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BIOL 6397 Cell Neuroscience Mo Wed 1-2.30pm - CELLULAR NEUROSCIENCE Lecture 01 Neuroscience History and Neurons
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00:02 So this is our first lecture and is the first image. And you
00:06 taken my undergraduate neuroscience course, the that have taken, I told you
00:12 do a little mental exercise for yourselves I will tell everybody here and of
00:17 to do the same thing. Look this image and try to think about
00:21 much you understand what this means to and what this image means to
00:27 And then uh we can look at image again in the middle until we're
00:31 the end of this course and think what it means and what you understand
00:35 that image. But in general N. S. And the brain
00:42 the most important organ and potentially the complex organ and a human body.
00:50 a major controlling organ. It controls brain and it controls the body and
00:57 it you cannot live you have major of the central nervous system which is
01:05 the brain cerebellum, brain stem and cord that comprise central nervous system.
01:13 on a macro level on this gross level you see two hemispheres, the
01:19 and the right hemisphere, you see lobes, the frontal, the
01:26 occipital temporal lobes, sara Bella on macro scale, you're also seeing large
01:37 and nuclei or collections of cells in brain that are performing the same or
01:42 functions. And you're seeing many different outs of neurons. You have over
01:50 different subtypes of neurons which are active that communicate by electrochemical neural transmission.
02:00 produce fast action potentials and release chemical and this is how they engage the
02:07 neurons and the other circuits. They projections that are called axons. There's
02:13 and myelin ated so they can transmit signals along the axon and cause the
02:19 release in the very specialized areas called axons. You have billions of neurons
02:28 the brain that form trillions of Since the computational levels are very
02:37 there are fast slow, ultra ultra slow. The responsibilities of these
02:45 50 different self subtypes are are Also during the development there is a
02:53 more synopses that are present in the . And during the early development we
03:00 a period of critical development, It's period of critical plasticity and during this
03:08 you have a lot of the refinement the connectivity in this neural networks.
03:12 have a lot of strengthening of certain , weakening and pruning or driving away
03:18 synopsis so that your adult brain will a lot less of the synopsis that
03:23 started with. And we know that that process the activity is very
03:28 But so are the genes, there's a debate as in any uh science
03:40 or even theology, the debate of chicken or the egg. But in
03:49 we are trying to understand what this this brain is doing and we don't
03:53 understand everything. So we are having good windows and what the brain is
04:00 . We're really understanding how the brain governent its activity by certain rules,
04:08 certain learning rules and plasticity. So that question of the chicken or the
04:14 , the nature or the nurture? a question of is it the genetic
04:20 that makes us different because the synapses differently. Is it the environment which
04:25 more important or is it bugs? a constant recurring theme in any biological
04:34 evolutionary sciences. If you may, are major divisions and everything in the
04:41 from the neck below is processed by spinal nerves that entered the somatosensory information
04:47 your body into the spinal cord that that information through ascending fibers into the
04:54 stem into the cerebellum and the cerebral . So the cerebral, everything above
05:01 neck is processed by the cranial nerves the brain stem. And obviously all
05:08 the computation and cognition is taking place the cerebrum and the cerebral hemispheres.
05:17 . Again, the major divisions of of the brain. You have 31
05:23 of spinal nerves. So all of information from the neck below enters from
05:30 scam from the drawings and from the is to touch the temperature Itching pain
05:40 all of that information enters from your below the neck, Through the dorsal
05:47 of the spinal cord, the back the dorsal root ganglion that carry that
05:52 to the spinal cord and at the of the spinal cord we have reflexive
05:58 . So if you step on the , you don't contemplate that you withdraw
06:02 . That happens because the dorsal root cell saying ouch this skin stepped on
06:08 nail sends a signal to the spinal . And spinal cord has motor neurons
06:14 come out on the ventral side of spinal cord. Those motor neurons will
06:18 their axons to the muscle fibers saying root ganglion is saying ouch I'm saying
06:25 and withdraw the muscle from the And then of course that information will
06:31 through the spinal cord and will inform C. N. S. And
06:35 you can contemplate about how you're gonna with that problem and the emergency care
06:41 you will do after something like But this reflects of processing and there's
06:47 conscious contemplated processing if you may. The first neuroscientists are coming from prehistoric
06:59 . They're hailing from all over the . So you have parker indians in
07:03 current region of peru Egyptians. A of folks in Mesopotamia that find
07:11 archaeological digs, regular. These skulls these skulls have precise openings in
07:15 And at first the folks were saying , well it's probably because of the
07:20 . So a traumatic brain injury. and in reality they use them in
07:27 have very precise symmetrical shape. You see it's a very precise square that
07:34 been cut out very carefully. So is not an injury. It is
07:39 on purpose. Some of these, are called brain Triple Nations are found
07:45 multiple areas of the skull and what are is they're really opening up the
07:51 and the window into the brain. also the forensics and archaeological forensics reveal
07:59 these interpretations, even in the same , were reopened. The skull tissue
08:06 the skull bone and the tissue around has been reopened multiple times. To
08:12 of course, the earliest interpretations of were that well, it is probably
08:18 sort of a form of shamanism. if a person, let's say has
08:24 health issues then in these prehistoric it was very difficult to understand and
08:30 them without having the modern day imaging and pharmacology that we understand.
