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BIOL 4315/6315 Neuroscience Tue Th - NEURO Lecture 02 History of Neuro II
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00:02 This is neuroscience lecture two. We continue talking about history of neuroscience and
00:07 we will talk a little bit about infections in the cns. Now we
00:14 that the nerves produce electricity, that no longer the pipes. We thought
00:20 ventricles were the most important part because were filled with fluids and we thought
00:24 the nerves were pumping the fluids. since the discovery of the nerves as
00:33 signals, there's also growing field and need to explain what are different parts
00:39 the brain are responsible for. Or it that all neurons in all parts
00:44 the brain are responsible for all of functions? Just a small extent.
00:48 so when you put everything together, get the full function for everything.
00:53 one neuron is really responsible for all the functions just a very small
00:58 That is not the case. And people are observing inside anatomy of the
01:05 , but they're also observing the outside of the brain. As you're
01:09 your scholars soft, your skull plates not fused together. If you have
01:16 infant in the family, you can the top of their heads, you
01:22 touch the top of your heads and see this flat soft spot. This
01:26 where your skull plates fused and there two spots, one here, one
01:31 the back and with little infants. really scary because when you put it
01:35 it's not even hard, it's actually , like a membrane because the skull
01:41 is shaping and it's grown, the and the body are shaping and the
01:47 to the skull bone is also So, because the skull bone is
01:54 , there are certain conditions, neurological such as hydrocephalus where you may have
02:00 accumulation of fluid in the ventricles and the ventricles and swelling of the brain
02:07 . And as the child develops, this condition is not being treated,
02:12 fluids will push on the brain the brain tissue will push on the
02:17 tissue and then hydrocephalus, if it's , would form these what we envision
02:24 like large heads 30,000 years ago, very likely maybe that you needed to
02:32 the skull to drain those fluids and treatment for hydrocephalus is such that you
02:37 to drain these fluids. The point that the soft tissue of the brain
02:42 pushing on the soft tissue of the and therefore it's reshaping the scot.
02:47 franz, joseph gall and for knowledge start really looking. Is there scientific
02:53 , is there some sort of a way calculations that we can do on
02:59 surface of the skull and they decide the brain is the organ of the
03:07 ? No debate there? And the is composed of multiple, distinct innate
03:11 . So they argue no. They that each part of the brain is
03:17 for specific functions, They argue it's not all neurons are responsible for
03:21 . We have to divide different parts the brain and we have to assign
03:25 functions to each different part of the , whether it's uh innate characteristic or
03:33 ability and so on. So Ologists say the mind is composed of
03:38 , distinct faculties because they're distinct. faculty must have a separate seat or
03:44 In the brain. And they say there are at least 35 CSR organs
03:50 the brain inside the skull. They the size of an organ. Other
03:58 being equal is a measure of its . Small biceps, £10 big
04:06 £50 power, bigger muscle, bigger . They go there. They say
04:15 if you have a certain ability, have a certain innate characteristic or develop
04:21 that you're so good at. Like for example, you're the most generous
04:27 I've ever met in my life, that part of the brain is gonna
04:31 enlarged and by the fact that that of the brain is gonna get
04:39 the stall. The shape of the will reflect anatomically this larger part of
04:47 brand that's responsible for generosity and the of the brain is determined by the
04:54 of this various orders. As the takes its shape from the brain,
04:58 surface of the skull can be read an accurate index of psychological aptitudes and
05:07 . So these organs inside the brain responsible for different intellectual aptitudes and characteristic
05:17 . They take the skull and they 35 areas on the skull and they
05:25 underneath the each one of these areas the skull there's brain tissue, there's
05:30 organ and that organ is responsible for function. It's actually quite foresight fel
05:36 you're trying to incorporate the psychology, characteristic that the traits, intellectual abilities
05:47 then a trades potentially. So a of things is going on here.
05:52 I guess in the you know, you walk into for enologist office and
06:02 the monologist uses these kinds of tools will measure the circumference of your skull
06:13 . And it will basically We create outside of your skull with these measurements
06:21 we'll give you a not sure if can be called a diagnosis or your
06:29 of the ability saying that yes, . Area 22 here or area doesn't
06:35 seven. There's a bump there and generosity area. So you are indeed
06:40 very generous person. Mhm. okay, what are some of the
06:46 things in here? The good things here that some things on the skull
06:50 be reflected by what's going on inside brain. But it's usually typically during
06:54 early development and it is typically tied neurological disorders but not with aptitudes and
07:00 that are represented by a normal bump the skull on one side of
07:07 Alright, what do they not have for them? The size of the
07:11 , the size of the organ. being equal is a measure of its
07:16 . The bigger the skull, the the brain, the bigger the animal
07:23 elephants have the largest brains. They be the smartest. But is there
07:31 truth to larger parts of the We there's some truth to that.
