| 00:00 | So this is the final exam or midterm three Neuroscience exam review session, |
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| 00:07 | we will go over some of the material that we covered and they'll slashed |
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| 00:12 | section off the course, and we with the visual system. And if |
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| 00:17 | recall, you had information off light enters into the retina, we studied |
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| 00:25 | retinal circuit and then the outputs from retina coming into the lateral Jean Nicolet |
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| 00:31 | of the thalamus from lateral Jean nucleus of the columns that information traveled |
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| 00:36 | the primary visual cortex V one. subsequently there were two pathways that split |
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| 00:42 | the dorsal parietal pathway and into the or ventral inferior temporal pathway here. |
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| 00:49 | we understood the anatomy off the off the lot of genetic alert nucleus |
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| 00:55 | the primary visual cortex. And we the neocortex. Anatomy of the primary |
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| 01:01 | neocortex is sort of, ah, for the canonical secretary that you will |
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| 01:09 | New York cortex and many different parts the cortex. Thio, please recall |
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| 01:15 | the anatomy of the eye. When light enters, you have the highest |
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| 01:20 | vision here in phobia, but you the specific anatomy of the eye that |
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| 01:26 | the light through the pupil into the areas of the retina, which is |
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| 01:32 | in the very back of the And as the light enters into the |
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| 01:39 | , encounters retinal circuit. It bypasses all of these cells and the photo |
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| 01:47 | that convert the signal of light into electrochemical signal. These photo receptors are |
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| 01:54 | in the very back off the There's cone and rod for the receptors |
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| 01:59 | are connected to bipolar cells and retinal . South retinal ganglion cell accents them |
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| 02:06 | the fibers off cranial nerve to or nerve and exit out of the |
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| 02:14 | Traveling into the lateral Jean Nicolet as well as some other structures that |
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| 02:21 | retinal input. This synaptic transmission processing this information is also modulated further by |
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| 02:30 | horizontal on a McCain cells is shown . The two important things this photo |
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| 02:40 | air the only light sensitive cells and ganglion cells is the only output that |
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| 02:45 | out off the retina, so the cells will produce the action potentials in |
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| 02:52 | optic nerve and communicate that information. , the thalamus and columnist, will |
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| 03:00 | that information to the core attacks. air the layers of the retinal ganglion |
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| 03:04 | a plex reform in a nuclear outer to form out of nuclear layer photo |
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| 03:09 | outta segments and pigmented at the This is a very back augmented epithelium |
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| 03:15 | the photo receptor out of segments. this is the exit point here where |
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| 03:20 | ganglion cells will actually project the optic output. Here we have different |
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| 03:29 | rod and cone photoreceptors who please review anatomy. The fact that the Rod |
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| 03:35 | have free floating disks and we distinguish rod photoreceptors and mostly night responsible for |
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| 03:43 | vision and our acrobatic and have low acuity. And it is a slowly |
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| 03:50 | system as opposed to the cones, low sensitivity. But they also process |
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| 03:57 | acuity, vision and color. But need direct access oil rays of light |
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| 04:03 | direct rays of light illuminating something penetrating your eye in order to perceive all |
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| 04:10 | these details and so in the phobia will have the highest concentration of cones |
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| 04:16 | rods will be dominating in the But the blind spot illustrated here is |
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| 04:22 | an exit side for all of the ganglion cell fibers exiting out of the |
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| 04:28 | . This is another representation of the zone where you have this, |
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| 04:33 | indentation here and the actual structure allowing the light to most directly contact the |
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| 04:39 | cells that are located in the center the phobia. The three cone receptors |
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| 04:45 | blue, green and red, uh, they are optimally activated by |
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| 04:52 | light or green light. What we as green light and the combinations off |
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| 04:59 | colors come from a very degree of of these three different types of cones |
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| 05:06 | you can imagine you have color mixing on. And it is really the |
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| 05:12 | color information that is out there between 100 nanometers of wavelength that we can |
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| 05:20 | we can perceive. Photo transaction happens the retina. It happens when you're |
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| 05:32 | , typically with activities you protein coupled and other systems. But in the |
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| 05:37 | transaction and with light, it's the that activates a G protein coupled receptor |
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| 05:44 | the effect of enzymes and the mechanism that in the dark, photo receptor |
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| 05:52 | are deep polarized because there's ample amount cycling GMP which keeps the sodium channel |
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| 05:59 | and in the light that cycling GMP converted into GMP and you actually have |
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| 06:07 | high propeller ization. So this is opposite to what we studied excitation in |