08:37 so the interpretation was that the extra surveyed, therefore, the evil spirits
08:43 have taken over the brain to be because you know, evil spirits,
08:47 lighter than air and they fly up the air. And this is a
08:52 of the procedure from prehistoric times. is the tool that would be used
08:56 the brain tra pronation. You have subject sitting here in the middle,
09:00 have somebody holding their hand or their and the prehistoric neurosurgeon opening, doing
09:09 opening in the skull here. This transformations. And since we learned a
09:16 about neuroscience and we know more about . We understand that actually there are
09:22 when you have internal bleeding and hemorrhaging the brain. How are you going
09:27 clean up the blood that is What happens if you don't clean up
09:33 blood that's coagulated brain tissue and keeps or leaking? How do you do
09:39 ? You actually have to get a into the brain. You have to
09:43 the skull and clean the blood, the wound. What if you have
09:49 formation of cerebrospinal fluid which bathes N. S. And is formed
09:54 the venture cults if you have too of that we'll start putting pressure on
10:00 brain tissue, causing pressure on the , causing headache, causing pain and
10:08 deformation about the brain tissue soft tissue if it's in the developing brains also
10:13 skull. Because the skull is solved hydrocephalus and hydrocephalus shaped brains and
10:22 How do you deal with relieving the ? In that case you have to
10:27 to a window into the brain. so the interpretation is such that these
10:34 men or shamans at the time, they were called were probably the original
10:41 and trying to figure out how to problems in the brain with their
10:45 Probably both physiological and psychological in There is a lot of discovery on
10:56 brain by Imhotep and his work is in Edwin smith surgical papyrus. Edwin
11:04 refunded the archaeological digs in Egypt to up Imhotep s writings where he described
11:11 injury cases. 27 of them are drama cases. Uh In those head
11:18 cases, he is talking about distal of the C. N.
11:23 Injury. So somebody had an injury the left side of the skull or
11:27 brain and they cannot control the right or they cannot feel anything from the
11:31 hand. So Imhotep started recognizing the affects a distal control of the brain
11:39 the periphery. The brain is not important, The brain is scooped
11:45 So when you have uh noble noble women, they would modify them
11:54 preserve them but they would not preserve brain. They would literally scoop out
11:59 brain through the nose with the spoon uh tools. They would consider it
12:05 off the skull. They thought the was the most important organ of the
12:09 and they actually preserve all of the except for the briars. Um And
12:17 also came up with the treatment which became modern triage system ailment to
12:24 treated, may be treated not to treated. So I explained, you
12:28 , like another thought in my lifetime there will be such thing as not
12:32 be treated until COVID-19 came in and of a sudden if you have elective
12:39 , wait a year or two, not dying wait to really not to
12:44 treated at least not now to be . So we have not now to
12:48 treated, you know. Um and situation was like kind of a brought
12:55 light with, with covid, People in the hallways in the hospital
13:00 people trying to get their heart surgeries , but no go home, Maybe
13:05 have a heart attack wait for a . It's okay, you know?