07:35 you are an animal that lives in environment that needs to perceive certain
07:41 stimuli, that part of the brain develop more and anatomical will be more
07:47 than other parts of the brain. fact of the matter is that where
07:50 were misstatements? You cannot read the by its cover and you cannot read
07:56 surface of the skull and these anatomical um measurements as a representation of anything
08:05 physiological or even the aptitudes that they've . However, if you walked into
08:11 library at the time point 2nd, is happening with my if you walked
08:26 the huh You walked into the library that time, 1848 you would see
08:38 technological journal and they would be very discussions about what parts of the brain
08:44 responsible for what faculties and functions? can we measure it on the outside
08:49 the skull? It's an involved science major publications that can be found
08:56 Um Is this where the idea that are not as far as men came
09:01 ? Because most women have smaller heads men. I know that some neuroscientists
09:06 that era about that I have a man, I don't know if that's
09:13 it came from. But I mean there were a lot of bad gender
09:19 that uh that were not true something true. So uh now we're still
09:27 much interested what the brain does not what the skull looks like and what
09:31 can predict from looking at the And the early discoveries of specific parts
09:37 the brain that are responsible for specific came from the loss of function studies
09:43 the person was losing a certain ability losing or not having a certain
09:50 So paul broker doctor paul Broca has patient that has expressive aphasia in expressive
09:56 you have difficulty in conveying speech through or writing. You understand things,
10:05 can think about things you can still write, you can still even speak
10:12 it may not make sense. The of words may not make sense.
10:15 sequence of written things and they may partially written. So is the whole
10:21 affected no specific function and speech express is affected. And dr paul
10:27 postmortem after death looks at the patient's and he finds a hole in this
10:33 . So he writes letters to all the scientists, there were no
10:37 cellphones, horse buggies trains and he the scientists asking have you experienced the
10:44 that can understand speech but cannot express properly. And soon enough he gets
10:51 from his colleagues and he gets postmortem shift into him and all of his
10:59 that he reaches out for and has a missing part of this of this
11:06 in the brain has an injury that occurred in this part of the
11:09 And patients of all exhibited expressive evasion time later later. There's a discovery
11:17 vernon this area here and people that have damage to veronica's area are susceptible
11:24 have receptive aphasia which involves difficulty in spoken or written language so you hear
11:33 that you're missing hearing you see the , but you cannot make sense of
11:38 words you can actually speak if you make sense of the words, it
11:43 on what time in life it happens sort of injured or something like
11:47 Obviously it affects your ability to understand also express yourself but you can produce
11:54 speech. So it's a receptive there's also economical amnesia. Aphasia,
12:00 the least severe, severe form of where you have difficulty in the correct
12:05 for particular objects, people, places events. Sometimes it's transient before you
12:13 your first cup of coffee, you remember who you're looking at or you
12:20 remember somebody's name, you met yesterday then it kind of all floods and
12:24 a lot of these things are also by other things. The circumstances,
12:29 other cues that you may have experienced you met that person or saw their
12:33 or heard their name and so But there is a severe form of
12:37 , global aphasia, it results in and extensive damage to the language areas
12:43 the brain, patients lose almost all function, both comprehension and expression.
12:49 cannot speak or understand speech nor can read or write. What does that
12:55 you that? Once we discovered that brain specific areas of the brain is
13:02 for specific functions, we also discovered it's not one area of the brain
13:06 broke this area that's responsible for It's not two areas brokers in
13:11 this area in the brain that are for speech. It's multiple areas on
13:16 brain that need to be engaged properly engage the motor cortex to produce the
13:23 output that is being generated in thoughts our heads. And so you have
13:31 have extensive damage here in order to all of the aspects of the speech
13:40 we're discussing here and experience global My nephew at three weeks old had
13:48 stroke and when we looked at his tomography, ct scans had a big
13:56 here in his brain. And the and neurosurgeons at the time predicted that
14:03 likely not going to be able to speech or express himself properly because it
14:11 in this specific area more biased. damage was wider than just broke this
14:17 , but it was more toward the and temporal border here. So I
14:25 to report to you that my nephew 18, he started college and he's
14:34 , okay. And uh he's not orator but he's trilingual and that's that's
14:43 remarkable and you will say why why does that happen? And there was
14:49 severe damage and there's a He by the way, you know,
14:54 was a child three. So you , it's not like he came out
14:58 the coma and surgery and started speaking he never spoke. So the recovery
15:06 partial recovery of this loss of function this case it's almost complete recovery of
15:11 loss of function. Why does that ? Because the brains are plastic?
