Episode 37 | SCRIPT

TAPP Radio Ep. 37 TRANSCRIPT

The Last Best Story in Teaching Anatomy & Physiology

Episode 37 Transcript

The Last Best Story in Teaching Anatomy & Physiology

Introduction

Kevin Patton: The philosopher, Massimo Pigliucci, once wrote, “Scientific theories are tested every time someone makes an observation or conducts an experiment. So it is misleading to think of science as an edifice built on foundations. Rather, scientific knowledge is more like a web. The difference couldn’t be more crucial. A tall edifice can collapse if the foundations upon which it was built turn out to be shaky, but a web can be torn in several parts without causing the collapse of the whole. The damaged threads can be patiently replaced and reconnected with the rest and the whole web can become stronger and more intricate.”

Aileen: Welcome to The A&P Professor, a few minutes to focus on teaching human anatomy and physiology with host, Kevin Patton.

Kevin Patton: In this episode, there’s more about giving students feedback on their tests, the anatomical compass and learning anatomy, an update in hematopoiesis, and a brief discussion of the idea of the last best story.

Feedback in Online Tests

Kevin Patton: In Episode 36, Adam Rich called in with a question about how I handle feedback to students in my online tests, which I had been describing in previous episodes. He wanted to know whether they got immediate feedback on whether the response was correct or incorrect, and if incorrect, did they get the correct response? My answer said that the students get feedback on which items are correct or incorrect after they’ve submitted their online test. On each incorrect item, it only tells them that it’s incorrect. It does not tell them what the correct answer is, and that’s because I want them to find the correct answer before they take their next attempt. I do give multiple attempts for each of my online tests.

Kevin Patton: What I have them do is try to find it themselves, and if they’re not able to or not confident in the answer they found, I want them to next meet with other students, which I encourage them to do a lot anyway. I want them to get with their study buddies and try to figure it out. If in doing that they are still uncertain about the correct response, before they take the next attempt, I want them to check with me to see what’s going on. I don’t just hand them the correct answer. I walk them through the process of getting to the right answer. So I don’t let them walk away without the correct response, but I don’t just give it to them, so that was the answer.

Kevin Patton: Well, subsequent to that answer going out in Episode 36, a longtime friend of this podcast, Krista Rompolski, mentioned on Twitter that she has 400 A&P students and she has spent many hours reviewing tests with students and that maybe that approach wouldn’t work so well in a very large class. I think Krista makes a very good point saying that. Maybe there are other ways that we can use, like maybe building into the test and the learning management system or whatever we’re using, a way that students can access those correct answers after they’ve gotten them wrong. Maybe it just pops up automatically. I know a lot of instructors that do that and it seems to work very well for them.

Kevin Patton: But even so, I have used the method that I described with as many as 550 students. At one time I was teaching a class of 300 at one school and five classes with a total of almost 250 students at another school. I used the same process for both sets of classes, so I had a lot of students going on too. You know what? It wasn’t too overwhelming. I mean, I do tend to be someone who works a lot, so maybe that’s part of the answer, but it really didn’t seem … Not only was it not overwhelming, it wasn’t even very whelming when you come right down to it. The reason is, is because I really did encourage students to meet with each other and work it out.

Kevin Patton: I also found that when students came to me, either for a few minutes before or after class … And sometimes their schedules didn’t allow that, especially at the school where I was teaching 300. They had things to do right before and right after my class, and so they just … No matter when I would have my office hours, they just weren’t available to come and do that, so both those students and the students at my other campus, some of whom were not so limited, still didn’t often come and talk to me in person. They did when they could and it usually only took a few minutes to kind of walk them through it and sort of lead them along until they found the right answer.