13:09 not exactly, but so he designed triage system and why did you do
13:15 ? Because there was a lot of going on. There was a lot
13:18 wars going on in fighting, but these massive structures, pyramids being built
13:25 big boulders, big stones moved, people's hands, legs, heads giving
13:33 a window into the body and the . And that giving a window is
13:39 because nobody could touch human body until renaissance times. It was not really
13:46 to take somebody's body apart even if were brutally injured. So you really
13:54 not know the manual or the build the human anatomy and full and especially
14:01 the human brain, which is difficult a lot more difficult to get to
14:06 to the gut. You didn't know until the renaissance starts personal. So
14:15 window is important. So a lot things that are happening with the brain
14:18 not really by looking into the brain understanding the brain function, but some
14:24 it is based on the understanding of brain functional anatomy, some of it
14:29 still a stock vehicle. Some of is theological interpretations of the mind
14:36 Spirit, soul and Renee the And the western origins of mind distinction
14:45 uh really the person that have defined relationship of mind and body. And
14:54 was not the only one because it happening. These philosophical contemplations were happening
15:00 ancient ancient Greece the mind body to in africa as zapata, mia latin
15:08 India everywhere, people are really trying get at this. He reneged card
15:15 a french mathematician, philosopher physiologist, , He recognizes reflexive behavior and writes
15:24 reflexive behavior and reflex theories. He a picture of a child reaching out
15:28 the fire and withdrawing his hand, about it. The child has never
15:33 about fire. A new baby doesn't what fire is just yellow light or
15:39 light compared to any other light, the second child touches the heat from
15:46 flame automatically, his hand, his , his fingers withdrawn and that's
15:51 It's not taught. So it is . And he also starts interpreting the
15:58 as a fluid mechanical model. Thinking there's something very special with pineal
16:07 He has this whole theory that somehow a connection with the soul through the
16:12 world through the visual system and the that carry that information to the pineal
16:18 because it's in the center of the and from that pineal gland, he
16:23 that there are pipes, nerves that pipes and they carry fluids or gasses
16:30 order to activate the muscles and move body and and even to think and
16:36 and do things. And he comes with, I think therefore I am
16:43 ergo sum phrase. There are ventricles are located in the brain. You
16:50 see that they're very pronounced. And for a long time, because you
16:55 large ventricles, the left and the ventricles that produced fluids and contain
17:01 the cavities that are filled with That's why rene da carts and other
17:07 at the time, trying to interpret brain from the ventricular point of view
17:13 the ventricles are really important. The are very important. There maybe there
17:17 gasses. And so the nerves are out information from the ventricles to the
17:25 . Luigi goal line in the 18th , then demonstrates by using uh laden
17:33 , it's a rotating static electricity He shocks the frog's muscle and the
17:39 contracts and then he shocks the nerve into the muscle and the muscle
17:45 And so he says, nerves actually generate electricity. They can conduct
17:51 They are not pipes in stir. , they are electrical wires.
17:58 Luigi go finally comes up with this concept that our bodies from the,
18:03 the brain into the periphery, a with the nerves that transmit electricity.
18:12 even at this stage in the 18th , we still don't know about chemical
18:18 transmission. Chemical neural transmission Gets discovered proven definitively in 1921. But after
18:28 And this is uh 1760s. So talking about another 150 years before we
18:38 an understanding that these wires, these also excrete on or release chemicals.
18:48 are transmitters. Most of the 18th , 19th century onwards to this day
18:58 really focused on localization of specific brain . And I will recall to some
19:05 you to the new students. I this uh example of phrenology. It
19:12 really ah you can say it's still of the history of neuroscience and what
19:20 to neuroscience being a modern science initiated by joseph franz gall. There's
19:26 certain tenants of the phenomenology is the that looked at the shape of the
19:32 and by looking at the shape of skull. The scientists were going to
19:36 you what features aptitudes. In eight had within your brain. So,
19:43 the book by its cover of central some of the rules were that the
19:48 is the organ of the mind. , there's no more debate about the
19:52 . We got over it. Egyptians thought that. But then the
19:57 Greeks already started considering the brain is most important organ. The mind is
20:04 of multiple, distinct innate faculties. what we're saying now is, let's
20:08 gonna take this brain, we're gonna into regions and we'll say that each
20:14 has a distinct function distinct faculty because distinct. Each faculty must have a
20:21 cedar organ, the size of that . Other things being equal is a
20:27 of its power, meaning that if organ is large here on the left
20:35 some part of this organ, the is large on the left. This
20:40 part will have more power, just with the muscle, small muscle
20:45 £100. Big marcelo lift £200. , the shape of the brain is
20:53 by the development of the various In this case he's talking about the
20:59 and the brain. He's not talking liver, kidney and so on.