15:17 plasticity in the brain, there's the for the axons and neurons to reconnect
15:22 each other. Sometimes when one part the brain is lost, the other
15:28 of the brain can take over the space. Sometimes if you lose an
15:34 sense such as hearing, you start more on other senses, You start
15:42 training more of the other senses. if there is sufficient enough plasticity in
15:46 brain, you can actually become better at seeing things because you lost
15:54 you can become better at smelling things you lost vision and you have to
16:01 a lot more on potentially the sense smell depending on the environments that you
16:06 in a work environment for example, that where the fluid is, you
16:12 , that's a big machine standing there you know where the air freshener
16:17 that's where the bathroom is. And in fact I was, I was
16:22 like this semester they asked us not give a project to students and I
16:27 went like, oh no way I the best project for for for,
16:32 wanted this project to be actually a or two year old long project that
16:37 just kind of pitched in as a text. I've just got a couple
16:41 extra credit points but I'm not gonna it because they asked us not to
16:45 group projects, but it's my standing to come up with a map of
16:51 of age that I call the sensory of University of Houston, it's a
16:58 of the blind, it's a map the death and it's a map that
17:04 based on as many sensors as you imagine. Sound smell, temperature and
17:10 like that. And I was gonna students to start working on an area
17:15 how would they create that map and on the actual physical architectural map of
17:22 campus buildings where a person that you have to put yourself in their shoes
17:29 have to find different rooms and what the cues that you would put for
17:34 person if they were blind, if were deaf? If they didn't have
17:40 sense of touch with queues, would put for that person that students and
17:47 to navigate police maps is an interesting . Yeah. Okay, we won't
17:55 to work on that. But that's that we can imagine and and that's
18:00 that we should think about all the and feel lucky for for having most
18:05 us having all of these abilities. , Phineas gauge is probably the most
18:11 subject in neuroscience. Phineas gauge was charge off packing the explosives as new
18:19 railroads are being laid through the They need to cut through the mountain
18:25 the rocks. And so they're laying , exploding the rocks and laying the
18:31 says gauge has a massive injury. he's packing this is the dagger device
18:39 is used to packing explosives like dynamite such into the rocks. S he's
18:45 the explosives. An accident happens, explosion goes off accidentally and the
18:54 this dagger penetrates underneath it all takes out his right eye and shoots
19:05 and exits out through the front of brain. Very large injury, sustained
19:14 in the final cortex, adult or a child. And the reason why
19:19 say that is in in adults and grown and and then in aging
19:24 your plasticity computers off and you have and less plastic brains and less and
19:29 chance to remember less and less chance rebuild that loss of father massive sustained
19:36 in the brain. The question becomes is probably dead. He's not,
19:45 of months later he comes back to for his job again. You can
19:53 lost God, you can hear, can speak, he can walk,
19:59 can think he can ask for his back. They don't give him a
20:02 , he can soften people. They he is just can't control his temper
20:07 is really aggressive. So this suggested scientists that there are parts of the
20:14 that are responsible for producing speech or for seeing. And then there are
20:20 of the brain that control personality, control executive function that control emotions.
20:28 if you have large parts of the taken out during traumatic brain injury,
20:36 have still a lot of these functions that will allow you to live.
20:42 an ongoing debate actually how aggressive finance was. There's one account of him
20:48 to Mexico murdering a couple of people on a sailboat and sailing back to
20:53 think Portland baca, that part I up. But it's a pretty cool
20:58 there. Uh, in the south coast of texas by some other counts
21:07 psychologists and scientists. He's not so . Is not that aggressive person that
21:14 described. So the debate was really out. What, what kind of
21:18 , how extensive the damage, uncle and the sun. What year was
21:37 ? Yeah, lose pasture. So , just patch up. I
21:45 they used what they could, you , they probably suit, you
21:49 and put in and, you honestly at some point, probably when
21:53 found him there, like, I know, we can do much about
21:56 person, but they did. And he was breathing probably. So you
22:02 uh bled in the brain to death that could have happened and probably preserved
22:08 hard enough to sustain the most of brain function because the brains are very
22:14 to loss of oxygen. So you have somehow maintain the heart function and
22:22 . I mean, based on the , I think being hard on him
22:26 he's just angry and didn't have anything saying regardless of what part of the
22:32 was damaged, just the kind of will make you angry, hopefully not
22:37 other people. So yeah, so gauge demonstrates the modern neurologist said,
22:45 , there's these very important sensory processing of the brain, emotional parts of
22:50 brain, character, traits, executive , parts of the brain. Only
22:56 we get into more details when there cortical stimulation studies that began in the
23:02 and 20th century. So we start a little bit more about details and
23:07 of a, from macro scale, lobe versus occipital lobe, more into
23:13 precise networks in the brain to Charles I mentioned because I already alluded to
23:20 plasticity and this plasticity I imagined as evolutionary plasticity that we're all going
23:28 And so Charles Darwin studied it in and turtles and he, what he
23:34 is different environments in the islands in Galapagos that they had different eco climates
23:44 . And there was somewhat different. these animals had to lead to in
23:48 to survive and procreate had to have little bit different shape in their in
23:54 beaks, if there were birds that to have a little different shape and
23:57 fins if they were fish. And this is an example of how in
24:03 to survive in the environment, your anatomy adapt to that environment. If
24:08 had to swim to school 20 miles day, you probably have really strong
24:12 body. If you had to run school 10 miles every day, back
24:17 forth, you probably have really strong body and and so on.
24:21 but that's beyond that certain animals, example, rats, they live in
24:27 where they get by with some matter and smelling so faction and whisking around
24:35 faction of smell and look at these , these olfactory bulbs in the front
24:40 the brains and you can see how these olfactory bulbs are compared to the
24:47 size of the whole brain. These bulbs account almost 1/5 of the entire
24:54 cerebrum mass. That is dedicated. means that that rat spends a lot
24:58 time smelling, that rat also sends lot of time to look at These
25:04 all factor involves in nonhuman primate, still being, we still have very
25:12 sense of smell, but that's not we really primarily rely on in our
25:18 in order to survive and procreate hearing all of these other things.