Kevin Patton: I found the more I did that the more I realized it was the same questions or the same kind of questions I got all the time, so I became very well practiced in walking them through that. I could almost right away, just by the look in their eye or the lack of confidence in their step, I could tell them exactly where they were tripping up. I knew where they were tripping up because I had seen it 100 times before, and so I could easily and quickly walk them through it and allow them to see where they had made their mistake. I found that many students, if I did that with them once or twice, I never had to do it with them again because they started to understand the process of how to answer questions and how to find the right answer when they weren’t able to.

Kevin Patton: Another trick that I used … Because a lot of them were answered not in person but by email or through direct messaging through the learning management system. I still to this day keep pages of stock answers to commonly asked questions. Not only for tests but for assignments. Things that students typically get wrong, and instead of writing out a long explanation or a long back and forth questioning each time as original text, I just pull out these pre-composed sections and email that. Then the student might come back with an answer and I’ll have a stock answer of that. Of course, I do modify that depending on the particular situation if I need to, but that way they get a very thorough explanation, a very thorough response without it weight so heavily on me that I’m going to stop responding thoroughly. It’s a win-win situation, and so keeping those cut and paste documents is another little trick.

Kevin Patton: But if any of you have any other ideas on how to handle this if it does start to get overwhelming or what other alternatives there might be that would prevent it from getting overwhelming, especially with a large class like Krista has, then why don’t you call the podcast hotline at 1-833-LION-DEN. L-I-O-N D-E-N. Or email me at podcast@theAPprofessor.org, or reach out to the community on Twitter. That’s @theAPprofessor on Twitter.

The Anatomical Compass

Kevin Patton: When I was a kid, my buddies and I used to love going on hikes, and one of the things that we loved to do was to kind of make our way using maps and compass, and trying to figure out how to use the compass effectively and matching it up to what we were seeing on the map, in comparison to what we were seeing on the ground. As I got older and started doing a lot of traveling, I found that the use of a compass and the ability to read a map is pretty essential to getting around without getting lost, especially if you don’t know the local language very well. When I started studying anatomy, I found that a compass is a useful tool there as well.

Kevin Patton: Now, of course, in anatomy, any compass we use isn’t the same kind we would use in map orienteering where there’s a magnetic north and that matches up with the north that’s on the map. Instead, what I’m talking about is the idea that are, in fact, directions. Just like there are east, west, north, south directions on a map of terrain on the Earth there is a kind of directional compass, an imaginary compass that we can think of when we’re looking at anatomical directions. We have directions like superior/inferior, left/right. Anterior/posterior, lateral/medial, proximal/distal, depending on where we are and the perspective with which we’re looking.

Kevin Patton: Now, I use that anatomical compass idea to identify on diagrams that I use in teaching where the directions are so that when a student is looking at that diagram that I’m using or maybe even drawing on the board they can tell which way is superior, which way is inferior, which way is left, which way is right. How do they know that without really previously being aware of the structure of the human body, or at least not very aware? Well, it’s because I draw them a little compass rosette. A little anatomical rosette.

Kevin Patton: Now, rosette or rose … Rosette just means a little rose. That’s what you see on a regular map. When we were out hiking we would look for the compass rose. It’s usually on the bottom right, but sometimes on other parts of the map. That little compass rosette on the map would have an N on top and a S on the bottom, and depending on how the map was oriented, usually had an E on the right and a W on the left. It was orienting that map to the compass directions of north, south, east, and west.

Kevin Patton: When I draw out, let’s say, a heart on the board and I want to make sure that the remembering which way is the anatomical left and right because that heart is facing them. It’s not facing the same way that their heart is facing, so the student’s left is the heart’s right really. What I do is I just draw a little plus sign with a circle through the middle of it. As soon as I draw that they know because I’ve done it a million times, they know I’ve drawn an anatomical rosette.

Kevin Patton: The next thing they’re going to watch me do is put an S on the top and an I on the bottom so they know that the heart I just drew, the superior aspect is at the top of my diagram, inferior is at the bottom of my diagram, and then on my right and the viewer’s right I put an L to emphasize that as far as the heart is concerned, that’s the left side of that heart that I’m drawing. Then I put an R on the opposite side, and so there is something very visible right away that’s going to remind students and it’s going to stay there so it’s going to keep reminding students that the left ventricle is on the viewer’s right and right ventricle is on the viewer’s left.