21:02 these are the various organs. It these divided into 35 different organs in
21:11 brain. And he has them outlined the surface of the skull which area
21:18 skull does bump on the skull which represents. So the shape of the
21:25 is determined by the development. As skull takes its shape from the
21:29 The surface of the skull can be as an accurate index of psychological attitudes
21:34 tendencies. In other words, these organs in these different areas of the
21:41 he contemplated are responsible for different And if I have a way to
21:46 that bub that angle on the I can actually infer how did they
21:55 ? I didn't even say, confirm determine and be read as an accurate
22:05 . So incredible ability to visualize what human brain is doing below the skull
22:13 looking at the shape of the These are the tools that they
22:17 There's angle measurement rulers. Uh these The procedures that they would use and
22:24 notes. And so you would have consult with a for enologist and you
22:28 walk away and they will tell you your area, whatever. Let's make
22:33 up. 20 was enlarged here. just a very generous person. That's
22:39 innate aptitude and ability is to be generous. So, and of course
22:48 wrong because you cannot read the book its cover. But why it's right
22:53 because it starts talking and printing and a lot of information about how different
22:59 of the brain may contain different areas those different areas are responsible for different
23:06 . So we're for knowledge is we're is that the size of that area
23:11 more power? That's not really the . They were also wrong that somehow
23:17 brain area can actually determine the shape the skull. And they were also
23:22 here unless you're talking about neurological And you're talking about malformation of the
23:28 , either during the abnormal birth defect hydrocephalus or something like that. But
23:36 general, you cannot read somebody's aptitude looking at the shape of their skull
23:41 the size of their brain. And we really start finding out about
23:49 specific brain areas and their functions. the help of paul Broca who discovers
23:57 there are injuries in this area here the frontal lobe located very close to
24:04 motor cortex? The motor cortex is area that will drive the motor commands
24:10 will initiate motor commands, consciousness, commands. So you're sitting there and
24:15 thinking now how I'm gonna say the and when you're about to say the
24:22 is your motor cortex or you're about hit the tennis balls, the motor
24:27 and basal ganglia and other parts of brain that initiate this pattern of
24:33 Speaking of you moving your tongue And joining it with the speech areas
24:40 so on. This is important. he notices that patients that have damage
24:47 Broca's area which is now known as area have a form of aphasia that
24:52 known as expressive aphasia. It means in conveying thoughts through speech or
24:59 patient knows what he wants to say cannot find words he needs. Well
25:06 make a sequence of words. Instead comes out as broken up sentence so
25:14 expressive aphasia and you can think of area of the brand new and say
25:20 this is pretty significant injury. It's it's a big part of the brain
25:24 missing and that's that's right and you kind of express yourself? But does
25:29 mean you can hear and understand everything ? So what happens if you have
25:35 to another part of the brain which called ver nicolas area? You're then
25:41 to have a receptive aphasia which involves understanding spoken and written language. The
25:48 hears the voice which sees the print cannot make sense of the words.
25:53 patients with veronica's damage they cannot make . They can at least listen in
25:59 they'll be able to produce the words they learn how to do that in
26:05 words by reading another way you have economic or amnesia Aphasia the least severe
26:12 of aphasia have difficulty in using the names for particular objects, people,
26:16 or events. Whereas a gnomic or aphasia located, is there an
26:23 So if there's expressive aphasia area there receptive Aphasia vernick Asus area. Where
26:29 the area for gnomic amnesia? Aphasia not in the text box.
26:39 But it will likely involve language And this is also an illustration that
26:45 not only Broca's area and area it's areas in the brain that are responsible
26:51 language comprehension and language production. Not spot in the brain, multiple spots
26:59 the brain multiple nuclei working together into and then producing the speech including the
27:08 cortex. So the vertical say as see it's located closer to the temporal
27:14 and temporal lobe is involved in auditory of listening. So that's why expressive
27:21 to motor control of motor patterns and isn't listening receiving the information? Economic
27:31 . Aphasia would be involving not only language areas but also the memory areas
27:38 hippocampus that you will learn, which important for memory formation and memory
27:44 Global aphasia is a severe form and damage to language areas of the
27:50 Patients lose almost all language function, comprehension and expression. They cannot speaker
27:57 speech nor can they read or And you will say wait a
28:02 So if you have an injury to areas here on the left side of
28:08 brain, the speech areas you don't any speech. Yes, that's
28:13 You will have a significant loss of , but it defends when the injury
28:17 . And so the recurrent theme in course is going to be brain plasticity
28:22 brains are plastic and they can reshape connections, they can regrow their synopsis
28:28 they can also eliminate synopses that are . Another recurring theme within plasticity is
28:34 during early development is during this critical of development is where you have high
28:41 of plasticity because there's chemical environment in CMS in the brain. Trophic
28:47 Trophic chemical factors that encourage the formation growth of new synopsis, the regrowth
28:54 new synopsis. There's also quite a of the stem cell activity going on
28:59 the developing brains. This is something does not really exist in adult
29:06 The plasticity is not as robust it mean that we cannot learn memorize
29:12 but it's finite how much we can and memorize as an expensive forgetting other
29:18 that we've learned in the past The levels of plasticity in the brain
29:23 the adult brains are not as meaning that those same synapses cannot regrow
29:29 easily, cannot reshape the circus as . So if you have extensive damage
29:35 the brain areas responsible for speech in life, One years, 234 years
29:44 age you may have full recovery. if you have damage to the same
29:53 in adult in adult life you will have the same rearrangement. You will
30:01 have the same levels of plasticity and it will result in a more significant
30:08 even complete loss of function in this , loss of speech ability to speak
30:13 perceive the speech. Uh My I used as an example at three
30:23 of age, I had a brain . Meningitis had a stroke and I
30:30 at his ct scans. Maybe I dig them up and show you
30:34 But there was a black hole here hovered over broke us all the way
30:40 vernon cas area, impeding on essentially entire speech area of the brain.