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| 06:13 | way, in the eye excitation excited put off. Visual stimulus means hyper |
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| 06:19 | off the photo receptors. And so have written all that gets activated by |
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| 06:26 | light and activation of G protein coupled converts through Fox for the estimated cycling |
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| 06:34 | into GMP. And in the absence cyclic GMP, the sodium channels are |
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| 06:39 | . And because there is a decrease sodium or positive current influx, you |
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| 06:47 | hyper polarization. We also described receptive properties, and the most important take |
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| 06:53 | message is, is that you have and collections off receptors, photo receptors |
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| 06:59 | the retina, the process information in visual field and they're receptive. Field |
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| 07:07 | of these concentric on and off, center, off surround or off center |
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| 07:13 | on surround receptive field properties, and receptive field properties are created by thes |
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| 07:21 | of photo receptors that are communicating that to buy all themselves on further down |
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| 07:28 | the retinal ganglion cells. The take message from this diagram that if you |
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| 07:35 | on center Sal, the maximal stimulation receptive field would be if the stimulus |
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| 07:41 | the outside world was focused on a small piece of retina, very small |
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| 07:47 | of right now that contain these on receptor cells. And it will generate |
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| 07:51 | of the action potentials when only the of that receptive field that collection off |
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| 07:55 | photo receptors was activated and in the situation is to surround off center ganglion |
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| 08:03 | is the most actual potential. Start the surround of the cell of these |
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| 08:08 | field properties of these cells is We discussed that there's a circuit that |
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| 08:17 | for the cells to be either signed or sign inverting for the cell synopsis |
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| 08:26 | exists between the photo receptors and the cells. Most important thing is that |
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| 08:31 | sand concerning synapses are found in the cells that have kind of a kind |
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| 08:37 | interceptors, and that simply means that there is deep, polarizing glue domain |
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| 08:41 | is released by these photo receptors, does glutamate is released as glutamate? |
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| 08:47 | means excitation in the south means the wonders. Deep polarization of glutamate is |
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| 08:53 | . It's also going to dip. this cell from the sign conserving synapse |
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| 08:59 | it has an umpire kind of On the other hand, some other |
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| 09:04 | cells have medical, tropical, intimate and glutamate and excitation, and the |
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| 09:11 | release of glutamate actually inhibits activity of cells. But this diagram specifically shows |
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| 09:17 | center in Europe and the light, what happens in delight is the cells |
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| 09:21 | proposal arise. And so if this hyper polarized, there is not enough |
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| 09:26 | . And if it's a sign conserving and this off center bipolar cells hyper |
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| 09:31 | on this off center ganglion cell is hyper polarized. Now, if you |
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| 09:37 | the light and the sellers hyper it means you cut off glutamate. |
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| 09:40 | cell, on the other hand, glutamate is inhibitory because of the |
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| 09:45 | This on center bipolar cell is actually polarized. And then you have some |
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| 09:50 | synapses here because all of the retinal cells will have complicated and MBA synapses |
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| 09:56 | therefore hyper polarization. Hyper polarization. , uh, hyper polarization here means |
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| 10:03 | polarization and inverted deep polarization and deep here means deep polarization of his gang |
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| 10:09 | self. So as long as you the concept of all often signed conserving |
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| 10:14 | Simon averting synopsis and the fact that sign inverting synapses have bipolar cells and |
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| 10:20 | notable tropical and made receptors, you're to be fine and answering all of |
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| 10:25 | questions or identifying any of the details only ask of you are in the |
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| 10:31 | questions. During this exam. The home message of this was that the |
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| 10:35 | salsa actually inhibitory synapses, so the conserving synapses between photo receptor on the |
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| 10:43 | cell. So when the photoreceptors deep , the horizontal cell is deep |
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| 10:49 | but the horizontal cell is in turn these photo receptors. Okay, So |
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| 10:57 | this horizontal cell is deep polarized and becomes a sign inverting synapse because deep |
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| 11:02 | of horizontal sell means release of gamma transmit onto the photoreceptors and that means |
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| 11:09 | polarization of the photoreceptors. Mhm. again you have horizontal cells that have |
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| 11:19 | . They are very well connected through junctions, bipolar cells, cones that |
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| 11:24 | glutamate, and then you have horizontal that allow also for broad area retinal |
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| 11:33 | . It kind of a sharing of information across different receptive fields off the |
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| 11:41 | . So now we're moving into the processing of the visual information and we |
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| 11:49 | that there is PNM cells are coming of the retina, and we also |
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| 11:53 | that there is non MP type cells the projections from the retina. In |
