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Posts tagged “neuroscience

Day #282: Review – Transcutaneous spinal cord stimulation of the cervical cord modulates lumbar networks

Experimental Setup and tSCS electrode placement (A) H-reflexes were evoked via stimulation of the tibial nerve and recorded in the soleus muscle during a consistent background contraction of ≈5% peak muscle activity. The left leg was held static in an extended position, and stimulation to evoke the H-reflex was delivered with the left arm at 0°. (B) tSCS was delivered via two 2.5 cm round cathodic electrodes placed midline at C3-4 and C6-7 (cervical) or T11 and L1 (lumbar) spinous processes. Two 5 × 10 cm rectangular anodic electrodes were placed bilaterally over the iliac crests.
Experimental Setup and tSCS electrode placement (A) H-reflexes were evoked via stimulation of the tibial nerve and recorded in the soleus muscle during a consistent background contraction of ≈5% peak muscle activity. The left leg was held static in an extended position, and stimulation to evoke the H-reflex was delivered with the left arm at 0°. (B) tSCS was delivered via two 2.5 cm round cathodic electrodes placed midline at C3-4 and C6-7 (cervical) or T11 and L1 (lumbar) spinous processes. Two 5 × 10 cm rectangular anodic electrodes were placed bilaterally over the iliac crests.

Experimental Setup and tSCS electrode placement (A) H-reflexes were evoked via stimulation of the tibial nerve and recorded in the soleus muscle during a consistent background contraction of ≈5% peak muscle activity. The left leg was held static in an extended position, and stimulation to evoke the H-reflex was delivered with the left arm at 0°. (B) tSCS was delivered via two 2.5 cm round cathodic electrodes placed midline at C3-4 and C6-7 (cervical) or T11 and L1 (lumbar) spinous processes. Two 5 × 10 cm rectangular anodic electrodes were placed bilaterally over the iliac crests.

It’s that time again! My biweekly critical review paper is due for my PI. He gets a copy and so do all of you. This is a particularly interesting study that falls in line with a lot of research that I am doing, so it’s interesting to see how other groups are progressing. Overall I think this is a great study and while it is behind a paywall, I think I summed it up very well. The drawing they did (above) is awesome, especially for a scientific journal where we normally use simple line figures. Anyway, let’s get to it.

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Day #268: Review – Magnetospinography visualizes electrophysiological activity in the cervical spinal cord

Reconstructed currents of MSG from the cervical spondylotic myelopathy subject. There are two different sets of plots, the furthest left shows the electrophysiological recording taken from the epidural space and the other set shows the reconstructed currents using MSG. They agree fairly well.
Reconstructed currents of MSG from the cervical spondylotic myelopathy subject. There are two different sets of plots, the furthest left shows the electrophysiological recording taken from the epidural space and the other set shows the reconstructed currents using MSG. They agree fairly well.

This is the results of the cervical spondylotic myelopathy subject. The left graphs are the ascending spinal cord evoked potentials (this was electrophysiological recordings taken from the epidural space) by stimulation of the lower thoracic cord showing conduction block at the C4/5 disc level. The right graphs are the reconstructed currents at the midline of the cervical spinal canal (red) and 2 cm lateral (blue). The leading component (the first waveform in red) attenuated and disappeared through C4–6, and the trailing component (the second waveform in red) disappeared at C5/6. The perpendicular inflow components greatly attenuated at C4/5 (the second waveform in blue).

Another two weeks, another critical review. This time I was more critical than review, unlike the last one where I was blown away at the possibilities. Why was I more critical with this one? Well in my opinion, the authors took a baby step when they should’ve taken a leap. All that aside, it is an interesting study and one I hope has several follow up experiments. This one is open access as well, so have a read for yourself if you’re interested.

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Day #257: Tomorrow…

Sisyphus

Well we’re up against the wire now. Tomorrow is the due date for my paper and with it the video I am working on. Will I make it? How much work is left to do? Why am I talking in questions? Find out more… now…?

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Day #256: Two days left…

cookie monster

A live shot of me waiting for my data to finish processing

Well here we are and it’s… ♫ the finalllll count dowwwwwn!! ♫ My paper is due sunday at midnight and between the video I need to make, the data that still needs to be processed, and a shitty team mate who has done absolutely nothing to help, well I’ve got my work cut out for me.