Kevin Patton: That may seem very obvious to you and I because we’ve done this a lot. We kind of have made those mistakes and done that, but our students aren’t as well practiced. If I always draw a compass rosette on my diagrams and if I use diagrams from various sources that don’t have that compass rosette, I can add that in there on PowerPoint or whatever medium I’m using. There’s always a way for me to add that in. Some books already have that sort of thing built in so I don’t have to add it in there.

Kevin Patton: Then I go a step further and I ask students to do that. That when they’re drawing sketches in the lab or they’re looking at diagrams in their lab manual or some other resource, I want them to draw in those little compass rosettes. I always tell them, “If there isn’t one that should be the first thing you do is draw that in,” because by drawing that in you have to stop and think, “What perspective do I have here in this photograph or diagram? Which way is left or right or is left or right even relevant in this view? Which way is superior? Which was is inferior? Or is that not relevant in this view or in this section? What is relevant and what should I be putting on my little anatomical compass rosette that I’m making down in the corner?”

Kevin Patton: It’s a tool. It’s a very simple tool, but it’s a tool that students can use to get practice in orienting themselves to which way is up, or which way is down, or maybe I should say which way is superior and which way is inferior? Because it’s not really up and down, is it? It’s superior and inferior. They can adapt that to limbs where distal and proximal might be more important or medial and lateral may be more important than left versus right. They can get practice in making that determination and figuring out, “Well, what are the anatomical directions that are important here?” Simple little tool that you can either suggest to students, especially those students who are having a hard time figuring out which end is up when they’re encountering new diagrams and so on, or you can make it a regular part of your course and maybe even require students to draw them in themselves or give them some practice in doing that.

Sponsored by AAA

Kevin Patton: A searchable transcript and a captioned audiogram of this full episode and its preview episode are funded by AAA, the American Association of Anatomists. Their big conference is coming up as part of the Experimental Biology meeting in April in Orlando, Florida. Find out more at anatomy.org.

Reserve hematopoiesis

Kevin Patton: Well, there’s some news in the world of hematopoiesis. As we know, hematopoiesis is a whole set of processes that occurs in our bone marrow, and especially early in development occurs in other tissue as well. It’s a set of processes in which we are producing new red blood cells and various sorts of white blood cells, and so on. It turns out that there’s evidence that there’s kind of a split system that there are hematopoietic stem cells that are primed to produce different populations of cells, and so we call those primed hematopoietic stem cells.

Kevin Patton: Hematopoietic stem cells, I’m just going to call them HSCs. The new evidence is suggesting that we call those pHSCs. So small P, capital H, capital S, capital C. Primed hematopoietic stem cells. Those are the ones that we’ve always kind of thought about, but it turns out there’s this other division of rHSCs. Those are reserved HSCs. They are hanging in the background and they are the ones that can step up when there is damage to the pHSC system. What kind of things can damage that? Well, there are different kinds of severe stress that can do that, like radiation therapy or accident radiation, for that matter, or chemotherapy.

Kevin Patton: We know that the primed hematopoietic stem cells, they can be damaged, but those reserve cells, they can step up. Apparently, they’re less likely to get damaged, and so they can step up and kick in and help us restore the bone marrow function. Of course, the benefit of knowing about this is that now we can look more closely at how that works and maybe we can find some drug targets or some other therapies that can promote how, and when, and how efficiently that reserve system of hematopoietic stem cells can kick in when we need it to kick in. Little bit of news there in blood cell development. If you want to know more about that, including some diagrams that kind of walk you through some of the details, then take a look at the links in the show notes and the episode page at theAPprofessor.org.