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| 12:00 | 80 to 90% go thio, L m 10% go to superior curricula |
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| 12:06 | And the fraction of 1 to 3% to super charismatic nucleus, which is |
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| 12:10 | charge of the circadian rhythms. The from each I cross have a component |
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| 12:18 | crosses over and has a component that on the same side. Thio, |
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| 12:23 | that if you injure this area here the chi as um, it gives |
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| 12:29 | a tunnel vision and one of the exams. There's a question about Goliath |
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| 12:35 | Goliath was thought to have had um, tunnel vision. And it |
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| 12:43 | quite, um, often occurring in giants because the sky, as |
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| 12:52 | is located close to the pituitary So engorged pituitary gland would be putting |
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| 12:57 | on the chi Azman, causing overtime tunnel like vision and pituitary lines are |
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| 13:03 | in. People that are very large very large growth hormonal growth, |
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| 13:12 | growth and are sometimes dubbed this giants . Nikolic Nucleus is a six slash |
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| 13:21 | . You have to magna lairson for . You have parallel processing because you |
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| 13:28 | redundancy. And how many layers of information from one eye each one of |
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| 13:33 | layers is processing information from just And I said, Chairman ocular, |
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| 13:38 | empty field properties in the algae on very similar thio all on offer something |
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| 13:43 | property. So we just discussed in retina and l g m receives 80% |
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| 13:50 | its input from cortex retina sense most its output to the l. G |
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| 13:56 | . But L G M receives most its input from cortex so concerned not |
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| 14:02 | with processing the primary visual information, all of the cognitive cortical information that |
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| 14:09 | communicated back into this major sensory Eso please review the anatomy of the |
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| 14:18 | and recall that eventually to each we have not as dense collections of |
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| 14:25 | and these cells are thought to be your cellular or non MP or |
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| 14:30 | Intra Lonmin ourselves. Um, the 17, as is shown here around |
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| 14:36 | cultural and Fisher and occipital lobe Primary cortical area, is quite small compared |
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| 14:44 | macaque monkeys, where the primary visual area again. How much of the |
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| 14:48 | is dedicated to primary information processing rather cognitive processes? Higher processes that surround |
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| 14:57 | visual information? We have read no map, and so you have a |
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| 15:01 | by point representation in the retina that concerned GM along the way to the |
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| 15:08 | Cortex cortex has six layers, and six layers is in the way. |
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| 15:16 | anatomically segregated from each other, dividing labor into certain aspects responsible for certain |
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| 15:25 | . The strike a appear in, , that's referred. Thio Stride |
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| 15:32 | The primary visual cortex, is referred as a strike cortex because if you |
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| 15:38 | injections and one eye, you will those projections from one I lighting up |
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| 15:44 | stride in Layer four off the primary cortex. So these are stride that |
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| 15:54 | information cortical information processing from one or other. I also referred to as |
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| 16:01 | dominance columns so that the Layer four South is Stillman ocular, but one |
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| 16:07 | information gets projected. Them thio more layers to three. Their information already |
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| 16:14 | binocular. So if you recall you the jalonick inputs, mostly innovating. |
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| 16:21 | the non NPR intermediary pathways bypassing. , going into learn to three. |
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| 16:27 | is still, um a cortical inputs cortical lee that information long distances gets |
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| 16:33 | through lateral excite interconnections and layers to goes toe other extra stride cortical areas |
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| 16:39 | receives information from other extra stride cortical . That information not only gets spread |
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| 16:47 | the cortical there 23 longer distances, also gets communicated back in what we |
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| 16:53 | this filter cortical loop into layers 56 deep layers will actually contact back into |
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| 17:02 | Solomon. So they're six projections will into the l G m. So |
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| 17:06 | air called cortical thalamic projections and intra lee. That information is also going |
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| 17:12 | be communicated onto layer four and therefore have a Philomel cortical input coming in |
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| 17:19 | have a intra cortical loop 4 to lateral connections. 235642356423 This is an |
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| 17:30 | cortical loop and finally have the cortical information that is going out of the |
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| 17:36 | going into the sub cortical areas, as the visual follow most, a |
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| 17:40 | of ridiculous nuclear's. These are the circus that we discussed the llama cortical |
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| 17:46 | of cortical thalamic circuits that can engage areas of the cortex that can spread |
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| 17:52 | between sensory cortical areas, but that can get hijacked by neurological dysfunctions and |
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| 18:01 | disorders. Reinforcing the negative information or signaling. The south and the cortex |
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| 18:11 | , um, combinations of what you see in the retina and the |
