VideoPoints

• ••• • •• • ••••• • •
BIOL 4315 & 6315 Neuroscience Mon-Wed 1-2.30 PM - NEUROSCIENCE Lectture 01 Introduction, First Neurosurgeons, and COVID-19 in the CNS
Help Tour
© Distribution of this video is restricted by its owner
Transcript ×
Auto highlight
Font-size
00:00 This morning is progress. This is lecture one. And I want you
00:08 look at this image here and think what you understand about this image and
00:14 thoughts you may conjure up as you're at this image. Will you understand
00:21 you look at this image? I the slide halfway through the course toward
00:30 end of this course and I'll ask the same question Now that you have
00:34 the material for six weeks or eight weeks, 10 weeks. What
00:39 you think about what comes to mind you're looking at the signage? And
00:46 I say right now, it's just really cool looking image. In my
00:51 , I don't have chad gpt so I don't know how cool it
00:56 . Casper dot io but this is image that illustrates several very important scales
01:05 components of the brain. First of , there's this microscopic scale uh cells
01:13 cellular networks, what is illustrated here neurons and this is the so most
01:21 whose neurons here and these cell bodies Selma's. They have processes coming
01:29 Some of these processes are called Hundreds these are called axons. The output
01:35 the cell is an axon. Most the input into the cell is through
01:40 and through the connections onto the Selma is where action potential is generated and
01:48 is being regenerated and propagated from another which may be located a far distance
01:55 and in the brain that could be cm a far distance away or even
02:00 on the water of tens of the that can separate different parts of the
02:06 neuronal networks. So this axon will the action potential. And when the
02:12 potential will arise at the external terminal will cause the release of the
02:18 So electrical activity will cause the electrochemical will convert it into the release of
02:26 neurotransmitter chemical signal. This is pre neuron which releases neurotransmitter and the post
02:34 neuron will receive that neurotransmitter onto its . And the fact that the post
02:41 neuron is going to be dependent on types of the receptors at that post
02:46 neuron expresses. It contains this very area is called the synapse pre synaptic
02:55 post synaptic. This is called the . Um These are synapses that you
03:03 in the cortex in the brain and are neuro muscular junctions and you have
03:10 synapses also in the spinal cord within spinal cord proper and the spinal nerves
03:16 the command will form what we call junctions onto the muscle so that you
03:23 perform all of the muscle tasks that brain is commanding through the spinal cord
03:28 the spinal nerves to perform at the . This is one of my
03:35 Mhm. Now this is microscopic union shows neurons and these neurons come in
03:45 150 different subtypes. It's a variety neurons. It has slightly different functions
03:52 express different ionic channels different receptors. will produce different patterns of action
04:00 Some very fast frequency patterns, continuous intermittent and slow firing patterns. When
04:08 say firing it's not a gun, an action potential because it's a very
04:13 event that happens this electrical change. so there's very fast communication that is
04:20 . And a single neuron can have to 150,000 synapses and a single neuron
04:28 to integrate that information. A lot this information could be 1000 of excitatory
04:35 , 3000 of inhibitory synapses that are . This neuron has to integrate that
04:41 with a matter within a matter of to make a decision to fire or
04:46 to fire. That is the That's what the neurons, if they're
04:51 enough they will produce an action potential response to the inputs and they will
04:57 that information further down the line. they're not excited enough they could be
05:02 . That means their information will be , will be uh minimized locally spatially
05:12 a specific area of the brain, . And neurons can fire up to
05:18 action potentials are second. That's 600 . That's how fast some of these
05:26 are these neurons which is not very shown a flag about glial cells.
05:32 cells also come in several different subparts will discuss. Real cells actually account
05:38 a larger mass of the cellular mass the C. N. S.