25:23 were intellectuals to. The other thing these rodents do really well is they
25:29 around and as they whisk around, look for food mates and so on
25:36 and their map, their their map how they're browsing through the rooms of
25:40 or holes or uh metro, underground and stuff like that. So what
25:47 animals have is a lot of their space will be dedicated to Samata sensation
25:53 these whiskers. And we'll study some of sensory cortex and somatosensory system in
26:00 . But you see these rows of , we call this the barrel
26:07 each one of these barrels processes information a single whistle on the whistle
26:13 There's a very precise and sophisticated anatomy animals developed for their whiskers because their
26:21 depends on it. Do we have whisker map? You know, it's
26:31 different. We don't rely on on on getting by whisking around. So
26:38 part of the brain is not going be as the plants too much.
26:42 what Charles Darwin observed with these outside , how they influenced your external
26:48 We influence our brain anatomy. Als I always use this example maybe three
26:56 four times during the course I asked you know we said that there are
27:00 maps for different activities. I will to this. So actually will bring
27:05 subject in a little bit of the most famous neuroscientists probably Camelia Golgi and
27:16 . And these people are very important also what is happening in the
27:21 What is happening on earth. And development of the technology concurrently is very
27:25 . Prior to 19th century microscopes were quality and the first microscope that can
27:32 a single cell that means it has resolution powerful enough to see about single
27:37 is about 10 micrometers In diameter. comes about in 1820s really in the
27:45 19th centuries when people start studying and at single selves in the early 19th
27:51 , anonymous noted that the brain appeared a capillary vascular system for nerve
27:57 If you took the brain out it kind of a pinkish and it looked
28:03 it was all together. And if made slices from that brain that you
28:08 took out and you put it under microscopes that kind of translucent and you
28:14 didn't see individual neurons and boundaries between neurons. So as the scientists take
28:19 brain out, they said well you what we think that the C.
28:24 . S. And the brain is census. She um which is a
28:28 of living material having multiple nuclei. don't know how many thousands,
28:33 billions and cytoplasmic continuity from one place the network to another. Meaning that
28:39 reticulated theory was dominated by this belief the whole brain is one mass surrounded
28:46 one continuous cytoplasmic sheath that's containing multiple within us. And the opposing view
28:57 the neuron doctrine. Also the South in biology how the nervous system,
29:02 all other biological tissues, is comprised discrete cells called neurons, each with
29:08 one nucleus and surrounded by cell How do you prove that you have
29:14 visualize neurons? When we say neuroscience , in the brain is mostly in
29:20 stain like the rain in spain is in the plane and Emilio gal ge
29:29 1873 publishes a method that he applies in that time, photographic development of
29:39 In the 20th in the 19th beginning of the 20th century, silver
29:45 free agents were used to develop the from the film. And this is
29:51 beauty of being a scientist and being anonymous is familiar goals. You're probably
29:57 down to get his favorite italian coffee running into somebody who is his
30:05 a photographer that is making his family and says I used this chemical silver
30:14 and camelia goal just says, I'll take it to my lab and
30:17 it on the brains. That's what can do as a scientist. As
30:23 as you're compliant with regulatory or whatever can take stuff that nobody has done
30:30 . People are using in photography. put in the brain, he puts
30:35 in the brain and he develops this with the silver nitrate stain. And
30:40 now called Golgi stain. And golgi gets taken up a very small fraction
30:46 neurons, about 1 to 3% of of the neurons in the brain.
30:51 the slices take up the Golgi But those neurons that take up the
30:56 stain, they stay in the they reveal the den rides, they
31:04 the axons and external projections in a great detail and gold just ain't today
31:11 one of the best stains to do reconstruction to the full morphological description of
31:20 . Because all of the processes are clearly demonstrated. Musicologist. I don't
31:26 exactly why. Only 1-3% of the take it up. But it was
31:31 gift because if all 100% of neurons up the stain there would be so
31:38 overlap in the images between this You can imagine that there's probably 1000
31:45 or 100 neurons. If it's 123% . So it's 100 neurons between these
31:51 . What if you expose all of 100 neurons and their processes? You
31:55 wouldn't be able to see very So it was it was a gift
32:02 the for the scientists ra Monica hall here is Community Goldie student, the
32:09 famous spanish neuroscientist. There's a institute neuroscience named after Ramon alcohol. And
32:16 alcohol uses this Golgi stain in the and he uses a microscope. And
32:26 microscope is a special microscope that is camera lucida. And it has a
32:32 of mirrors that reflect what you see the slide through the eye pieces there
32:39 a set of nerves that shows your over what you're looking at the slide
32:46 you have to say, well how how did Ramon was the one that
32:49 these drawings? This is Ramon alcohols . How did you draw? You
32:56 if you see an artist like look the slide was like no. So
33:02 you use this camera lucida mirror subset allowed him to precisely trace this is
33:11 tracing. This is not a made drawing your tracing the boundaries of these
33:17 . And the process is because you visualize the stain cells and you have
33:22 subset of mirrors that allows you to your finger and the pen over that
33:28 over that south and modern days this called. And computers can draw cells
33:36 these images. The humans are still best. Even using the computers.
