental illness and addictions." However, few controlled clinical trials have been performed using marijuana and its cannabinoid derivatives, so these claims have been difficult to assess.
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Marijuana use is also associated with a wide range of side effects including (but not limited to) impaired memory, mood changes, impaired body movement, and altered brain development. According to NIDA, the FDA approval process for marijuana itself has been slow because "researchers haven't conducted enough large-scale clinical trials that show that the benefits of the marijuana plant (as opposed to its cannabinoid ingredients) outweigh its risks in patients it's meant to treat." However, significant progress has been made toward the medical application of cannabinoids. Quoting from the National Center for Complementary and Integrative Health:
"The FDA has approved three cannabinoids as drugs. In 2018, the agency approved Epidiolex (cannabidiol or CBD) oral solution for the treatment of seizures associated with two rare, severe forms of epilepsy. This drug is derived from marijuana. The FDA has also approved the synthetic cannabinoids dronabinol and nabilone to treat nausea and vomiting associated with cancer chemotherapy in people who have already taken other medicines to treat these symptoms without good results. Dronabinol is also approved to treat loss of appetite and weight loss in people with AIDS. Dronabinol contains synthetic delta-9-tetrahydrocannabinol (THC), a component of marijuana, and nabilone contains a synthetic substance with a similar chemical structure. In 2016, the FDA approved Syndros, a liquid form of dronabinol."
Even though it might feel slow, especially for patients whose conditions might be improved with new medical advances, scientific progress does happen! Might you, the reader, be interested in joining the next generation of scientists?
4. How does medical marijuana affect your body? -Pierrce
Preface: Possession or use of marijuana for any purpose is illegal under federal law, even though some states have decriminalized or legalized its use for medical and/or recreational purposes.
Furthermore, teenaged brains are particularly susceptible to long-term changes caused by drug use (see “Is it true that LSD or acid kills off a small portion of your brain after every use?” for more), which is one reason why states allowing recreational marijuana set a minimum age requirement of 21 years. Medical use of marijuana in minors varies by state and is heavily restricted, and must be administered by an adult caregiver.
Marijuana will act on your body the same way regardless of whether you're using it recreationally or medicinally; see the video above for a brief description. However, marijuana can act very differently depending on its chemical composition.
The active compounds in marijuana fall into a complex class of molecules called "cannabinoids", and the overall balance of cannabinoids varies widely depending on the strain. The two cannabinoids most people know of are tetrahydrocannabinol (THC) and cannabidiol (CBD).
These two molecules act very differently within the body, so medical marijuana patients will often select strains with specific concentrations of THC and CBD depending on their symptoms. The image to the left (courtesy NIDA, via Scholastic) depicts how THC can act on different brain regions to produce different effects.
According to the National Institute on Drug Abuse (NIDA), THC "can increase appetite and reduce nausea. THC may also decrease pain, inflammation (swelling and redness), and muscle control problems", whereas CBD "may be useful in reducing pain and inflammation, controlling epileptic seizures, and possibly even treating mental illness and addictions." However, few controlled clinical trials have been performed using marijuana and its cannabinoid derivatives, so these claims have been difficult to assess.
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Marijuana use is also associated with a wide range of side effects including (but not limited to) impaired memory, mood changes, impaired body movement, and altered brain development. According to NIDA, the FDA approval process for marijuana itself has been slow because "researchers haven't conducted enough large-scale clinical trials that show that the benefits of the marijuana plant (as opposed to its cannabinoid ingredients) outweigh its risks in patients it's meant to treat." However, significant progress has been made toward the medical application of cannabinoids. Quoting from the National Center for Complementary and Integrative Health:
"The FDA has approved three cannabinoids as drugs. In 2018, the agency approved Epidiolex (cannabidiol or CBD) oral solution for the treatment of seizures associated with two rare, severe forms of epilepsy. This drug is derived from marijuana. The FDA has also approved the synthetic cannabinoids dronabinol and nabilone to treat nausea and vomiting associated with cancer chemotherapy in people who have already taken other medicines to treat these symptoms without good results. Dronabinol is also approved to treat loss of appetite and weight loss in people with AIDS. Dronabinol contains synthetic delta-9-tetrahydrocannabinol (THC), a component of marijuana, and nabilone contains a synthetic substance with a similar chemical structure. In 2016, the FDA approved Syndros, a liquid form of dronabinol."
Even though it might feel slow, especially for patients whose conditions might be improved with new medical advances, scientific progress does happen! Might you, the reader, be interested in joining the next generation of scientists?
5. I'm super interested in neuroscience! What is it like to be a neurobiologist? Do you spend the majority of your time in the lab, or analyzing data? How does one get into the field of neuroscience (on the molecular and cognitive level) as a high school student? -Blythe B, CA
As a neurobiologist, it’s amazing to be able to push the limits of human knowledge and be able to contribute toward the improvement of human health and welfare. I began performing neuroscience research at the end of my freshman year of college, which was before I had any formal neuroscience training (no classes, no labs, just an interest in how the brain works). During the summer, I was able to work in the lab full time, but during the school year, I was only able to spend 10 hours a week or so doing research, so my responsibilities changed while I was taking classes. The amount of time I’ve spent on each type of task has varied pretty dramatically over the course of my training.