05:44 the brain. The glial functions are little bit different. They don't produce
05:48 potentials. Instead they have these slower of communication that are based on
05:55 Their own election potentials are based on fluxus of sodium and potassium radio communication
06:03 based on slow calcium mediated waves and functions are different. If the function
06:09 neuron is to stimulate another neuron to neurotransmitter to synchronize to excite or inhibit
06:15 self. The functions of glia has do with some slower temporal scale such
06:22 control of inflammation um buffering spatial buffering abnormally increased concentrations of neurotransmitters or ions
06:34 of cida cons control of blood brain that we'll learn a little bit about
06:43 . We also so you have major are neurons and glia within neurons you
06:50 excited neurons that will release excited to neurotransmitter. Glutamate, major amino acid
06:56 in the brain can you have inhibitory that will release the major inhibitory neurotransmitter
07:02 the CMS in the brain called Yeah mom you know Viteri Castle yo
07:09 gather this is a micro microscopic view you can see that if you look
07:16 more macroscopic view you see that the is divided into loads of the frontal
07:25 parietal occipital lobe cerebellum brain stem. is will contain the cranial nerves and
07:32 learn about the cranial nerves processing of out of sensor information from face regions
07:39 down into the spinal cord proper and odd in between each vertebra. You
07:44 the spinal nerve pairs, the spinal and the nerves will be subdivided cervical
07:51 , lumber lumberjack and sacred. Now image illustrates the complex connectivity and all
07:59 the interconnections, all of the axle and the fibers between different networks in
08:04 brain. Illustrated in just a few and reality these pictures even more colorful
08:10 more complex, have billions of neurons the brain. One brand with trillions
08:18 connections. You know what this reminds of. There are seven billion people
08:24 this earth with trillions of connections. the complexity of cellular networks,
08:33 interactions, mechanism of action and so . This as complex is trying to
08:38 the whole world and interactions between seven humans on this earth. And it
08:46 not impossible. It is possible. think this is the task for the
08:51 um century to actually understand the function the brain. From a single unit
09:02 neuron all the way to the whole influence of that single neuron onto the
09:10 brain and the central nervous system. I believe that this will be done
09:14 this will potentially be done through noninvasive techniques that we're yet waiting to discover
09:20 maybe some of these UFOs will drop good clues for us how to move
09:27 with civilization. Okay, so think this image, You will know pretty
09:34 all of the things that I've just and more, you will know all
09:39 these things and more. We just about, you know about the stains
09:45 stain different aspects of neurons and so . A little bit about your
09:50 Mark Bear Barry Connors, Michael They're giants and neuroscience and their way
09:57 thinking. Um They studied a lot the electro physiological about chemical, molecular
10:06 . These are all different levels of in neuroscience. You can be buried
10:11 a single molecule or you can study behavior or you can do both or
10:16 can be looking at neuronal networks or can be working in the F.
10:19 . R. I. Facility in hospital looking non invasively activity in the
10:23 brand. So from single molecule to understanding non invasively activity in the brain
10:32 behavior that different molecules cause in the . Uh The scientists also have spent
10:40 lot of their time and life uh describing and understanding the concept of brain
10:49 . The fact that our brains are . The fact that these synapses that
10:55 have between neurons. They can be the existing synapses or potentially ated.
11:05 can be weakened or depressed. That the activity between these two neurons becomes
11:13 . New synopses can be formed or existing synopsis can be pruned and driven
11:22 and as you're learning new material for today and then I'm going to come
11:26 and reinforce it again as you're learning material, you're doing all of
11:33 you're strengthening the existing synopsis because you heard about action potential. Just a
11:39 , you're also building new synopsis because learning about things that you haven't heard
11:46 and you're also producing new ways in these neuronal networks can communicate with each
11:51 so that you can recall that information the task and apply it into whatever
11:58 you want to take with it for future careers. So brains are plastic
12:07 this plasticity, the theme of plasticity be echoed throughout the course. A
12:13 example of plasticity is plasticity is learning ability to learn. We typically don't
12:21 to elementary school or college at 60 old. We start early because when
12:27 learning is happening there is a period we recall critical period of development during
12:34 there is the highest levels of plasticity the brain. That means that your
12:38 can reshape themselves much easier. Your can recover from injury much easier,
12:46 as if you have a traumatic brain in a child and there's a physical
12:51 in the brain, there might be potential of full recovery depending on the
12:56 of the injury, the duration on aspects involved. But if there is
13:01 loss of neurons and actual injury in brains, they may not be as
13:07 of a recovery or even recovery of functions at all. Another good example
13:15 language, learning foreign language. If come a lot of us are
13:21 come to this country, first three years old, five years
13:26 even if you were in a household english language was not the main
13:30 you're probably indistinguishable from other locals, are surrounding area that you may be
13:40 . But if you came here after years old and there's a reason why
13:44 pick up a second language in kindergarten then fifth grade and then college is
13:49 last chance almost to to learn a language after that. You're very unlikely
13:54 do that because it takes much more and effort to learn that second language
14:01 it as compared to if you were uh, in your early developmental
14:07 And that is because of the plasticity more plastic brains and more malleable brains
14:13 we're younger into early adulthood. And the connectivity gets kind of a set
14:19 its own ways and the synopsis and course there's still plasticity even in adults
14:26 in aging individuals, but it is as robust and the recovery from injuries
14:33 not nearly as as comparable to what happen if there is an injury in
14:38 developing in young brains. So, concept of plasticity. Uh, we
14:44 new synapses and we do things motor , motor skills, we change our
14:50 with evolution. Um, we change brains because we change what our bodies
14:57 doing, We have a map for hands, We have map for our
15:05 in the brain. And so think what we do 30 years ago.