Sponsored by HAPS

Kevin Patton: This podcast is sponsored by HAPS, the Human Anatomy & Physiology Society, promoting excellence in the teaching of human anatomy and physiology for over 30 years. As I mentioned in the preview to this episode, I just registered for both the annual conference in Portland near the end of May and also for the South Regional meeting in Louisville at Bellarmine University at the end of March, and I put in a proposal to do a workshop at each one of those meetings. Are you going to be there too? Hey, the deadlines are coming right up, so go visit HAPS at theAPprofessor.org/haps.

Featured: Last Best Story in Adult Neurogenesis & ANS Pathways

Kevin Patton: Regular listeners to this podcast know that I like to look at the process of teaching human anatomy and physiology as a process of storytelling. We are telling the story of how the body works. We’re telling stories about how the body is put together. When I do that with my students I often use the phrase, last best story. I tell my students, “The stories I’m telling you are the last best story.” What I mean by best stories is the stories that have the most evidence behind them. The ones that are most widely held by those scientists who are experts in that particular area of human science. Of course, it’s the best story in terms of my keeping up with the best stories, and that’s where the last part comes in. The last best story means, well, what is current?

Kevin Patton: We’ve had all kinds of stories over the centuries about different parts of the body, how they’re structured, how they work, and we’ve seen that change as new and better information comes along. That process has not suddenly frozen in modern times. No. That’s the way science works, is that we’re constantly updating our stories. Not only with new data, but sometimes we revisit the old data and reinterpret that older data. Yeah, there are many different ways why we want to revise our stories and what I’m telling you in this course is the last best story, but my students, it’s up to keep up with those stories because this is only the last best story. That’s the best story 20 years from now is likely to be at least a little bit different.

Kevin Patton: I’m bringing that up as sort of the framework for mentioning two stories that are kind of in flux right now. One of those stories has to do with adult neurogenesis in the brain. That is the production of new neurons after birth in humans. In the 21st Century here, this has become a big debate. Just within the last few months, it’s become a big debate because within the last year two big papers came out that seemed to be in opposition to one another. One saying that there is firm evidence of ongoing neurogenesis in the adult human hippocampus. The other one sort of came to the opposite conclusion. There’s a bunch of things that kind of make this harder to figure out than maybe at first glance you think there should be.

Kevin Patton: One of those things is that usually, we compare mammals as sort of as if they’re one thing, and in many ways, we all are one group of organisms as mammals. We look at rodents a lot, right? I mean, rats and mice. We use a lot as models for mammalian biology and more specifically, in our case, human biology. In rodents, you can see adult neurogenesis pretty easily, but in humans, not so much. That’s where it gets a little bit iffy and tricky.

Kevin Patton: In getting to the last best story, a third paper has come out. It’s an article in a journal called Trends In Neurosciences. A neurogenesis researcher by the name of Jason Snyder, he tries to make some sense of what’s going on here and I think he does a good job in helping us clarify what the last best story in terms of neurogenesis in humans is. At least in terms of when it happens in humans. He points out that the evidence we have so far says that human neurogenesis peaks much earlier in our lifespan in terms relative to when we’re born than it would for rats, and mice, and other rodents, and even compared to some of the other primates.

Kevin Patton: Even though it peaks before we’re born, it does continue after birth and it gets lower and lower and lower and lower as we go further and further down the lifespan. But even a little bit of neurogenesis after birth ads up over time, so even though it seems like a tiny amount today and then tomorrow, whatever we have going on is a tiny amount, it does add up. It’s a little more significant even though it’s a small amount. It’s more significant than it first appears. But he also points out that when a mouse pup or rat pup is born they’re in a much different stage of development generally, but also in terms of their nervous development, than we are as humans when we’re born. In other words, we’re a little bit further along that line than rats are.