30:49 neurologists and neurosurgeons had a very sobering for him not being able to speak
30:57 understand speech. So he is now years old. And this trilingual and
31:06 has completely recovered. You wouldn't know he speaks three languages and he speaks
31:15 just as good as somebody that lives U. K. Or in the
31:20 but he lives in in Norway So is he an orator? Is
31:25 something that he likes reading speaking? know writing no but can you tell
31:30 this kid had a massive stroke in brain area for the speech is
31:36 So he's lucky because he was three of age. If it happened to
31:40 at three years of age Would have partial loss of speech it would have
31:45 to him at 13 years of More. 30 years of age potentially
31:50 loss with almost no recovery. Uh this is an important theme and this
32:00 another example of Phineas gauge that has a traumatic brain injury. He used
32:07 be an explosives master In 1840s you laying explosives and this is the dagger
32:16 packing tool metal packing tool. He to pack explosives that went off in
32:22 timely fashion and penetrated from beneath his underneath the cheekbone and exited out through
32:29 frontal part of the brain. So through his brain he wants him to
32:35 and people thought that he is dead he recovered and then you would say
32:39 God this is an adult brain as adult human he suffered massive traumatic brain
32:46 huge thing just ripped out a big of his brain. What do you
32:53 ? What happened to him? He die. Did you lose all of
32:57 functions? Did you lose? Did of these functions went down by a
33:03 meaning? Did he lose a part his memory? Part of his
33:07 Part of his feeling? Part of , no Phineas gauge became very
33:13 He couldn't control himself emotionally and he the frontal lobe which is responsible for
33:20 and cognitive and executive control. So of controlling your emotions. And he
33:28 admitted to get his job back. he came back a few months later
33:32 for his job back. So this an example of an adult brains.
33:37 can still have significant injury but it depends where and what function is the
33:43 that that person can walk. He more recommends you can speak, you
33:46 understand, but the executive functions the of aggression it's lost. So different
33:56 parts are responsible for different functions. can have a small injury and a
34:01 loss of function and you can have large injury and the limited loss of
34:06 . It depends on the levels of , it depends on the part of
34:10 brain that has been impacted by a injury. These three uh men are
34:21 for laying the foundation of the modern Camillo, golgi ra Monica hall and
34:31 Carrington. Uh in 1873 Camellia you published a method using silver nitrate
34:40 that allowed to stain for a fraction neurons. But at great length
34:46 Selma's their processes such as dendrites and . Only a fraction of the south
34:53 stain would pick up the silver nitrate and with great uh detail reveal the
35:04 oil and the dendritic projections and the in the brain. So Camellia Golgi
35:12 the person that discovered the same Ramona was a scientist that used this device
35:19 Camera lucida so that you would place stained brains underneath the microscope right here
35:27 he can visualize it in the And there was a mirror projection that
35:32 allow him to draw these cells on piece of paper. It's called camera
35:37 . And modern day microscopy. It's software called neuro lucida that allows you
35:45 do these similar types of drunks using computer controlled microscopes. But you still
35:52 do it by hand. So Ramona draws these beautiful cells and he's very
35:59 . He draws the so most of cells here and he draws the axons
36:04 brown color. And he says that sorry, the dendrites and light brown
36:10 . And he points the arrows saying gun rights must be the place where
36:14 signals are coming into the neurons. other words, these dem rights here
36:19 the base and that the apex are the signals that are coming into the
36:24 . And he thought that soma will will then process the signal and in
36:30 direction will send the signal from the along these darker lines that are axons
36:37 communicate that information to the adjacent neurons the network. He also predicted that
36:47 connections are plastic. So over 130 ago, Ramona alcohol was postulating that
36:56 can change the connectivity between these cells there is a directionality and this connectivity
37:02 that this process and the connectivity between salsas plastic so you can change
37:06 you can strengthen it or weaken And then later Donald have a Canadian
37:13 in the 20th century really put together whole concept of engram that we'll learn
37:19 the cellular substrates of plasticity about which alcohol actually talked about and predicted to