15:15 did not exist? Most of you not around this did not exist.
15:23 means this is not nice. Which a physical shaping of the actual body
15:35 that times the screen time. 10 of what? So if you are
15:43 10 hours stretching and exercising What's going happen to every day you're gonna build
15:49 body great posture, right? You look more, what what happens to
15:55 feel like this for $10. That's happens to it's called the cellphone
16:01 It's affecting actually it's affecting a lot young people. But this is what
16:07 seeing on the outside of the Right? think about if you wanted
16:12 make a phone call 30 years If you want it To write a
16:17 to somebody 30 years ago. What you have to do? I actually
16:21 to take a pen and the paper sit down and compose it. And
16:26 you messed up white it out and messed up really bad. Start over
16:31 that note, write that letter. if you wanted to write like a
16:36 official letter? You want to think typewriter. And on a typewriter you
16:41 two hands. And you were We still do that. You know
16:46 still use all 10 digits when we keyboards. But what do we use
16:52 the phone? Two digits, one or this and this. What
17:00 what are these fingers doing for 10 ? Nothing. They're just staying
17:06 That means that it's not only the but it's also the synapses, the
17:12 and that map that was there for hand to type and to make phone
17:17 is now in the brain is a different map that represents the two dominant
17:22 . They're just clicking away on the . And it's a it's a it's
17:27 problem, you know, guilty as . But I'm also trying to um
17:35 to to to you as a younger that a lot of things didn't
17:40 We shape ourselves around the technologies around that come out. You know,
17:45 used to walk to school and drive school, electric bike now versus a
17:50 bike. There's a lot of things that are changing us. They're changing
17:56 physically, they're changing us mentally They're changing also the connectivity of the
18:04 , which is plastic and lends itself changes. Okay, Okay. Uh
18:11 briefly discuss the roots of neuroscience and first neuroscientists. So about 10,
18:17 ago with people are finding around the are skulls. Well, they date
18:25 10-30,000 years ago explanations of the different that have holes that have multiple
18:32 Early interpretations was there must be there must be battle injuries. But
18:40 there's a closer closer look, you see there's a symmetrical cut in the
18:46 uh in some skulls, there are symmetrical skull. So if you wanted
18:51 injure torture somebody who would not worry having a symmetrical skull cut in the
18:58 . There's also evidence that these uh openings which we call triple nations or
19:05 interpretations that those skull openings, we're not only in multiple locations on the
19:11 but sometimes reopened multiple times. So is happening in parker indian cultures present
19:20 Peru Mesopotamia, present day Egypt. scouts are discovered everywhere throughout. And
19:28 now the interpretation, well this is really injury case, this is something
19:34 . So this is shamanism of some . Again, if it was
19:41 you wouldn't care about the precise incisions the skull and the skull bone.
19:47 so, Okay, well if it's then why do you torture people because
19:54 know, they were prehistoric times and what people did to each other.