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| 18:16 | G M. And so if you at the receptive field properties of the |
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| 18:20 | visual cortical south to represent the convergent from these more simple concentric on and |
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| 18:28 | luminescence processing that's coming from the retina the L. G. M, |
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| 18:34 | you have the cells that are sensitive orientation, you have the south of |
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| 18:39 | sensitive thio direction, and you have fuel properties that are quite diverse in |
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| 18:46 | shapes and representations, whereby these receptive of the layer off the simple and |
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| 18:52 | like South and the primary visual always to create what we call the |
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| 18:58 | sketch. The Quantrill, Alliance, , color and the fusion of the |
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| 19:04 | information off the outside world that we the secondary tasks. Tertiary on Mawr |
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| 19:12 | visual information processing will be performed in two, d three d four. |
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| 19:18 | finally we blended with information and association . This is again the remind there |
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| 19:23 | you have orientation columns where in these columns these and Michael columns you'll have |
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| 19:29 | that live next to each other with columns. So you have both column |
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| 19:33 | laminar anatomy and the cortex of South live next to each other in these |
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| 19:39 | process similar type of orientation and the stimulus that's coming from the outside |
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| 19:45 | So you have pinwheel like structure where cells in the middle will be |
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| 19:49 | processing information from different orientations. And more you go to the edge of |
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| 19:54 | micro column, the more specific are to. The cells were going to |
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| 19:59 | reacting Thio bar of light in a orientation, and these experiments, where |
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| 20:09 | and performed using well, the sensitive and later in explain to you how |
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| 20:15 | happens. So you have the orientation that form within the ocular dominance |
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| 20:23 | And you also have these blobs that responsible for increased metabolic and information |
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| 20:30 | associate ID with color information processing. for the optical imaging, we discussed |
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| 20:38 | sensitive dye imaging, which we did on. But an important, um |
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| 20:44 | matter that we discussed here was this that is shown here. And we |
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| 20:51 | about how a short term deprivation on sensory input in this case of the |
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| 20:56 | input with the future of an not even injury to the eyeball or |
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| 21:01 | to the nerves or anything, simply the animal of the sensory input during |
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| 21:07 | critical period of development. This is critical period of development for visual information |
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| 21:13 | rodents is the first month to two of life, and what happens in |
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| 21:18 | first two months of life will determine term with the connectivity. And the |
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| 21:24 | is between these cortical networks. And experiment showed that if you deprive animal |
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| 21:31 | three days, you can still have significant input from the from from the |
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| 21:37 | I but the deprived I even after short term, three or six |
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| 21:42 | the deprived I the inputs coming from following us into the cortex are going |
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| 21:46 | be reduced. Their number of the . There's gonna be attrition off the |
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| 21:55 | and snap the contacts in that area now dominated by the hips collateralize. |
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| 22:01 | the projections from the bilateral I, one that remained open will dominate. |
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| 22:07 | effect can be re, um, back to normalcy the ocular dominance columns |
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| 22:15 | the deprivation is short. But if deprivation is long for six days during |
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| 22:20 | first month of development, you can long term off potentially persistent changes and |
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| 22:27 | anatomy of the cortex and the And how much information will be paid |
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| 22:32 | to by the cortex if you once that I reopens again. And |
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| 22:37 | that theme off plasticity, that theme changing circuits and that theme off one |
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| 22:45 | area map taking over the other cortical continued throughout our conversations in this |
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| 22:53 | Now we're moving into the hearing just sound just sound molecules coming in 343 |
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| 23:04 | per second traveling through the air and air the compressions and rear factions of |
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| 23:08 | molecules, the compressed air molecules that oscillating in there for the oscillation of |
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| 23:15 | speaker can reproduce the compressed air and thes sound waves that are traveling through |
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| 23:21 | air. Low frequency versus high We just discussed low intensity versus high |
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| 23:27 | , so it can be the same . But it could be much |
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| 23:30 | or the tone can change from low , too high pitched tone. Our |
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| 23:35 | audible range is 20 to 20,000. in the air. We have this |
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| 23:41 | anatomy, so don't stick a curative into your external auditory me. Eight |
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| 23:48 | because you may, punk tree, a panic membrane or produce unnecessary stress |
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| 23:54 | in your obstacles. That's right. have the outer air opinion in the |
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| 24:00 | canal, going into the air the middle air air drum connected to |