37:26 a great degree at his time when looked on the brain in general,
37:33 brain was translucent and it all looks . And so Ramona alcohol thought that
37:39 of the cells were interconnected. That was a site of plasma continuity with
37:45 of the south in the brain, and spinal cord that they were all
37:52 with one sheet of side of plasma they contained multiple nuclei, millions,
37:58 of these nuclei. And this theory called particular theory. And so Camellia
38:03 was a proponent of that particular The whole brain is a collection is
38:08 census ium Of cells with one common of plasma continuity. And ramon alcohol
38:16 is using his boss's stain sitting there night, crazy habits actually is very
38:23 book, there's even documentary, he's one of the most famous uh Spaniards
38:29 the world. He's a spanish by , neuroscientists really famous. There's a
38:36 institute on neurological dera Monica hall in to this day where he used to
38:44 some really strange habits. We used draw these things and spend so many
38:48 at night drawing these circuits and drawing . And he was a proponent of
38:55 dark train or self theory that neuron believed that these neurons are actually individual
39:02 if they don't have to the plasma , if they're discreet, that means
39:06 there's a space on the queen And he predicted that that space is
39:13 these neurons communicate with each other. it took a few more years for
39:20 Sherington to come and describe this the special place between the two selves
39:28 the synapse and coined the term of synapse and start describing what is happening
39:32 the synapse. So at this we have proponents of ridiculous theory,
39:40 doctrine together in 1906, they accept Nobel Prize for Goldie state or discoveries
39:48 neurosurgeons, but they don't agree. fundamental thing with neurons are discrete units
39:56 it's one continuous thing and that's important ? Because I alluded to it
40:01 I said when finance gauge suffered an where all of these functions decrease to
40:07 certain degree of specific functions and answer functions because if it's interconnected and sensation
40:15 if you injured in one place and whole thing suffers. Well that's not
40:20 the case. There is redundancy and protective mechanisms in the brain and this
40:26 of brain function. So you have , we're a couple of areas to
40:31 nuclear processing the same or similar. if you injure one, you'll still
40:35 one or two more, you'll have chemicals. So three chemicals mediating the
40:40 process. So if you have a imbalance and one is gone, you
40:45 have a backup. It's a it's pretty it's a pretty clever system.
40:49 self assembles itself pretty well during early and it's a pretty pretty clever system
40:56 in protecting itself and and and allowing to do the things that we
41:02 Modern democracy copy that. These units definitive. Doeses't show us until you
41:08 electron microscopes in 1950. So you actually visualize completely these cells without any
41:14 using electron microscopes. And at the of the 20th century, very
41:21 And then talk about the middle of 20th century. only in the middle
41:25 the 20th century, you start understanding recording action potentials. So we have
41:33 gorges. We have electricity in the . Okay, we have ramon
41:41 there is a flow of this electricity different directions, There's circuits, there's
41:46 . There's synopsis, there's plasticity but don't understand what that electricity is but
41:53 don't see discrete units without the stain . So, when we come back
41:57 the following lectures will understand how these neurons start producing action potentials, communicate
42:04 each other, the diversity of their and how glia is the most prevalent
42:10 of cells in the brain, not , but glia. How do we
42:15 a very important role? Not just role, but proactive role in controlling
42:20 transmission and synaptic communication and plasticity in brain. All right. Any questions
42:28 today or in general? Just a that we will be online on
42:37 So we will do it this monday the following monday. Mhm. And
42:44 will see you back in class on when I was coming back in
42:48 On Wednesday. If you guys have issues with materials, let me
42:56 And I will give you the video for the materials later this week.
43:02 no, sorry, this is the . So by monday I will inform
43:08 and you will have the information on video links and if you haven't taken
43:11 course with me, I typically run through how it works and it's not
43:16 perfect system, but it works pretty . All right, thank you very
43:20 , Apologies for some technical issues, I think we're off to a pretty
43:24 start. We finished
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