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Day #255: The impossibility of complete knowledge

Magic-spells

Have you ever tried to learn something and you just can’t seem to get it to stick in your brain? That would be my life, well most of my adult life since I left the Marines. There is just so much knowledge in the world and wrapping my brain around even a fraction of a fraction of a fraction of that knowledge seems to be an impossible task. So what is one to do?

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Day #254: Review – A Brain to Spine Interface for Transferring Artificial Sensory Information

Fig.1 of paper showing drawing of implanted electrodes and the two experimental setups for the rat.
Fig.1 of paper showing drawing of implanted electrodes and the two experimental setups for the rat.

Experimental setup for artificial sensory discrimination using DCS and brain-to-spine interface. (a) Rats were implanted with recording electrodes in motor cortex (M1), somatosensory cortex (S1) and striatum (STR) and dorsal column stimulating electrodes in the thoracic epidural space.  (b) Behavioral setup for artificial sensory discrimination using DCS (c) Setup for the brain-to-spine interface consisted of two modified aperture width tactile discrimination boxes.

If you ever were to read one of my review papers, this one’s for you. It’s so awesome and falls in line fairly closely to the things I want to accomplish, albeit going a different route to get there. I’m super excited to share this with all of you and I hope I did the study justice in my summation and while I admit, I had far too much enthusiasm with this one, it shouldn’t take away from just how amazing this is, see for yourself! The study is open access too, so if you want to know more details, you can go take a look!

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Day #253: A race to the finish

finish line

Well still quite a bit of work to do and some of it was frustrating, but here we are. So let’s run through what I’ve got left to do before the end of the term (ALREADY?!) and talk about the next few posts since I have somewhat of a plan… for once.

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Day #252: Dead…line

dead...line

Today is the day, my group presentation is due. Is it done? Well… sort of? Okay not quite, but we’re getting there. My group member still sucks, but since I yelled at him (in a professional manner of course), he’s gotten a little better and has been more responsive, so what’s the hold up? What a great question, let me explain.

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Day #251: Deadline tomorrow

deadline

Well the apocalypse can’t stop the gears of education. Tomorrow is our final presentation for the class I am in, so there is work to be done and expectation maximization will come another day. For now let’s give a quick rundown of what I’m working on.

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Day #250: Maximum Likelihood Estimation

probability

If we are going to talk about expectation maximization (now that I’m done complaining for a bit), we are going to have to introduce the idea of maximum likelihood. It’s going to be very easy to introduce, but it is a very powerful tool in estimating the state of something. Of course, it takes understanding a little bit of statistics, but trust me, if I can understand it, so can you.

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Day #249: A stern email later…

angry

Photo of me responding to his email …

I don’t want to jinx it, I really don’t, but I have an update on my group member situation and it isn’t completely awful! I mean, I’m still doing all the work and blah, blah, blah, but I’ve got an interesting story and I hope that things will be better now.

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Day #248: A Virtual Conference

background

Every zoom meeting I try to break my PI and get him to laugh, this was my last attempt, still nothing… my work continues.

This will be my first conference since the pandemic and it will be a virtual one. To be completely honest, it wasn’t until yesterday that I was reminded we had one today. It’s a little bit different from our normal routine and I think that is what is throwing me off.
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Day #247: The Kalman filter – Part 2

Kalman filter estimate

The Kalman filter converges on the optimal state estimate using noisy measurements and a model that we create.

Okay I lied, I think we can do a better job explaining the Kalman filter, more importantly I have a fun little demo I can share with everyone. It’s not mine, but I like it a lot and it will give you a feel for what the kalman filter does. So let’s get started!
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Day #246: The Kalman filter

We have 3-dimensions here even though it is a 2 dimensional problem. the third dimension is time, this way we can see the path over the course of the recorded time. Notice there are no units, becuase in this case we were working with synthetic data so the units were meaningless and I did not include them.
We have 3-dimensions here even though it is a 2 dimensional problem. the third dimension is time, this way we can see the path over the course of the recorded time. Notice there are no units, becuase in this case we were working with synthetic data so the units were meaningless and I did not include them.

This is just one application for the Kalman filter, I estimated a two dimensional position using a random walk model. We have 3-dimensions here even though it is a 2 dimensional problem, the third dimension is time. This way we can see the path over the course of the recorded time. Notice there are no units, becuase in this case we were working with synthetic data so the units were meaningless and I did not include them.