33:41 now the pen and the set of built into the digital platforms and you're
33:48 a mouse instead of a question. a great question. I'm not certain
34:03 here. The contrast I was was for angiography. Uh and that's actually
34:11 should know. But I want to it was the beginning of the 20th
34:16 for the angiography contrast dye, because were X rays in order to visualize
34:22 angiography dies. Uh if you're talking just the blood vessel staining, maybe
34:29 was something there. Uh but and . That is a really interesting story
34:34 . I should remind myself with It happened because the guy that developed
34:38 contrast which is used into the interventional used into the ct scans and contrast
34:45 all that set off. So you visualize all the blood vessels and things
34:48 that. Nobody believed him, but working. So he got his
34:54 he injected himself with a contrast. his nurse walking. It's not a
35:00 procedure. Walk into the X ray take a picture of his answer.
35:04 , I told you can see all with other people like. So,
35:08 sometimes takes a lot to prove And actually, this is also related
35:13 this story to Sir Charles Carrington described synapses, and we'll come back to
35:19 in a second. How this is to this story is Camelia Goldie's a
35:25 of particular theory. So he discovers state he sees these discrete individual
35:32 but he still argues for a particular . His student Monica Hall is the
35:38 proponent of neuron doc chain. Not that he says, you know
35:43 It's more than that. It's not all Cida Plaza is that these elements
35:48 . Done guys, they're like they're going to be receiving the
35:51 That's his interpretation. All the signals flowing in. Something happens in the
35:55 . This is the Monica halls something happens in the Soma. Is
35:59 information that gets received by antennas which rights gets integrated and processed by the
36:05 ? He said even more. So information that I think these things is
36:10 that sends the information to other They're different from antennas. So to
36:14 I'll units and we now know them axons that actually conduct electricity and then
36:21 neurotransmitter onto the incorrect interconnected neurons in brain. And ra Monica, how
36:30 that these connections are plastic. you have the boss, it says
36:40 particular theory, And you have the that says, no discreet units communicate
36:48 each other. Plastic communication can change their rivals about this the land.
36:54 in 1906 day, they accept the prize together. So, the reason
37:00 I said the story relates to is somebody took a lot of pushing from
37:04 this guy to really make the field that it is neuron doc train and
37:11 like the guy that did the angio dot So we now, you
37:17 we're thinking that legion kobani electricity. . So he's thinking electricity. So
37:26 some flow of electrical information, He's about that but they don't know that
37:33 generate action potentials. And that's something gets discovered almost in the middle of
37:38 20th century. Yes. Sorry, didn't see your hands. I cannot
37:44 you. Sorry. During the Absolutely. Just like this cell cell
37:55 turns out being individual discrete units. search health point synapse praises a specific
38:06 between the two selves with the communication place and he started trying to describe
38:11 what processes this communication would take Yeah. So this is a modern
38:17 view. It's a lot more complex . Uh And there were more stains
38:22 were discovered to gain more information into brain. And this stain is in
38:27 cell stain. It's very different from stain. This sustainable stain all of
38:32 neurons and all of the glia in whole cerebrum. But when it stands
38:38 it doesn't really reveal their processes very . So you can anatomically maybe distinguish
38:45 neuronal shapes and leo shell shapes. not a very reliable way to do
38:50 . You can but you really don't the processes of these cells. But
38:54 you do see is you see all the cells which means it gives you
38:58 map of the densities gives you the these are six layers of the lateral
39:05 of the thalamus. It's the station processes visual information inside the brain in
39:11 thalamus. And you will know all these six layers When we study the
39:15 system 123456. And the cells that in these layers are more dense and
39:23 cells and these layers have a certain architecture of stacking. It's referred to
39:29 the architecture and this structure over This is the hippocampus and the
39:37 Although it's a three layered structure, has a very dominant one layer that's
39:42 populated with with neurons in hippocampus. will use multiple times in this in
39:49 scores discussing hippocampus. The hippocampus is very important structure that's responsible for memory
39:56 memory, recall. It's also part the limbic system involved in emotional information
40:02 and the memory the hippocampus deals with the storytelling, storytelling memory or semantic
40:12 . So comedian Bodman, broad Dr bradman uses the nestle stain and
40:18 methodically stains hundreds of human brains and slices hundreds of human brains and he
40:25 the map of the brain which is site or architectural map of the
40:31 These sat architect tonic maps by describing observing these variations in the structure of
40:40 cells in the densities. The packing in different areas of the brain in
40:46 architecture, vertical versus horizontal stacking and shapes basically determine different functional areas in
40:56 brain. And so to this Area 17 is the primary visual cortex
41:01 we know that area 17. That described by dr bradman is a different
41:08 from area 18 Also described by dr . These are non functional maps.
41:14 anatomical site, architect tonic side architectural of the brain. But they were
41:20 precise and that's exactly what we Not the foreign ologists outside of the
41:26 designations of 35 areas. But this precisely what we needed. We needed
41:31 precise anatomy inside of the brain by that side of architecture anatomy. We're
41:37 now applying different functions for these different of the brain. Uh Like microscopes
41:46 resolve about 0.1 micro meters in resolution they can resolve modern light microscopy individual
41:55 cells but they cannot visualize synapses. synapses or the space between neurons is
42:02 nanometers. And to visualize synapses you a lot more powerful microscopes that are
42:09 lot of term microscopes. And electron can visualize the resolution of 0.1
42:17 So you can visualize synapses and you really see what's happening between axons and
42:24 and such. And when ra Monica did these labels on the south,
42:30 revealed that some of these dendrites that drew also had these mini protrusions and
42:38 mini protrusions became later known as dendritic and their tiny little protrusions that come
42:45 of the spine. And this is most of the synapses in those receiving
42:50 in the dendrites of form. So synaptic alie on the dendritic spine.