19:58 not true either. You know, you if you look back in the
20:03 and you needed help 2000 years 3000 years ago, there was no
20:11 and ambulance and emergency room um you to go to typically an obscure place
20:21 the woods. We're shaman or medicine , that was somewhat of the
20:26 but also where relied upon when somebody sick people would seek them out and
20:32 if they have any special herbs to them to help them. So those
20:37 and those medicine men were at the , the only health care practitioners that
20:44 available. Okay. And really good were actually kept in the in the
20:51 with the emperors and kings and queens and such and cons. So now
20:59 is a tool that's been discovered and tool is a tool by which the
21:06 transformations were made. And this the top of that tool depicts an
21:11 holding another individual, the third one him and making this brain tra pronation
21:20 . So hopefully there's maybe some sort a light form of anesthesia given maybe
21:25 herbal anesthesia. But this is the again. Why would you want to
21:29 something like this? So then it interpreted, It's a spiritual thing,
21:34 person who is obsessed with evil spirits make a hole and evil spirits go
21:39 up because that's what people spirits You know, spirits in general just
21:42 up and never go down. That the interpretation. And and then we'll
21:49 well, okay, so later we that these are potentially the first neurosurgeons
21:56 existed on this earth. Because if have a rupture of the blood vessel
22:02 hemorrhage in the still of the blood the brain coagulation build up. Uh
22:08 blood, it will impact the brain will cause pain, will cause pressure
22:13 start killing neurons and can kill you . How do you clean up a
22:19 a wound like this? The only you have to open up the skull
22:24 you have to clean it out and if it's still accumulating there, you'll
22:28 to open it a little bit maybe three months later and clean it
22:32 , repeat the procedure. What happens you have abnormal fluid build up not
22:37 the blood coagulating but not abnormal fluid up like cerebrospinal fluid, you have
22:41 drain it. And that's also the way you would do it. And
22:46 these we we recognize these individuals shown on the stool is potentially the original
22:54 that we're trying to alleviate pain or or spirits. They may have been
23:01 . There's some biological things with some things that that people were interpreting at
23:08 time in the world. Okay, the last uh thing that I would
23:17 to discuss with you today very briefly to remind you About COVID 19.
23:24 we're going to continue with the This was just a little bit of
23:28 teaser how it all began. And reason why I want to mention this
23:34 and explain things to you is because of us are still dealing with the
23:39 are just dealt with that some of had virus two or three times.
23:43 of my friends, you know the hands. Uh how does this virus
23:52 into the brain? This is what are interested in. This is neuroscience
23:57 . So of course the virus will the body, will affect the
24:02 will cause lack of oxygen in the . But how does that affect the
24:07 ? How does the virus get into brain? But why should you
24:10 You should care. Because if you um, you know, compromise.
24:17 you're vaccinated, you potentially have to a mask. And when the epidemic
24:26 in 2020, there were two types masked wears, the ones that were
24:34 a mask over their mouth only and ones that were a mask over the
24:39 and faith. I mean, and those and uh, I was wondering
24:44 people were doing that. And sometimes would ask them. I said,
24:48 , I can inhale it. It's respiratory, so if I cover my
24:51 , it's okay. Well we forget we're inhaling through our noses too.
24:57 so anything that goes into our you know this, it's also coming
25:04 passages, but everything that's being inhaled our lungs and miles, there's still
25:11 little bit of back flow into our too. So it can, it
25:16 come from outside. Now, the thing about our own noses is the
25:21 anatomy. I don't know why this kind of a disfigured a little
25:25 Let me do it like this. what you have is a unique anatomy
25:37 you have this is the plate right of the skull is referred to as
25:43 reform plate and this is the crew formation which stands for CFP reform formation
25:54 this is called Crystal gallery. And see these little holes in the skull
26:00 . So this is the skull piece here that's sitting basically up in your
26:04 nostrils. It's a little piece of skull that it has physical holes in
26:10 . And through these holes you have receptor nerve endings that descend and dangle
26:18 here in your nasal cavity. And is where older molecules bind. So
26:23 is how you create a sense of or olfaction. And we'll talk about
26:28 fact that the feeling of the south involved secondary order nerves when we talk
26:33 olfaction. But besides the older molecules into this olfactory receptor neurons which create
26:40 of the smells and flavors for You also have the ability for the
26:46 system bacteria to infect all factor at feeling. And in fact olfactory receptor
26:53 . And this is why we lose sense of smell is pretty common chemo
26:58 dysfunction with code that is a loss smell or anosmia because there's infection of
27:04 receptor nerds by the way, if lose the sense of smell, you're
27:11 when you're eating foods, you're left salty, sweet, sour,
27:21 umami spicy, there's no banana, no raspberry, there's no chipotle spicy
27:34 , chipotle a red pepper. doesn't what it is. Salty is
27:39 So all of the flavor perception that create in your everyday life when you
27:46 and when you taste things. Because you consume a food like a banana
27:52 is in your mouth goes back and odor molecules bind to the olfactory receptor
28:00 and the tongue and the taste receptors tell you banana sweet, a little
28:07 tangy. The nose is gonna tell banana. Okay so life becomes pretty
28:16 when you're reduced to that. Some will cause a loss of taste
28:22 With COVID-19 infections is because it can infect the taste receptor neurons. So
28:30 it's really bond. There's no more sweet spicy, there's cold, hot
28:38 soft, hard texture is the only that's left and it can be really
28:47 depressing if you lose it for quite time. I lost my sense of
28:51 for five days and always joke. was one good thing. It was
28:55 I couldn't tell the difference where I if I was in a perfume store
28:59 bathroom. It didn't matter. It all good. But it got really
29:05 of psychologically uh difficult. I don't if any of you have lost sense
29:10 smell but it was like where's my of smell when it started coming back
29:14 was wonderful. I can smell it smells so wonderful except for the
29:22 . So this virus obviously he inhaled virus, it goes into your
29:27 goes into the blood from the If you have high levels of
29:32 a viral load through Vira mia from blood and cross into the brain.