Kevin Patton: Yeah, when we look at mice and rats, after birth they’re going to have quite a bit of neurogenesis going, and so that’s why it’s so easy to see. When we look at humans, it’s harder to find because we’re not doing very much of it. The other thing that he points out is that while we’re working out exactly how much is going on when after birth in humans, and it does seem like there is some small amount of that, but even if there’s not it’s still useful to look at when it is happening before birth and perhaps just after birth. Because those neurons that are showing up later in the stages of development, they’re probably more capable of plasticity that is important to forming new memories and doing things like that, which is, of course, important and essential in human brain function.

Kevin Patton: You want to hear the last best story? Go to the link in the show notes or at the episode page and look at that paper from Jason Snyder. That might help you figure out what the last best story is. Not that you want to go into all that detail in your A&P course, but throwing out these ideas that, “Oh, scientists are looking at this right now. Scientists are looking at that right now.” That helps our students understand the nature of science. That the story that they’re learning in your course is a great story and a useful story, but get ready for it to change. Here’s our basic information that you ought to know now, that everybody knows now, but get ready for it to change because that’s the nature of science.

Kevin Patton: The other story I just want to mention briefly is one that came out, oh, probably a good year and half or two years ago. It was published in Science from a very respected lab where they came out and said in the autonomic nervous system we normally distinguish between a sympathetic division and a parasympathetic division. When we look at anatomically where these pathways are located we see that they are connected with the central nervous system in the thoracolumbar region, which would be the sympathetic pathways. Then the parasympathetic pathways, they’re coming from the cranial and sacral regions. That has been sort of a classic way of looking at autonomic structure and function for quite some time. That’s what’s in all our textbooks, right? And has been for a long time.

Kevin Patton: What this lab came out with is the idea that, well, maybe that’s not really the way we always thought it was. Maybe we’re kind of stuck in a rut there and by doing some studies in terms of the gene expression during the embryological development of these pathways they made a case that really a better way to look at the autonomic nervous system would be to simply divide it into cranial and spinal. That all of the spinal pathways we should call sympathetic and all of the cranial pathways then are parasympathetic. That begs the question, what about those sacral pathways? Those pathways that originate in the sacral segments.

Kevin Patton: This group said, “Well, we’re going to call those sympathetic,” because they are when you look at gene expression, when you look at embryological development and so on. They belong with the other spinal pathways, and so this is a way to simplify our understanding of the autonomic nervous system. Well, almost immediately, there was a lot of pushback on that and saying, “Wait, wait, wait a minute. What about the neurotransmitters that are being used?” The original paper’s author said, “Well, yeah, but we’ve always know that there have been exceptions to those rules about the pharmacology that is the neurotransmitters and neurotransmitter receptors that are used along those pathways, so therefore, that really shouldn’t be a question.”

Kevin Patton: They’ve been kind of going back and forth about that. It does look like we’re … The people that really do the science here, that really research in this area are still sticking with the classic model. But I think what’s important to know and what I mention to my classes is that there is this idea out there that maybe things aren’t that way, that maybe there’s a better way or a different way of looking at it. That may help simplify things. It might make them worse, and so if you want to look at the two sides of that debate … I also have a link to a more recent article that just came out not long ago. It kind of looks at both side and looks at the pros and cons of both sides of that argument.

Kevin Patton: You can take a look at that and really dive as deep as you want into the details of how that argument is going, but I think it’s an argument that we ought to be aware of as A&P teachers because it might influence how that story is told as we go forward. But I think more importantly, it gives us a better sense for the kinds of things that happen in human sciences so that when we’re telling our stories in class we can be portraying or telling the stories in a way that is informed by that process and that really … It makes allowances for those changes that can and do occur in the way we tell our stories.

Kevin Patton: There you go. That’s my last best story for this episode.

Aileen: The A&P Professor is hosted by Kevin Patton, professor, blogger, and textbook author in human anatomy and physiology.

Kevin Patton: This podcast is not recommend for use by children under 12.

Last updated: September 20, 2021 at 19:39 pm