42:57 synaptic lee. This is the dendritic Right here. D. M.
43:02 dreaded spines will have post synaptic densities PSD. These post synaptic densities are
43:11 of post synaptic protein receptors on the membrane. You can see juxtaposed to
43:18 P. S. D. On the opposite side. You have
43:23 axons, these axonal terminals and inside axons you can see these circles some
43:30 them are filled with red and others to be like empty red circles.
43:35 are neurotransmitter vesicles that are present in axonal terminals. So if the axon
43:42 d polarized enough it will release the by fusing the vesicles to the plasma
43:49 , releasing it into the synaptic space then binding to the post synaptic densities
43:56 the receptors on the dendritic spines. this is post synaptic and this is
44:02 axon is pre synaptic. You can that these dendritic spines are carrying different
44:09 . A. Is study spine Is a thin spine. C.
44:17 a mushroom shaped spine. This is very large spine here that you see
44:22 is mushroom shaped. Okay interestingly enough larger spines may have multiple posson opic
44:31 . One 2 3 formed on the On the same dendritic spine. This
44:39 one synapse on one dendritic spine and is three synapses from one dendritic
44:46 So the shape and the size of dendritic spine will also determine how much
44:52 . For example it can receive a . Very interesting thing about the
44:57 They have stores of their own energy the form of Mitochondria and and 80
45:03 . Which is the main source of for the cells. In addition it
45:08 smooth into plasma particular and by that by having the energy stores and having
45:16 ability to do some of the post work locally and just single one localized
45:24 spines makes them somewhat biochemical independent off main dendritic shaft and off the entire
45:33 , which you know that most of biochemical machinery is happening at the level
45:38 the selma's and the supplies of energy coming from the soma. As these
45:44 also the most plastic elements. Dendritic can grow. Dendritic spines can
45:51 Dendritic spines get pruned and when we born during early development we actually have
45:57 lot more than Ridic spines and a more synapses. It's as if our
46:03 is everything is almost interconnected everywhere. then during the early development we actually
46:09 refinement of these connectivity ease. We pruning of the synopsis and strengthening of
46:15 active ones and reshaping the circuits and that's a lot more precise and has
46:20 synopsis and an adult human being than you were born with it. And
46:29 we reshape these dendritic spines. You say that today you just learned something
46:38 and in order for you to learn new, there has been new communication
46:44 two neurons, the pre synaptic and synaptic and maybe if I repeated it
46:50 many times and came back and repeated again with that synapse actually becomes functional
46:58 strong and that you remember that Luigi is by electricity in your arms.
47:05 the honey. That's a synopsis for alcohol. No, sorry, this
47:12 goldie Ramona alcohol and search all Okay, does that does that make
47:19 ? What I'm saying is that we these new synapses, we build new
47:24 . It's not static that brings of when you're learning things, that's precisely
47:28 you're doing. You're establishing new You're strengthening certain connections and possibly at
47:34 expense of other connections to other things may have been occupying your mind before
47:39 walk in this classroom. So when born, did you say that um
47:45 that we have more injured expands. was less effective at processing the
47:51 Yes. During the early development there's synopsis. But then as you mature
47:58 engage different sensory and intellectual stimulations and emotions that there's a refinement and many
48:09 the circuits in the brain are overlapping the beginning and later they segregate and
48:14 themselves into being anatomically more precise anatomically sophisticated and therefore functionally more precise and
48:24 more sophisticated too. Um the good is sometime in the 20th century,
48:33 came up with infrared cameras. And reason why it's the good news is
48:39 infrared cameras can allow us to digitalize without stay anyway. And so this
48:46 something that you would see in a electrophysiology or neurophysiology setup where we study
48:54 in brain slices or in vitro versus vivo as a whole brain. So
49:01 take the brains out with a Um we slice them about 300 micro
49:07 stick and we place them under the here and you'll say, okay
49:13 So what does this slice? What the cell need in order to
49:18 So this slice is sitting in the here, there's artificial cerebrospinal fluid our
49:26 and neurons evade by cerebrospinal fluid. artificial cerebrospinal fluid dating with slides that
49:34 is oxygenated. That means that animals supply is still coming. And so
49:42 telling the slice, you fool, still a part of the brain,
49:48 getting the oxygen, you're getting to a set hang in there for about
49:52 hours and these cells are alive. course you can think of like it's
49:57 massive traumatic brain injury that you've just , isolating a slice of the brain
50:01 a microscope. And a lot of neurology and neuroscience discoveries come precisely from
50:08 kind of work and they don't necessarily have to do with traumatic brain injury
50:13 rather basic neuronal function and synaptic function synaptic plasticity and such. So we
50:20 visualize these neurons. We can now micro electrodes whether they're glass. This
50:25 Boris silicate glass micro electrodes. This 10 micrometers. This is one micro
50:31 in diameter tip of the micro Now we can study individual no
50:37 we can study their electrical activity. can apply substances, pharmaceutical substances,
50:43 , unknown chemicals and toxins and see they affect the basic function of these
50:49 . We can also look at the but disability is because you have I
50:55 if you would just look again through eyepieces here, we don't have infrared
50:59 . So we have a set of mirrors that will send this image into
51:06 back of the microscope into the infrared that is connected to monitors and computers
51:13 . But when we first started, know this infrared microscopy and this particular
51:20 is also referred to as patch planting or electric physiological recordings or uh neuro
51:28 recordings. When I started my neuroscience in 96 this was still like really
51:35 just coming on like hot. Like wasn't like we just had one or
51:39 locations. Almost every university had a like that. It was still
51:44 We were buying our monitors from the security camera guys because we were not
51:51 into directly to digital and so But this really ushered a new era
51:57 being able to study information in vitro you study the whole animal or before
52:04 take it up the chain. And is a real functional information from electrical
52:09 to chemical activity from single cell to networks that you can visualize and study
52:16 activity. Now, this is where gonna remind myself, I was gonna
52:22 you something modern view of neuroscience and of analysis. A very, very
52:28 and you can look at something that's molecule and trace that one molecule.