As a graduate student, I spent part of my first two years taking classes while rotating between different labs each quarter. The goal of these research rotations is to determine where you’ll be performing your Ph.D. research, and to make sure you find a research topic that you’re passionate about. Once you’ve joined a lab, then you’ll be in the thick of it, interleaving planning, experiments, data analysis, and writing as your schedule allows. You may also have teaching duties, and will have to design your experiments around these time constraints. This varies a lot between people, but in my case, my experiments generally take about 6 weeks to complete, with maybe half of that performing experiments and spending the other half doing data analysis, keeping up with the scientific literature, designing new experiments, and more.
It’s very easy to be excited during the initial planning phases of a project, speculating about how you’ll address specific hypotheses and how your results will impact our understanding of the brain. Sometimes it feels like the progress you’re making is moving along at a glacial pace, especially when you’re in the thick of experiments or data analysis. However, everything starts coming together very quickly once you begin writing manuscripts describing the research you performed, and it is extremely satisfying to behold the final product. Then it’s time to go through the entire cycle again!
The grad student cycle. From PHD Comics, by Jorge Cham.
The stem cell research building at Stanford University.
Regarding getting into neuroscience as a high school student, you can take advantage of formal programs offered by the universities near you. For example, Stanford offers an array of options that will match you with a lab.
As for alternatives, you can directly contact professors to see if they have any interest in taking a high school student. You can usually find their contact info by searching by university and by department. In general, you’ll probably have better luck with more junior faculty (assistant and associate professors), who’re usually more willing to take on young trainees. Please be up front about the amount of time you're willing to commit to research, as that will assist in matching you with the right project.
While I didn’t perform any research as a high school student, what I’ve observed is that the easiest way to get established in a lab is to have some sort of existing connection with neuroscience faculty. This, unfortunately, reeks of privilege; I had no contacts like that as a high schooler, and would have been too self-conscious and anxious to reach out to professors blindly. It’s not that professors are trying to perpetuate some sort of “old boys club”, but rather that it’s easier to take a risk on someone new when they come recommended by someone they already know and trust.
I was able to get my first research experience through a formal program offered by my university, and these sorts of opportunities will become more abundant as you progress in your studies. Don’t despair if you can’t immediately get into a lab; high school research experience is by no means a prerequisite for getting into a good college, or for being able to pursue research in the future. Again, you can find research opportunities here at Stanford for high school students HERE.
6. How does long term Adderall use change your personality? -Dean, CA
Quick preface: If you feel like a prescription drug may be affecting you adversely, please discuss the topic with your doctor.
I had a lot of trouble answering this question; I asked many of my colleagues, including multiple psychiatrists, and even they were hesitant to give concrete responses. I will provide a bit of background for other readers before attempting to tackle this topic directly.
Adderall is a medication frequently prescribed for the treatment of attention deficit hyperactivity disorder (ADHD) and narcolepsy. Adderall consists of a combination of psychostimulants known as amphetamines, and the effects of these amphetamines can vary dramatically depending on the dosage. Medicinal doses of Adderall tend to be small, and are generally well tolerated by patients.
Many studies looking at the long-term effects of Adderall use focus on whether or not the drug is safe to take, and whether Adderall use provides lasting benefit to patients. This literature largely indicates that long term use of Adderall is both safe and effective when prescribed appropriately. There is some lingering concern that Adderall use in children may stunt growth, so measures such as height and general appetite are closely monitored as time progresses. The concern is likely overblown, but many doctors prefer to act with an abundance of caution to make sure nothing goes wrong.
However, very few studies even attempt to address questions regarding “personality”. There are a couple studies indicating that long term Adderall use may cause (mostly beneficial) changes in brain structure, and since we believe that personality originates from the communication between brain cells, such changes could impact personality development.
FreeImages.com/Dima Vishnevetsky
Stuff like height and weight are easy to measure, but traits such as “personality” are hard to quantify, and this added variability means that you need to observe many more patients to see a potential effect. When you combine this with the difficulty of following a large number of people over years or decades, these sorts of studies become particularly difficult to perform.
Many personality changes could be due to the direct effects of the Adderall. For example, many patients report higher self-esteem and confidence. However, these traits are not developing in a vacuum, but are likely due to a patient’s increased ability to focus and perform tasks without interruption. This generally leads to positive reinforcement from others, such as being praised by teachers, family, or co-workers.
Most of us, and especially children, are very eager to please those around us, and such reinforcement can further enhance confidence and self-esteem. Over time, this could dramatically change the trajectory of your personality development. Since these changes are incremental, an outside observer might perceive you quite differently, but your inner view of your personality might not have changed much. Would you perceive these differences as changes to your personality?