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| 24:04 | obstacles and the inner air, which connected to the cochlea through the oval |
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| 24:10 | on the obstacles. And Coakley is part of this tubular cochlear Peratis, |
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| 24:16 | the cochlear portion of the cranial under , which is Mr Bill cochlear or |
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| 24:21 | . The stimulant nerve have the institution here, which is the going into |
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| 24:27 | and is responsible for oppression. Normalization the air and in the oral |
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| 24:32 | The three obstacles some value sinkers and E's then amplify the vibrations off the |
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| 24:39 | , Graham and move on to this played off the oval window and the |
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| 24:45 | of the oval windows. That's off movement of the fluid and the movement |
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| 24:50 | the fluid and the three shamers through , the stimulus scholar, media scholar |
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| 24:56 | . The Scholar Media is the one contains the organ of Corti, and |
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| 25:01 | you were unrolled this cochlear, which about the size of the P, |
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| 25:06 | would see a particular structure and the Leah. And in the three chambers |
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| 25:13 | the top chamber of the stimulus on bottom, timpani Paralympic is very similar |
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| 25:18 | a super spinal fluid that we Another new neurons and end on land |
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| 25:23 | unusual because it is very high in concentration that is created through the active |
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| 25:29 | through ST uh, vascular Aris and organ of Corti, where the hair |
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| 25:35 | are located there. Basil and pictorial are located in this end of the |
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| 25:40 | environment in the scallop media, just in the retina, you had written |
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| 25:46 | topic map point by point representation, have the Tono topic. Map This |
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| 25:51 | a topic map indicates that the highest sounds process the closest to the oval |
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| 25:58 | and the lowest frequency sound this process hear the apex, also called hilly |
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| 26:04 | off the cochlea. This tone a map is preserved all the way into |
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| 26:09 | cortex, and information is included that the fluid movement to set off in |
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| 26:15 | Paralympic around these two chambers, the of the basilar membrane will display Sicilia |
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| 26:23 | the direction of the cilia with regard the tutorial, membrane and displacement. |
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| 26:28 | of bending of the silly into the will cause deep polarization on the bending |
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| 26:33 | the cilia into the left, and downward will be responsible for hyper |
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| 26:40 | so the same time of so it'll . Waves now become mechanical sound |
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| 26:48 | The sound fluid waves move the membranes the Sinus oId fluid waves in code |
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| 26:59 | of Sinus oId electrical activity in these cells that send receptor potentials, these |
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| 27:06 | potentials air heard by the spiral ganglion that comprise the auditory nerve portion of |
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| 27:13 | CBO, cochlear nerve and the spiral cells. Their accents are connected to |
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| 27:19 | in her hair cells. Wonder of hairstyles and three rows of the outer |
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| 27:23 | cells. These are McCann a, , transducers. These channels are mechanically |
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| 27:31 | channels. So in the retina we optically gated channels and these channels, |
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| 27:39 | were opened by light. And these and the auditory system opened with movements |
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| 27:45 | their mechanically gated channels. And the of the silly and movement of the |
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| 27:50 | will open their potassium channels. Remember end. A limp is very rich |
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| 27:55 | the in the potassium, and the of the potassium will happen here in |
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| 28:01 | indolent that will cause deep polarization and of calcium. This is the parallel |
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| 28:07 | . Influx of calcium and the release the excited during neurotransmitters generating the receptor |
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| 28:14 | . These receptor cells, hair cells the mechanical movement of the fluid into |
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| 28:22 | polarization and neurotransmitter massacre. Ruiz. of the information that comes out of |
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| 28:28 | retina off the cochlea comes from the hair cell. So you have most |
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| 28:34 | the connections from spiral ganglion cells contracting her hair cells and, uh, |
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| 28:40 | outer hair cells. There's a homework here. What is the equilibrium potential |
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| 28:45 | in the hair cells? Do you that? What is equilibrium potential? |
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| 28:49 | ion Haddon Ernst Equation calculating its own potential and that equilibrium potential waas our |
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| 29:02 | . It has some very interesting things dependent on the concentration on the house |
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| 29:07 | versus the inside and the RTZ F . And now what? You have |
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| 29:12 | of very high concentration of the potassium the end, a limp. So |
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| 29:17 | liberal potential for these cells will be because destined concentration is very high on |
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| 29:24 | outside as opposed to when we did original nurse equation calculations. And we |
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| 29:30 | that the sodium was very high on outside and potassium was very high on |
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| 29:35 | inside. And this is just the . So sound amplification happens in the |
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| 29:41 | hair cells. They have these very load of proteins and get compressed, |