Since we’ve been talking a lot about it, I thought it might be a good idea to formally introduce the Kalman filter. This will be a semi-high level introduction (like my knowing your spinal cord series), but at the end of it you should have a relatively good feel for what a Kalman filter is.
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Day #245: Fine, I’ll do it myself.

Thanos - I'll do it myself

I will not fail this class becuase of a shitty team member. I will not allow it, I’ve put too much effort and time into this class to do poorly at the last minute because my team member can’t be bothered to do the job he agreed to do. I suppose, this was… inevitable

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Day #244: The end of the term!?

end of term

Okay, where the hell did that come from?! It’s almost the end of the school term. WHAT THE HELL!? It feels like we just got started, but my instructor just sent out the final assignment, which is due the last week of school… next week. I’m sort of freaking out right now.

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Day #243: Deadlines approaching!

deadlines

It seems like it’s been non-stop for me left and right. I have experiments to do, papers to write, and classes to work on. With the pandemic I was hoping to get a chance to take a break, but nope it seems like I’m even busier than normal. I HAD thought that I was caught up finally when I finished processing some of the experimental data I had laying around, but nope I was reminded yesterday that I had not one, but two major deadlines coming.

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Day #242: Experimenting in the time of a pandemic

Experiment-blur

Another day forward in our new normal. I’ve left the house exactly once in the last two weeks and while it’s nice not having to commute to school, I do miss living in a world without the constant fear of catching the virus. What day is it? Who knows, it doesn’t matter anymore. I do have some things coming up though, so let’s talk about experimenting in the age of COVID-19.

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Day #239: Review – Burst-modulated waveforms optimize electrical stimuli for charge efficiency and fiber selectivity

Example processed nerve responses during stimulation trials.
Example processed nerve responses during stimulation trials.

Example processed nerve responses during stimulation trials. The individual CNAP responses for each stimulus (thin traces) were averaged (thick trace, n=20 stimuli). All traces are shown from time 0 to 6ms. The top trace corresponds to an amplitude of 0, the bottom 1mA, and the traces in between are arranged in increments of 0.2mA. Peak latencies and heights (o’s) and widths at half peak height (x’s) were extracted from the averaged signal. The peaks labeled for the 0mA trial are due to noise and baseline activity. These peaks are not actual response peaks from the nerve and are ignored.

Another two weeks, another critical review and as always since my PI gets a copy, so do you. Technically this should’ve come yesterday, but I really wanted to follow up with the Roosevelt mess going on. In any case today we are looking at something not quite spinal cord stimulation, but has applications in the spinal cord stimulation field. Let’s take a look!

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Day #236: Ugh, coder’s block

coder's block

Okay, maybe not just coder’s block, but I feel like I’ve hit a wall. Every homework assignment I’m given for this class includes a “create your own problem and solve it,” element and for the first two assignments I feel like the topic sort of found me. We can talk about what those two projects were, but let’s first talk about this latest assignment.

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Day #225: Class presentations

Presentation

Presentation

For the past week we have been utilizing online resources so that classes can continue while we are all social distancing. While this is means that we mostly use Zoom, we also have message boards and other resources that we can use. However, these resources are sometimes a poor substitute for in person classes. This is especially apparent when we have certain assignments for the class, such as a group presentation.

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Day #224: Review – Cortical and Subcortical Effects of Transcutaneous Spinal Cord Stimulation

Figure 1 of the paper showing the experimental set-up and the type of pulse used for stimulation
Figure 1 of the paper showing the experimental set-up and the type of pulse used for stimulation

Experimental set-up. (A) Participants were comfortably seated in a customized chair during transcutaneous electrical spinal stimulation (TESS) or sham-TESS for 20 min. TESS was delivered using a surface electrode on the back of the neck between C5–C6 spinous processes segments (cathode) and a surface electrode in each anterior crest of the hip bone (anode) using a custom made 5 channel stimulator (BioStim5, Cozyma). Electrophysiological and behavioral outcomes were tested before (Pre) and immediately after, 15, 30, 45, 60 and 75 min after the end of the stimulation or sham stimulation period. (B) Schematic representation of the type of current used during TESS. We used 5 biphasic pulses at 5kHz with each biphasic pulse lasting for 200us. The middle scheme shows the blocks of 5 biphasic pulses passed at a 30Hz frequency. Lower part of the schematic shows the number of pulses delivered in one second.

