Archive for the ‘Career’ Category

#SfN13: Day 1

Today I had the treat of meeting Garrett Smith, a fellow North Carolinian, here from Davidson College in Davidson, NC (less than an hour from where I grew up! and where my sister-in-law currently works as an adjunct assistant biology professor). I planned on visiting his poster when I saw it dealt with medial septum (MS), a brain structure that I'm very interested in, and I was not disappointed.

Garrett was kind enough to guide me through his research: the MS provides excitatory cholinergic and inhibitory GABAergic inputs to the dentate gyrus (DG). In addition, a major input to the DG comes from the ipsilateral entorhinal cortex (EC) through the perforant path. There are also a small number of DG connections from the contralateral EC, but apparently not enough to cause depolarization to threshold in the DG (as measured by population spikes in the DG when the contralateral EC is stimulated).

All this changes when the ipsilateral EC is lesioned. Without the perforant path input, something signals the MS and the contralateral EC to form more synapses with the DG. The added input allows the contralateral EC, when stimulated, to provide inputs resulting in population spikes in the DG.

What Garrett's group found was that stimulating the MS shortly before stimulating the contralateral EC significantly increased the size of the population spike evoked from EC stimulation. This indicates that the MS could be involved in the recovery of learning and memory following an ipsilateral EC lesion in rodents by strengthening the contralateral EC input to the DG. What role exactly this plays in vivo is unknown, though it is compelling, as all these structures are involved in learning and memory.

The mechanism by which the MS achieves this potentiating effect is also unknown, but they plan on investigating it in future studies by studying how the DG responds to cholinergic and GABAergic inputs individually.

It was a good day, and I'm excited for tomorrow!

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Blogging at #SfN13

Good news! Between overeating and enjoying the sunny California weather, I will be writing daily posts from Saturday, November 9th, to Wednesday, November 13, as an official blogger for this year's annual Society for Neuroscience meeting! Specifically, my posts will focus on neural excitability and novel methods and technology development, though I may throw in some other things as well. I look forward to it! So stay tuned...

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Academic Papers as a Learning Method

Probably one of the toughest things I had to do as an undergraduate was learn how to read scholarly journal articles. Unfortunately, for those who are in the sciences, these papers are the primary means for communication of scientific questions and results. They are also an effective way for students to learn concepts and techniques common in their field. Although I claim no mastery of reading academic literature, I have learned a few tips over the last few years that I hope will be of help to any who read this. These tips will probably also apply to the other sciences.

When you want to read an article, I recommend having a pen in had to underline parts you think are especially important or that teach things you want to remember (or be able to refer to in the future). Remove all distractions. I usually listen to music when I work. When I need to read a paper, that's a bad idea. I've also found that reading aloud helps me to focus and think about what I'm reading. You can't expect this to be a speed read. It takes time, focus, and patience to succeed.

Those who, like me, are relatively new to their field, should make an effort to read entire papers. Sometimes it is tempting to just look at the figures. Although this is okay in a pinch, I have found that a single paper can help familiarize me with a lot of information if I take the time to read it from beginning to end. That being said, not all the sections are created equally, so I'll explain what I think is the relative use and importance of each of them.

  1. Start with the title - Sounds obvious, doesn't it? The title, when well written, can tell you a lot about what the paper will--and will not--contain.
  2. Read the abstract - If you're lucky, this little overview of the paper will give you all you need to know about that subject. It will almost certainly help you decide whether or not it is worth your time to keep reading.
  3. Look over the figures - Herein is the story of the paper. The figures represent the findings of the study, and, if they are properly labeled, should contain enough information to allow readers with some familiarity of the field to understand those findings.
  4. Introduction - These sections I have found particularly valuable in helping me become familiar with my field of neuronal dynamics and electrophysiology. The authors usually start with some very general statements and then narrow their focus. Introductions contain a lot of references which can be helpful if you're looking for other, related papers in your field.
  5. Discussion/Conclusions - This is similar to the introduction, except it is aimed at the future, not the past.
  6. Results - The importance of the results depends on who is reading them. As someone trying to understand the background and experiments, the results are not as important to me. As I become more comfortable with why the questions were being asked and how the results were obtained, I suspect I will be more interested in the results themselves.
  7. Methods - This is one of the most difficult parts of the paper to read. It contains a lot of chemical dosages, parameters, techniques. Here is probably where the learning curve is the steepest, and your information learned/minutes reading will be the least.

Anyhow, these are my current opinions regarding reading scientific journal articles. It is a satisfying feeling to make it through a paper and feel like you understood the majority of it. What things have you learned from your experiences reading papers?

My First Day on the Rig

Last Friday I made my first attempt at using one of the primary pieces of lab equipment I will be using in my research. A rig is a setup that includes a microscope, an electrode manipulator, both mounted on a special table. There is also a lot of tubing that feeds oxygen and artificial cerebrospinal fluid (aCSF) to the small dish that the brain slice is in underneath the microscope. The electrode manipulator is used to move the pipette over minuscule distances and place it next to target cells in the brain slice. Here's a picture I found online that looks like it's similar to my rig.

Although I didn't have a brain slice under the microscope, I did learn how to get the aCSF flowing through the system, how to manipulate the electrode, how to find it under the microscope, and how to move it while keeping track of it with the microscope. I didn't even cause too much damage. It was a preliminary, but good, step for someone who is focusing most of their time on school work outside of the lab.