52:35 activity of that one molecule, neurotransmitter , maybe kindness or enzyme or foster
52:43 or whatever. Or you can have non invasive view of the brain and
52:51 view of the brain basically. What the different functions that are being performed
52:56 the person is performing different tasks? ultimate in the clinical world, the
53:03 knowledge base that we're striving. And believe it's probably possible if aliens especially
53:08 us in this 21st century. What possible? I think it's possible to
53:15 to a single solid single synapse level performing a cat scan or pet scan
53:23 FM Mariah, the whole brain. is something that is missing. When
53:28 go into clinic, when you're being for things, you don't see a
53:33 cell resolution from our eyes, cannot resolve single cell positron emission tomography cannot
53:41 single cells In the lab, we resolve single cells, we can activate
53:48 cells and so on. What is 21st century is merging this with this
54:00 can we do it non invasive. we get to the speed when they
54:06 these cancer? Not necessarily very fast very large machines, processing time takes
54:12 just like the computer to buddha. we make it as fast as neurons
54:17 milliseconds real time? Can we drive down to a single cell resolution?
54:28 this is the this is the bioengineering mosque neuralink. However, let's do
54:36 okay because this is this is really very important and these images, you
54:42 these are our spines, dendrites and . You can see how spiny they
54:48 . The single cell can receive hundreds thousands of inputs that sell this very
54:53 computation within milliseconds and decides that it's communicate to other networks involved, other
54:59 . This is a pet scan of you when you're looking at words,
55:03 engaging your occipital loan, This is sensor information processing of looking at words
55:09 you're listening towards the temporal lobe, information and temporal lobe is engaged.
55:17 you're speaking of words you better be close to Broca's area and motor cortex
55:24 that that's what produces the speech pattern sends it out. But look at
55:29 this map of activity is different when thinking of words and in general what
55:36 are. These are maps of So there's a site of architecture,
55:40 certain architectural design in the brain and top of that side of architecture you
55:47 activity in individual neurons and the networks neurons and you can look at the
55:53 of neurons that are activated during different . So you can see that when
55:58 person is thinking of the words? occipital lobe is no longer actually engaged
56:02 they're not looking at the word And so you have these local brain
56:09 , they get more active or less . This is like a brain map
56:13 activity map for an ongoing task And say so does that mean that I
56:19 only use 10% of my brain and don't use as much of your brain
56:25 you can. However, if you 100% of his brain wide up You
56:32 to go to emergency room because you're generalized epileptic seizure in about 45 minutes
56:38 live this amount of energy. This of excitability and chemical exchange cannot be
56:45 at 100% with the sweet spot. don't know. Do we multitask at
56:51 and go down to 30. What when we're asleep? You know we're
56:55 conscious, our brains are active, off most of the motor activity,
56:59 during R. E. M. , you have activity and motion of
57:03 eyeballs. Some of it is You know there is no clear cut
57:07 . Use 25% only it changes and changes it shifts and it shifts based
57:14 the tasks. So as you're looking this map, I'm gonna bring this
57:19 up to you. Can you imagine map of the brain For a cell
57:27 50 years ago. five Oh that have been 1980 72. There were
57:37 cell phones. So do you think was a map and neuronal activity dedicated
57:45 processing activity from cell phones? No was a map that was dedicated to
57:53 phones and pay phones and 1 880 collect colony. Okay, There was
58:01 different map why? Because there were cell phones. And when the first
58:07 phones came out I should bring you first cell phone I just found in
58:10 drawer. I couldn't believe it I think it's a Samsung. I
58:15 watching some commercial on tv said bring any year or anything something Samsung to
58:22 for a new one, go to and pull out this old thing that
58:26 have to pull out an antenna. Samsung. I was like wow,
58:31 know, it's worth something but I'm on to it, I don't need
58:36 new phone now. But so the of the matter is that it's not
58:41 that technology allows us to visualize it's also technology influences our brain activity
58:47 brain maps of brain plasticity and can that plasticity from the pay phone
58:53 Walking, styling, talking and walking to six hours of this. No
59:05 maybe sometimes no talking okay, it's here, there's a map in
59:13 so we have to make sure it's . Okay? And the reason why
59:19 have these maps and we have rearrangement plastic rearrangements and when we talk about
59:23 other sensory system I'll show you examples an experiment with the monkey activating two
59:29 repeatedly and what happens to the brain responsible for those two fingers. This
59:34 areas responsible for two fingers become very and the brain areas processing information from
59:39 other three fingers become very small, . This is just what we're going
59:45 actually. Evolutionary technology advancement. So these brain maps be changed?