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| 29:44 | they actually act like, sort of springs. And they amplifying the movement |
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| 29:49 | the pictorial membrane, allowing for the hair cell student code. More information |
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| 29:54 | then ultimately gets sent up, process the auditory pathway, and you have |
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| 30:00 | the spiraling ganglion cells, connections It's laterally to the ventral cochlear |
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| 30:05 | There they crossover contra laterally, a of them to the superior olive, |
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| 30:10 | at the level of the superior olive aural auditory information. Already they travel |
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| 30:16 | through lateral meniscus into the area off midbrain, where you have the inferior |
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| 30:22 | sauce in fair curricula. So essentially with processing some of the rudimentary auditory |
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| 30:30 | before it enters into the media lja nucleus of the thalamus and into the |
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| 30:35 | auditory cortex. They're still in a map. This frequency map in the |
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| 30:41 | world that activates on the certain South this Coke Liet organ of Corti is |
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| 30:50 | all the way through spiral gang themselves the cochlear nucleus and into the primary |
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| 30:56 | cortex. So this is not your auditory map, but this is the |
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| 31:00 | auditory map. But we have a auditory map, and we didn't really |
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| 31:06 | how that comes about. It's a bit more complex, so we talked |
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| 31:11 | sound localization, and if you we watched the very cool video about |
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| 31:16 | that showed how incredible they are. organization or one of the aspects that |
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| 31:21 | had this they had the syringe of that were surrounding the years. |
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| 31:27 | Imagine if you had two very large behind your ears helping your ears become |
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| 31:34 | in here better, and that is case with House. Plus, they |
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| 31:38 | a symmetry in the airs, which some great hunters at night. They |
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| 31:44 | great depth of sound maps as We talked about sound localization here and |
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| 31:51 | entrance off signal from one year will certain areas off superior olive earlier than |
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| 31:58 | signal that, after travels from left , will finally hit the right here |
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| 32:02 | activate action potentials from that side. , special interests. We're hearing impairments |
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| 32:09 | us, most of them. Hopefully conduction on some of them are sensory |
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| 32:16 | such as tinnitus, uh, loss hearing damage to hairstyles. It's all |
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| 32:23 | neural and in that case is off loss through hair cells. When there |
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| 32:29 | spiral ganglion cells still preserves. You have cochlear implants, so if you |
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| 32:33 | , you have a big implant that multiple electrodes, and these electrodes are |
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| 32:39 | matched to the frequencies of the spiral cells that would process specific frequency at |
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| 32:46 | specific length off the cochlear, corresponding its tone. A topic map. |
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| 32:55 | amount of sensors system overview. The processes pressure perception. Temperature came, |
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| 33:08 | , it's, ah, system that connected to the skin distributed throughout the |
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| 33:14 | and receptive fields distributed throughout the You have different types of receptors between |
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| 33:20 | and your puzzle opinion sendings. My score puzzles uh, hair follicle free |
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| 33:26 | here except the fields. This is point discrimination that showed us that receptive |
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| 33:34 | are much smaller for sensor information at level of the fingers and mouth and |
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| 33:42 | . But they're much larger in areas are not a sensitive thio two point |
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| 33:48 | or sensory discrimination such as casts or or torso. And we have some |
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| 33:53 | these, uh, receptive fields from score puzzles and petunia in core puzzles |
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| 34:03 | are rapidly adapting and Marco's discs of finis air slowly adapting. And then |
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| 34:09 | have some of them that have small , my business and Merkel's small Muslims |
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| 34:14 | , large Pechiney in Ruffini sendings. is important how you perceive and process |
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| 34:24 | sensor information that's coming on the The sensor information gets carried by four |
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| 34:29 | of fibers. The largest ones will off the appropriate exception. Second largest |
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| 34:36 | McKenna receptors of the skin, the and feeling density changes in the |
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| 34:42 | The third ones will process pain and , and the slowest wants that Aaron |
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| 34:47 | ated will be responsible for temperature, and itch. We have dermatologists in |
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| 34:53 | derma tone from the neck down processes from the skin region that is specifically |
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| 35:02 | to that one spinal segment on that side, uh, to that specific |
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| 35:08 | off the body. So Dermot owns the case of the shingles, will |
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| 35:13 | in one single dorsal root ganglion, , a consequence of reappearance of door |
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| 35:20 | herpes zoster virus, which causes these uncomfortable and painful itchy rashes and burning |
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| 35:29 | in just one single dermatology on one of the body. Information from the |
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| 35:37 | down, anything below the phase is through the spinal cord. It ascends |