29:40 that's typical. But it can also the nasal cavity. Just inhale your
29:47 breath and it actually can infect your epithelium factor exception. Once the virus
29:57 in the lungs, it compromises levels oxygen and causes slight levels of hypoxia
30:03 brain. And neurons are very sensitive oxygen. So neurons, if they
30:09 oxygen for longer than two minutes they dying. Other organs are not as
30:15 to the loss of oxygen. That's yesterday spoke about Damar Hamlin, the
30:21 player that had a cardiac arrest on field after the hit, he's back
30:26 of the hospital. He doesn't have neurological damage. And the reason why
30:30 because it was a world class medical sitting on the football field sidelines and
30:36 doctor immediately said, I didn't like way he fell and he was administered
30:42 and given oxygen within one or two . And in instances when a person
30:50 like Damar hamlin, he clinically died the football field for however long seconds
30:57 minutes. Uh if a person has cardiac arrest dies or has a cut
31:03 oxygen Uh due to long function for than two minutes, neurons will get
31:10 will get damaged and it could be damage. And people that suffer from
31:15 arrest and died for 5 to 10 , there's typically a decision being made
31:20 you want to revive them back to because the vital organs may be
31:25 But they may be a vegetable for rest of their lives. And that's
31:29 neurons are exquisitely sensitive and they need levels of oxygen supplied through the
31:35 It goes into the blood and crosses the brain and in hypocrisy compromise the
31:42 brain barriers the barrier that protects then that are found in the blood.
31:49 have a lot of substances in the . You haven't ethereal cells that will
31:53 the walls of the blood vessels but substances in the blood if they're really
31:59 , if they're fat soluble, they cross through these cells through the real
32:05 and astro glial cells. So the cells will have their empty, also
32:11 what crosses from the blood into the and everything. Small substances,
32:16 Other bigger substances they may need to transporters, co transporters carriers that will
32:23 they have to bind onto something. so this virus finds to ace two
32:30 and the ace two receptors are found then the real sells its effects on
32:34 cells and infect glial cells and there's variety of glial cells. This is
32:40 astrocytes and we'll have the end feet the blood vessels here. Micro glial
32:45 are legal tender sides. These are subtypes of real cells, if you
32:49 know better as we study the material what happens is that both of these
32:55 , neurons as well as glial cells these two receptors. And once the
33:00 enters into the brain now have multiple uh that it can hang onto and
33:06 very important. So when it comes the olfactory epithelium will study the circuit
33:13 . There is a stew receptors and epithelium which ends up causing the
33:18 The olfactory epithelium ends up causing the in this mucus layer of the olfactory
33:23 , neurons and loss of smell. ace two receptors in general angiotensin converting
33:31 two receptors are found throughout the the brain, heart, kidney,
33:36 , both in the CNS and Um what is their function? Their
33:43 surface receptor that is involved in control blood pressure and hypertension. And so
33:50 learning a lot of things that are to COVID-19 infections have to do with
33:55 blood problems with coagulation of the blood coagulation in the lungs. If the
34:03 is strong in the lungs, coagulated in the brain, if there's infection
34:08 the brain. And so the virus the brain can cause inflammation and can
34:14 cause cell death too. Uh so there's a high viral load that penetrates
34:19 the brain and in the mild cases can cause brain fog and brain
34:26 not just body fatigue but in severe and immuno compromised individuals. It can
34:33 to stroke, it can lead to and cell death of the brain to
34:38 significant loss of function following that. in this lecture that I'm just introducing
34:45 it will come back. I will some new literature and information that is
34:53 emerging on this disease. And the why I want to spend a little
34:57 of time in the sport's first introducing concept and then ending with this concept
35:02 because this is an emergent disease the of it as well as the treatments
35:07 it and it is very much affecting C. N. S. So
35:11 important for us to understand it. as a health issue it's an ongoing
35:16 issue at the moment. Thank you much and I'll see you all next
35:22 on monday. That's a long
-
+