Well it’s been two weeks since the last critical review so it’s that time again. As usual, my PI gets a copy and so do all of you. Since I’ve done several of these now (this is number six) I have a category just for these reviews called critical reviews. This is a really new study which tries to help tease apart what we are actually stimulating when we apply transcutaneous spinal stimulation. I think it’s a super interesting paper and I hope you do as well.

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Day #214: Know your spinal cord – The Recap

motor neuron histology

It’s day fifty-four and we’ve hit the end of our journey for this mini-series. For one last time, you can find all our posts in the neuroanatomy category. Everything comes to an end eventually and today I think we should do a small wrap up. This isn’t just a repeat of everything we went over though, we’re going to attempt to tie a lot of the topics together. So let’s give this a shot.

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Day #213: Know your spinal cord – Translating neural signals

whole brain and spinal cord dissected

whole brain and spinal cord dissected

Here we are on day fifty-three, we are nearing the end for sure. I was going to end the series today, but there is at least one more thing that I think will be interesting to cover. As always, you can find all of our posts in the neuroanatomy category, after all there are quite a few now. Today we are going to talk about how the brain and muscles use different signals to communicate. Basically, they speak different languages; let’s talk about what that means.

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Day #211: Know your spinal cord – Transcutaneous spinal direct current stimulation

tsDSC simulation
tsDSC simulation

E amplitude distribution over the spinal cord and nerve surface. The color scale on the right is normalized with respect to the maximum of E amplitude in the spinal cord.

Well after our short break yesterday with my biweekly review paper, it’s back to the know your spinal cord series and we’re on day fifty-two! If you’re here for the first time, you can find the posts in this mini-series in the neuroanatomy category. We’ve taken a few twists and turns since we’ve started the series, but we’ve covered way more than I originally planned. We’ve covered how transcutaneous spinal cord stimulation is thought to work, that post focused on the type of spinal cord stimulation I’m researching. However, there are other ways to stimulate the cord. Transcutaneous spinal direct current stimulation (tsDCS) is a different way to stimulate and today we will talk about the difference.

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Day #210: Review – Cervical trans-spinal direct current stimulation: a modelling-experimental approach

Cervical trans-spinal direct current stimulation - Fig. 3
Cervical trans-spinal direct current stimulation - Fig. 3

Average magnitude of the E-field and average amplitude of its components in the spinal-WM in all montages along the z axis. Position of spinal segments is marked on the grey vertical bar, electrodes are represented by vertical bars and active connectors are marked with letter “A”. Volume plots of the E-field magnitude in cervico-thoracic spinal-WM, brainstem and cerebellum are represented at the right of the average distribution in each montage, with the corresponding colour scales

I lied! I did know what today was going to be on, it’s the fifth critical review paper. Since my PI gets a copy, so do you! To be honest, I need to create a category for these reviews (Update: I did make a category, Critical reviews), but for now, my first looking at elbow spinal stretch reflexes is here. My second where I review modulating spinal cord excitability with a static magnetic field here. The third where I review modulating the H-reflex while walking in spinal cord injury populations. Lastly, my fourth on Motoneuron excitability during voluntary muscle activity in a spinal cord injury population  can be found here. That said, let’s take a look at my latest review.

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Day #209: Know your spinal cord – Microglia

macrophage eating a bactria
macrophage eating a bactria

We cover this in the post, but it’s so cool I had to use it for the featured image.

It’s day fifty-one of knowing your spinal cord! For those of you who just found us, fear not we have all these posts in reverse chronological order listed in our neuroanatomy category. For everyone else, lately we’ve been talking about glial cells. This came about from the post on glial scarring which made me realize we should probably define glia. There are four types of glial cells found in the spinal cord (that we know of) we’ve covered three of them already and today we are talking about the last kind, the microglia.

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Day #208: Know your spinal cord – Ependymocytes

ependymal cells
ependymal cells

Ependymal cells, which create cerebral spinal fluid (CSF), line the ventricles of the brain and central canal of the spinal cord. These cells are cuboidal to columnar and have cilia and microvilli on their surfaces to circulate and absorb CSF.

We made it to yet another milestone, day fifty in our know your spinal cord series! As usual, you can find each and every one of these posts neatly organized in reverse chronological order using our neuroanatomy category. For the past couple of posts, we’ve introduced the types of glial cells, probably a bit poorly, but they are just so complex we can only really focus on a few of the functions. Needless to say they are very important cells. Today we are talking about the third (of four) types of glial cells found in the spinal cord (and brain), that is the ependymocyte. Let’s take a look.