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| 35:44 | the dorsal column nuclei through the dorsal that reaches dorsal column nuclei, which |
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| 35:51 | located here, OK, at the of the medulla, and that's what's |
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| 35:55 | matter. Sensor information crosses over Anything that gets damaged below medulla of |
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| 36:03 | Ghana is going to be on the side and anything that is damaged above |
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| 36:09 | going to be on the Contra lateral . If there's damage to the spinal |
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| 36:13 | , it may lack sensations on the side of the spinal cord. But |
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| 36:19 | there's a damage to the brain stem the billabong, gotta you. The |
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| 36:24 | is going to be on the contra side. From medulla, information goes |
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| 36:29 | eventual posturing. It was of the and from there to the primaries amount |
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| 36:34 | sensory cortex Information from the face is by trigeminal nerve. Five cranial |
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| 36:41 | Five large mechanical receptor accents innovating to principal trigeminal nucleus, which is located |
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| 36:49 | here at the level of the and it crosses over and penetrates |
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| 36:56 | The ventral pastoral nucleus of the columnist subsequently different area face area in the |
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| 37:03 | somatic sensory cortex. Eso We have map of the whole body and the |
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| 37:10 | sensory cortex. That's our homunculus. also have a map for digits and |
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| 37:14 | digit map. You have slowly and adapting neurons, and you have a |
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| 37:21 | map calling the layer map that represents digit in our brains is a lot |
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| 37:26 | information that gets dedicated to our hands fingers to our mouth. Lips here's |
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| 37:33 | here and our general areas, and a amount of sensory sensitive areas. |
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| 37:40 | this a matter talking that we see map representation is not continues Thio. |
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| 37:47 | you have generals. Next, two , uh, index finger next to |
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| 37:53 | , uh, for forebrain, forehead eso. It is a relation to |
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| 38:01 | body. It's more like a caricature the body and certain parts of the |
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| 38:06 | . Hands face are mawr important for ? War for appropriation. So matter |
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| 38:14 | rodents is very different than here. discussed the barrel cortex for each whisker |
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| 38:18 | whisker pad. Had representation of the like structure in the primary visual cortex |
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| 38:24 | sensory cortex, and that allows for lot of interesting experimental manipulations where you |
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| 38:30 | inhibit activity from one of the whiskers see how it effects the map. |
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| 38:34 | so we over viewed these different changes cortical maps, in this case with |
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| 38:41 | primary somatic sensory cortex of activation of two whisker and in this case with |
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| 38:49 | so you have a map for digits loss of one digit determines that the |
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| 38:56 | areas processing information from a day adjacent before the loss of digit three take |
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| 39:03 | that area. But the changes in cortical maps don't have to be a |
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| 39:10 | is lost off the finger or loss arm. It can be just through |
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| 39:17 | movement or repetitive stimulation of certain vicious certain parts of the body. And |
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| 39:22 | would see an increased amount of cortex space that is now dedicated to the |
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| 39:28 | digits on the hand versus inactive And if you recall, as it |
|
| 39:36 | , thio, these different maps brain . We watched a video by Hillary |
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| 39:46 | Ramachandran, and he described three very syndromes or conditions in that video and |
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| 39:56 | ways off solving or treating them. please remind yourselves off the Cobb grass |
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| 40:05 | or crabgrass delusion off the phantom limb or phantom limb delusion and off the |
|
| 40:17 | . Okay, so please review that by Hillary in Ramachandran, it's a |
|
| 40:22 | talk Onda, Please be prepared. , Answer some basic questions about what |
|
| 40:30 | conditions are. What are the parts the brain or the cord assists that |
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| 40:37 | involved in processing or are damaged in conditions. Mhm What we did. |
|
| 40:51 | also discussed a little bit in greater voltage sensitive dye image ing and uploaded |
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| 40:58 | for you. And the take home from this is to understand that there |
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| 41:03 | this vault excessive dies that can be in the membranes of the south and |
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| 41:08 | they will indicate the voltage change across membrane and that you can image large |
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| 41:14 | of the brain. You can do image ing. You have to have |
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| 41:18 | microscope in order. Thio image these windows of activity in the brain and |
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| 41:23 | can also experimentally correlated to activity that record electrically from a number of south |
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| 41:31 | from one individual cell. Andi, recall that there are different layers off |
|
| 41:40 | of studying the anatomy and functionality of brain. It goes from macroscopic |
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| 41:47 | Mesozoic, OPIC, different kinds of in the in the network to circuit |
|
| 41:54 | . How these cells are interconnected. cellular, where different channels located in |
|
| 42:00 | cells and what are different responsibilities off cells are different processes in the communications |
|
| 42:06 | celulas, a synaptic at the level been good experience and access ions. |
|
| 42:12 | so this illustrated also the article that uploaded, that these multiple sensitive dies |
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| 42:18 | also be genetically encoded, and in case, they become, not |
|
