Photo used by permission of Chao
Senior Jacqueline Chao uses the micro-manipulator to find the target cell and poke it using an electrode. After this, Chao said she proceeded to lower the electrode, buzz into the cell, inject a current into it, run the protocol and, finally, record from the cell.

This is the fourth installment of a series on internships, jobs and classes that students are taking this summer.

Senior Jacqueline Chao has been interning with Dr. Michael Wright, a neurophysiologist at Sacramento State University, since the beginning of June. Wright’s primary goal is to understand how nervous systems produce different  behaviors. Chao assists Wright in his experiments with leeches’ nerve cells.

 

Q: Why did you choose this internship?

A: I was figuring out what to do over the summer, so I decided to ask (biology teacher Kellie Whited) if she had any internship opportunities for me.

(Later, Whited) told me that she had a friend at (Sacramento State University) who was doing research on leeches, and she was wondering if I would be interested. I told her I would love to do it, so she arranged a meeting with (Wright).

During the meeting I got to see (Wright’s) lab and learn what what he is trying to answer. Since I’m interested in STEM (science, technology, engineering and math) and especially biology, I felt that it was a great opportunity for me to get some hands-on experience and see if I enjoy working in a lab.

 

Q: Do you need any background knowledge to do this internship? How did you prepare?

A: It would be nice to know something about neuroscience, like how a neuron responds to stimulus. Before we started, (Wright) messaged me for several weeks, teaching me things about the lab. He emailed me a link that contained material about neuroscience, so I learned a little bit about it before I started my internship.

The day before I started he went over all the basics, and throughout (the internship) he made sure I could understand what was going on and summarized what we were going to do before we actually started. That was really helpful.

Plus, I’ve been watching some videos on my own.

 

Photo used by permission of Chao
Senior Jacqueline Chao pulls the electrode by using a machine that heats up the glass and shapes it into a very fine point. Chao later filled the electrode with a solution.

Q: What do you do during your internship?

A: I started off with really basic things, like pulling electrodes and making solutions. Then I started doing micro dissections, where we cut open a leech and take out the ganglion – which contains the leech’s nerve cells – and examine the cells by pinning it under a microscope.

I made some really stupid mistakes doing that. When I was pinning down the ganglions, you have these tiny little pins that are made with pretty soft metal. If you push too hard, you might bend the pins; I bent so many pins, I can’t even tell you how many. It was pretty rough, but I just needed practice.

Other than that, we record data. We are actually not doing this (really seriously). I’ve only actually done this for less than a month, so (Wright’s) not really trying to make me record (a concrete observation) from experiments. He’s just trying to let me focus on the basics of experiments, like trying to find the bigger cells, which are easier to identify.

 

Q: How did you feel on the first day of your internship?

A: I was very overwhelmed. The first day we didn’t really do anything – (Wright) just went over the concepts.

What I didn’t expect was that there was so much physics involved in them. When you think of neurophysiology and neuroscience in general, you don’t typically think of physics. I haven’t taken any physics classes since freshman year, so I went in there, and he was like, “OK, think of a cell wall where the negative charges collect around here, and the positive charges collect on the other side. What does that look like?” I just stared at him and said, ”Um, like a cell membrane? What are you talking about?” Then he explained that it looked like a capacitor, and I was going through my mind, thinking, “What the heck is a capacitor?”

He went on explaining  ion channels and how they restrict the flow of charges, which are (similar to) resistors, and I thought, “Hey, I know about resistors!” Then he asked, “What is Ohm’s law?” I was just like, “Uh, I don’t remember?” Then he said, “OK, how do you calculate resistors in series? In parallel?” And I was like, “Oh, god.”

I felt like he was somewhat disappointed, but we got over it. I guess it was a good review for physics since I’m taking it next year!

 

Q: How did your first dissection of a leech go?

A: On the first day of dissections, I watched him do it a couple of times (before trying to do it myself). He made everything look so easy when it’s actually really hard. You have to be careful with the ganglion, so you have to try not to cut off anything around it. I think I did OK. I did accidentally cut off the nerve chords a couple of times, and (my dissection) wasn’t really a picture-perfect dissection job, but I did it, and I felt so accomplished after.

 

Photo used by permission of Chao
A leech’s ganglion

Q: Have you made any other mistakes during your internship?

A: I’m starting to get the hang of everything now, but I did make some stupid mistakes. One day I was trying to put our electrodes into a container, and I pushed a little bit too hard and broke the tips of all four electrodes. I was like, “Dr. Wright, I might’ve pushed down too hard, and I might’ve broken the electrodes.” He looked and said, “Uhh … yep.” I was like,” Well, crap.”

 

Q: Were there any interesting things in the lab that you’ve never seen before?

A: Yeah. A dissection is pretty straightforward – you put it on a tray and put it under a microscope. (However,) the thing we use to record nerve cells is a bit complicated.

Basically, you have an air table, which is a table with high-pressured air going under it so that it floats. On the table you have a microscope, and you put the ganglion under the microscope. Then, there are tiny robotic arms (next to the microscope), and you can connect a electrode to them, which is a thin piece of glass that has a very fine point and a hole through the middle, so you can poke the cells and inject currents.

(The machine) is connected to an amplifier, which you can use to manipulate a bunch of things, like injecting a current. The amplifier is connected to something that turns the data into a digital form, which will then show on a computer screen (for further analysis).

 

Q: What was your goal for this internship?

A: I guess the goal was for me to learn what goes into a research project and what it is like to work in a lab.

(Wright’s) main objective is to study how neurons conduct rhythmic behavior in a leech;  he is interested in (experimenting with) heart excitatory neurons in leeches, which control the heart tubes in leeches.

—By Ming Zhu