59:53 We know that imaging techniques that FmR show the brain and action confirm that
59:59 functions are carried out in specific areas the brain. Each function is observed
60:04 more than one neural pathway. So use the example of the speech understanding
60:09 speaking speech Now this redundancy. So you damage something you still have partial
60:16 because it's not all in the same . When one pathway is damaged,
60:20 may compensate. Making this localization harder see. Other pathways may compensate if
60:27 redundant pathways processing the same information or senses may take over the areas of
60:32 brain that have been damaged emotions as learn. Character traits are also
60:38 You can actually call up on people's through micro stimulation of certain area.
60:44 have a certain sitting person sitting there you micro stimulate their emotion area and
60:48 start screaming, you evoke that emotion seat for that emotion. And um
60:56 lobe epilepsy which is a very common of epilepsy if it involves the temporal
61:00 can also have these emotional components that not necessarily uh tonic clonic, what
61:07 call the jerks and the stiffening of muscles. But it may have an
61:14 component, seizure, maybe somebody screaming somebody and just going berserk and then
61:22 and not remembering what happened because it's emotional centers and involved in emotional memory
61:29 potentially impaired for that person. Everything matter these days. Everything is
61:38 What I mean by matter is you know, we're drawn to our
61:43 versus the person across the table We're thinking that, you know,
61:48 rather hang out with Kardashians on the than my friends because I don't know
61:55 . But um so this is this becoming like every day and if you
62:01 again 50 years ago, virtual have you tried it? And so
62:07 look at this brain map here and is the display that was placed at
62:12 Contemporary Art Center in Houston. It's Contemporary Art Center. It's not no
62:17 that this was years ago. Contemporary Center is free because you need to
62:21 it. It's great. It has exhibits this whole uh museum center,
62:30 History Museum, I believe Thursdays after PM is free. Maybe some of
62:36 things we talked about neuroscience, you discover their, if you're into
62:40 you know, the new kinder building been built. The Museum of Fine
62:45 , Thursdays is also free day thursday contemporary art centers is always free or
62:51 can do a $5 donation. But you don't, nobody's gonna look bad
62:54 you. And this is where I this exhibit and this exhibit was that
62:59 sat at the table in front of computer and you were looking at the
63:04 dimensional screen and there were these snowmen my task was to click a snowball
63:12 as they click the snowball, I them to Snowman and the snow man
63:17 would explode. It's like kind of really almost like very slow meditative game
63:22 you're pressing on that and watching these go away and then you submerge yourself
63:28 the virtual reality versus a two dimensional and their environment is a lot more
63:34 and very different. This illustrates the task that is being performed with no
63:42 reality versus with virtual reality. And can see that this brain math is
63:50 . I'm not saying that virtual reality our brain math smaller. It's different
63:56 configuration and activity flows. So virtual and all of the things that will
64:01 experiencing will also influence us. I somebody had a question but I also
64:06 I'm running out of time alone. I'll ask you to spare that question
64:10 I'm seeing that I'm also not going be able to get to the covid
64:14 today so I'm not gonna push We'll come back and talk about that
64:17 necks lecture. I'd like to just by telling you there are many disciplines
64:22 neuroscience. You can benefit from You can think of the future in
64:27 careers of neuroscience for example neurologists, of the nervous system. M.
64:33 . Psychiatrist MD neurosurgeon. Somebody that's cut your brain neurosurgeon will work with
64:39 neurophysiologist as a neurophysiologist. You can in the operating room explaining to a
64:45 maybe why you think this part of brain is more important than the other
64:49 on the electrophysiology test. If you're during the surgery before the surgery,
64:55 pathologist and most of the pathology labs run by ph D. S.
64:59 actually lives big centers inside the hospitals by phds don't think that there's no
65:05 Medical School of PhD and you can many different careers. I'm a
65:12 very much interested in neuro pharmacology, devices, novel ingredients, nature derived
65:20 that can be applied for medicinal and uses a vast experience with neural anatomy
65:26 some with molecular and computational neuroscience as and like I said you can look
65:32 this yourself but the point here is if your occupational therapy, speech
65:36 drug rehabilitation, computer science, you benefit hugely from the basic tenants of
65:42 that you're gonna learn this semester. so I'm gonna leave it here and
65:47 for now, getting to cope with team and exciting about it again,
65:51 will do so on Tuesday, enjoy weekend. I'll see you on
65:54 Those that have questions. Please save if this lecture related for next lecture
66:00 ask me now. Thank you all zoom. See you
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