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Day #207: Know your spinal cord – Astrocytes

upregulated spinal cord astrocytes
upregulated spinal cord astrocytes

SNL induces MCP-1 upregulation in spinal cord astrocytes (A–C)MCP-1 expression in the spinal cord of naïve animals (A) and SNL animals at 3 days (B) and 10 days (C). Scale bar, 200 μm. (D–F) High magnification images of (A–C), indicated in the white boxes of A–C, show the dorsal horn of the ipsilateral spinal cord. Scale bar, 100 μm. (G–I) Double staining shows that MCP-1 is colocalized with GFAP, a marker for astrocytes (G), but not with NeuN, a marker for neurons (H) or OX42, marker for microglia (I). Scale bar, 50 μm. DOI: 10.1523/JNEUROSCI.3623-08.2009

Day forty-nine in the spinal cord series! You can find all the posts in this series in our super useful neuroanatomy category. A couple of posts back we introduced glial scarring, one of the problems we need to overcome to help people with spinal cord injuries. That led to the realization that we needed to introduce the glial cells, so yesterday we covered the oligodendrocytes and today we are talking about the astrocyte. Now that we have some background of how we got here, let’s introduce today’s topic.

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Day #206: Know your spinal cord – Oligodendrocytes

Oligodendrocyte wrapped around axons of several nerves

Oligodendrocyte wrapped around axons of several nerves

We made it to day forty-eight! As always, the neuroanatomy category will help you find each and every post in the spinal cord series. It’s all really good stuff! We mentioned yesterday that this was coming, we’re going to do a quick breakdown of the types of glial cells just to make understanding the glial scarring post easier. Plus it helps to understand the functions of glial cells in general when we talk about things that could go wrong. With that, let’s get into oligodendrocytes!

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Day #205: Know your spinal cord – Glial scarring

Spinal cord regeneration
Spinal cord regeneration

Previously injured nerve fibers (red) are shown regrowing through a dense astrocyte scar (green). UCLA research shows that astrocyte scars actually help support nerve fiber regeneration. You can read more about the study from UCLA here.

Here we are at day forty-seven of spinal cord posts. We are definitely wrapping up our series sad to say, maybe we can get to day fifty, that would be a nice round number to stop at. For those of you who want to read all the other posts, the neuroanatomy category has everything in reverse chronological order and will teach you everything from the medullary pyramids, the cauda equina, and all the stuff in between. Today we are talking about glial scarring and why it’s such a problem a topic I realized we should touch on after talking about the problems with invasive spinal stimulation methods yesterday.

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Day #204: Know your spinal cord – Invasive stimulation techniques

paddle implant

It’s day forty-six in our spinal cord series. While we’re nearing the end (maybe), there are still a few things to cover. First, if you’re new, you can find all of the posts in the neuroanatomy category for when you need a quick spinal cord fix. I’ve been debating about this post for some time, but I figure we might as well cover it since we’re here. Today we are going to talk briefly about invasive spinal stimulation and what the future might hold.

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Day #203: Know your spinal cord – Compound action potentials

Action potential recording
Action potential recording

Image from: Get body smart

Day forty-five of the know your spinal cord series is here! With so many posts, you may be wondering how to find them all. Fear not, we have a super helpful neuroanatomy category for all your spinal cord needs. For the past few posts we’ve looked at some very interesting tools to probe the spinal cord. We’ve seen that there are quite a few ways we can go about it, but more importantly they all tell us something slightly different. Today we are looking at the product of that stimulation, the compound action potential.

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Day #202: Know your spinal cord – Transcutaneous Spinal Stimulation

TSS model

Welcome to day forty-four in the know your spinal cord series! As usual all of our posts are in a super easy to find neuroanatomy category. Now that we’ve covered our into into diagnostic tools to probe the spinal cord, let’s look at some of the ways we are working to help treat spinal cord injuries. Today we’re looking at a heavy hitter so to speak and something my research is focused on, transcutaneous spinal stimulation (TSS). Let’s take a look!

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Day #201: Know your spinal cord – The V-wave

spine

We’ve made it to day forty-three of our know your spinal cord series! While that is a lot of posts, we’ve made it super simple for you to find all of them with our neuroanatomy category. Lately, we’ve looked at several different tools in our spinal cord probing toolbox. We’ve seen all sorts of different ways to create a response, but we are still missing one important tool for our exploration into the unknown spinal cord world and that is what we are going to talk about today!

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Day #200: Know your spinal cord – Somatosensory evoked potentials

Somatosensory Evoked Potentials
Somatosensory Evoked Potentials

Somatosensory evoked potentials travel from peripheral nerves to the brain and we can record the response along the spinal cord and the brain non-invasively.

We’re back again with day forty-two of spinal cord knowledge series and day 200 in our 365 days of academia series! A friendly reminder that you can find each and every one of these posts in our very helpful neuroanatomy category. Yesterday we looked at motor evoked potentials, or electrical pulses that we create which travel from the brain to the muscles. Today we are looking at the almost reverse, signals we create originating in the peripheral nerves and arriving at the somatosensory cortex of the brain.

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Day #199: Know your spinal cord – Motor evoked potentials

Transcutaneous magnetic stimulation of the brain
Transcutaneous magnetic stimulation of the brain

Transcutaneous magnetic stimulation (left) stimulating a portion of the motor cortex, which travels down the spine and activates a muscle (right)

Day forty-one in the know your spinal cord series. While the number of posts is going up, we made them easy to find by using our awesome neuroanatomy category! Maybe we did this a bit backwards, but it’s our series and this was the order we did it in. Yesterday we covered cervicomedullary motor evoked potentials, which is a subset of what we will be covering today. So again, slightly out of order, but hey let’s look at motor evoked potentials.

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Day #198: Know your spinal cord – Cervicomedullary motor evoked potentials

Brainstem

Brainstem

We made it, day forty in the know your spinal cord series! I honestly didn’t think we would get this far into things, but here we are. As per usual, if you’re new you can find all of the posts in this series in our super helpful neuroanatomy category! For the rest of you, or the ones interested in this topic, today we are looking at yet another tool in uncovering the secrets of the spinal cord.

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Day #197: Know your spinal cord – The F-wave

H-reflex vs F-wave

It’s day thirty-nine of our know your spinal cord series and we’re only touching the surface (so to speak)! If you’re just joining us, then welcome! You can find all of our spinal cord knowledge in the handy neuroanatomy category. Well as these things typically happen, yesterday brought up an interesting gap in our knowledge base. While I introduced the H-reflex, we never talked about the F-wave! So of course yesterday’s post probably left some of you scratching your head as to what an F-wave even is, fear not we’re going to clear that up today!

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Day #196: Review – Changes in Motoneuron Excitability during Voluntary Muscle Activity in Humans with Spinal Cord Injury

Figure 1
Figure 1

Figure 1. Experimental setup. A, Schematic representation of the hand showing the ulnar nerve and F-waves recorded from the first dorsal interosseous (FDI) muscle. B, On the left side, schematic representation of the head showing the electrodes placed at the cervicomedullary junction and on the right side a raw trace showing a cervicomedullary motor evoked potential (CMEP). C, A cartoon showing the concept of the visual feedback. Individuals were tested at rest (left single horizontal line) and during 5% (middle double horizontal lines) and 30% (right double horizontal lines) of maximal voluntary contraction (MVC).

A little detour from our spinal cord series for my fourth critical review paper. As usual, my PI get a copy and so do all of you! You can read my first looking at elbow spinal stretch reflexes here. My second where I review modulating spinal cord excitability with a static magnetic field here. Or the third where I review modulating the H-reflex while walking in spinal cord injury populations. Today is an interesting paper on motoneuron excitability while walking in spinal cord injury populations. It’s a really cool paper, so here’s my review.

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Day #195: Know your spinal cord – The spinotectal tract

Anterolateral-view-of-lumbar-spinal-cord

Welcome to day thirty-eight in the know your spinal cord series. As always, you can find the entire know your spinal cord series exclusively listed under our neuroanatomy category. We’ve amassed quite a bit of spinal information and I’ve gotten into more detail than I originally planned, which is part of the reason why we are going back and covering some of the things we skipped over. Today is one of those topics, we will be talking about the spinotectal tract, not to be confused with the tectospinal tract, which we already covered.

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Day #194: Know your spinal cord – The spinoreticular tract

vertebrae of the spine

vertebrae of the spine

We’ve arrived at day thirty-seven in the spinal cord series and we’re still covering new ground. You can find all of our sweet spinal cord action in the neuroanatomy category, which at this point is pretty extensive for a high-level look. Yesterday we talked about the reticulospinal tracts so today we are talking about the sister tract, the spinoreticular tract. Are they related, or is it all just in the name?

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Day #193: Know your spinal cord – The reticulospinal tracts

reconstruction of the nuclear masses of the brain stem
reconstruction of the nuclear masses of the brain stem

Reconstruction of the nuclear masses of the brain stem

It’s day thirty-six in our spinal cord series and I yesterday I lied, we’re not done quite yet. First, as always we have a super helpful neuroanatomy category for anyone wanting to read the posts from this series. For the rest of us, today we’re talking about the reticulospinal tracts, yes tracts with an s. There is a good reason for this, but you’ll have to read on to see why. (more…)


Day #192: Know your spinal cord – The Tectospinal tract

Cervical spinal cord cross-section

Cervical spinal cord cross-section

Welcome to day thirty-five in the know your spinal cord series! For the new people, we have a whole neuroanatomy category dedicated to these posts! For everyone else (or those of you just interested in today’s topic, this is going to be on another smaller tract of the spinal cord we haven’t covered yet. Today we are talking about the tectospinal tract, not to be confused with the spinotectal tract, so let’s get started.

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Day #191: Know your spinal cord – The Vestibulospinal tract

cranial nerves
cranial nerves

No, we’re not moving away from the spine, but we are talking about the cranial nerves.

It’s day thirty-four in our spinal cord series. As usual, if you’re new here welcome and you can find each and every post in our series in the handy neuroanatomy category! All the posts are in reverse chronological order and while we don’t technically have a specific order, you should probably start with the medullary pyramids and work your way forward. If you’re here, then you probably are interested in the vestibulospinal tract, something we haven’t covered yet, but fear not, we are going to do that now.

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Day #190: Know your spinal cord – The landmarks

human cervical spinal cord cross section
human cervical spinal cord cross section

A human cervical spinal cord slice. Once you’ve read this post, you should be able to identify the major parts and tell which side is the front of the cord.

Welcome to day thirty-three in our series. For those of you who are just finding us, we have every one of these posts in our neuroanatomy category in reverse chronological order. Today we’re going to backtract (get it?) a little and go over something basic, but something we’ve skipped over to this point. We never really talked about the landmarks of a spinal cord slice. So today, we are going to take a detour and go over spinal cord features.

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Day #189: Know your spinal cord – The Ramus

dorsal rami innervation

Today is day thirty-two in our know your spinal cord series. If you’re just joining in, as I usually do in the intro, we have a whole neuroanatomy category just for these posts so you don’t have to dig for them! Today we are covering a couple of structures that fall under the same broad category, ramus. What are they and what do they have to do with the spinal cord? Well that’s what we’re about to find out!

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Day #188: Know your spinal cord – The spinal nerves (revisited)

spinal roots

spinal roots

Here we are at day thirty one of knowing your spinal cord and we’re still going strong. I’m very happy that I cataloged all of these posts in the super handy neuroanatomy category, which should make it easy for you to find each and every one of them! Today we’re talking about something we’ve touched on in the past, but deserves its own post, the spinal nerves. We need to cover this for the next couple of posts, where things get a little… odd. So let’s get started!

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Day #187: Know your spinal cord – The anterior white commissure

Cross section of human spinal cord
Cross section of human spinal cord

Cross section through human spinal cord (lumbar region, L1) showing motor neurons. Astrocytes and oligodendrocytes are labeled ‘A’ and ‘O’, respectively. The objective magnification used is 40x.

Welcome to day thirty of knowing your spinal cord. I feel like that is a lot of spinal cord knowledge for just covering the basics. In any case, if you’re just finding us, welcome! I’ve created a whole new neuroanatomy category just for these posts so you can find them easy and they are in reverse chronological order. Is the anterior white commissure a tract of the spinal cord? Well not really, but it does have an important job and we keep referencing it, so let’s talk about what it does exactly.

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Day #186: Know your spinal cord – The spino-olivary tract

Spinal cord slice
Spinal cord slice

Spinal cord anatomy

Day twenty-nine, wow does time fly! We have over four weeks worth of fun spinal knowledge for you to tap into, all in reverse chronological order in our handy neuroanatomy category! If you read the title, you know we’re back on tract (see what I did there?). Today we’re talking the spino-olivary tract, or is it the olivospinal tract? Keep reading to find out!

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