| 42:23 | But genetically encoded voltage indicators and this is very interesting. It discusses the |
|
| 42:32 | of these experimental techniques into practical And what is the future of these |
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| 42:39 | for very near future clinical application of of the disease or circuit dysfunction? |
|
| 42:47 | ultimately, what neurologists and neuroscientists want get at is understanding non invasively understanding |
|
| 42:56 | , a sub cellular level and understanding activity on a macroscopic level at the |
|
| 43:02 | time. That is the ultimate holy of nurse ons and neurology and non |
|
| 43:09 | image ing off networks of the Overall activity in the brain with ability |
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| 43:14 | zoom in on two single synapses, three trillion or many trillion of them |
|
| 43:20 | they exist. After discussing a little of vault of sensitive dye, we |
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| 43:27 | on to this very interesting topic and this is highly relevant and timely |
|
| 43:35 | in 19. How does go that enter into the C N s can |
|
| 43:40 | through nasal cavity. You can enter Valerie Mia blood virus in the blood |
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| 43:48 | reaches CNN s can enter due to damage where you have compromise of blood |
|
| 43:54 | barrier so you may have inflammation or response or virus in the blood. |
|
| 44:01 | that can affect the blood brain barrier allow for the virus to enter into |
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| 44:05 | brain. The easiest for the The interest through the nasal cavity. |
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| 44:09 | important take home message is here in nasal cavity will contain the nerve endings |
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| 44:14 | nerve endings of penetrate through these administrations the skull that I referred Thio ascribe |
|
| 44:21 | played formation and this crib reform play . You can see these actual ministrations |
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| 44:28 | the skull that physically allow for the of very small molecules. Infection in |
|
| 44:34 | nose were the virus and creeping up the virus to the crib. Reform |
|
| 44:40 | can in some instances allow that, , infection off the brain, covering |
|
| 44:46 | nose when breathing, not just your , but your announcement. Bringing this |
|
| 44:52 | and preventing not only accumulation of the and the nose or catching the virus |
|
| 44:57 | the nose and enter into the but also ex elation through the mouth |
|
| 45:04 | the nose. And I was out weekend again. I saw almost every |
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| 45:09 | person with her nose hanging out. I think I'm going to make a |
|
| 45:15 | , Uh, that I'm just gonna in front of people that says aural |
|
| 45:21 | . This is how the virus enters exits. Here's a picture. |
|
| 45:26 | you're not protecting yourself or others, be smart. Now, when the |
|
| 45:30 | enters, it has to hang on something hangs onto the H two receptors |
|
| 45:37 | these H two receptors angiotensin converting enzyme has involved in overall body home, |
|
| 45:43 | , Stasis, information and immune So basically hijacks. H two receptor |
|
| 45:50 | enters into the south and then the . N s. You have these |
|
| 45:54 | receptors that are located on neurons on as well as on the blood |
|
| 46:02 | the brain, the ferial lining that see here and this is where essentially |
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| 46:08 | have the potential for these viruses to on to is to penetrate itself into |
|
| 46:14 | ethereal self, causing more damage, more information, making the blood brain |
|
| 46:19 | loose, ineffective in infecting potentially glial of the blood brain barrier. And |
|
| 46:27 | it enters into interstitial spaces of infecting neuron Sa's well in the PNS versus |
|
| 46:35 | C. N s, once it into the peripheral nervous system, the |
|
| 46:40 | that the peripheral nervous system and main is a non announced me Andalusia eso |
|
| 46:48 | , off smell and loss of Um, that's because the hair like |
|
| 46:54 | on olfactory tissue, just like you hair cell receptors and the hair |
|
| 46:57 | You have these hair cell receptors, cell protrusions like back there tissue that |
|
| 47:03 | get damaged and die. So the major symptoms of gear on Bar Miller |
|
| 47:09 | syndrome And for the C. N . You have a headache and vertigo |
|
| 47:15 | main, sometimes with the major symptoms in both stroke meningitis, which is |
|
| 47:23 | officer, was spinal food, acute himself philosophy and bleeds, hemorrhaging, |
|
| 47:32 | of the brain, a Dema which swallowing, and with hemorrhaging. You |
|
| 47:38 | have hi coagulation stayed off these blood coagulating and thio into into solidified coagulates |
|
| 47:51 | the brain also binging on the normal of the brain. And this is |
|
| 47:57 | the left. You have mostly came sensory dysfunction in the PNS and then |
|
| 48:02 | C. N s. You have issues such as swelling, cerebral |
|
| 48:09 | compression of brain stem alteration and respiration of this acute necrotic. It's a |
|
| 48:17 | , the on bleeding hemorrhaging in the Onda. Of course, due to |
|
| 48:24 | stress, you can also have neural in the brain, which we discussed |
|
| 48:28 | neurons or some of the most sensitive to hypoxia, a lack of |
|
| 48:37 | So what can happen then? What happen? You have these things like |
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| 48:43 | blood, brain barrier swelling. You coagulation blood. Um, you have |
|
| 48:52 | , causes a Philip with him, so fill itis and cause lesions in |
|
| 48:56 | brain can lead to coma. ischemic stroke, which is lack of |
|
| 49:06 | . There's a hypoxic stroke where you off the blood supply. Systemic stroke |
|
| 49:10 | is when you have narrowing of the vessels because you have swelling in the |
|
| 49:18 | and there's too much pressure. There blood vessels and they bust open |
|
| 49:23 | causing stroke and blood, uh, in the brain that post infectious neurological |
|
| 49:32 | thio. And you can have also care related neurological manifestations. So the |
|
| 49:38 | home message from this is mostly that can have encephalopathies of Politis ischemic strokes |
|
| 49:43 | these other neurological complications and neurological manifestations intensive care related. You can also |
|
| 49:51 | in our articles review, but I not be asking you detailed questions from |
|
| 49:59 | . They're quickly in the last Novel Review The main take home messages |
|
| 50:03 | the contaminated system that you have major heaven do cannabinoids there synthesizing enzymes, |
|
| 50:11 | they're degrading enzymes. You have cannabinoid expressed widely throughout the body and the |
|
| 50:18 | and influence many different functions. But it seems to be involved in |
|
| 50:23 | You static and fast and slow you static regulation off the brain and |
|
| 50:28 | body in the brain. CB one that are responsible for the euphoric effect |
|
| 50:35 | very heavily expressed in hippocampus, basal , prefrontal cortex, cerebral cortex and |
|
| 50:42 | . But I will not ask you identify parts of the brain where these |
|
| 50:46 | receptors I express. It's more of general understanding that you see that it |
|
| 50:51 | widely distributed through the brain in different and binding off endo cannabinoids or fighter |
|
| 50:57 | to these receptors in different parts of brain can influence different brain functions or |
|
| 51:04 | dysfunctions. This is probably something that worthwhile reviewing. It's the same mechanism |
|
| 51:11 | we discussed again. We have the polarization Exocet, ASUs and on demand |
|
| 51:18 | of Under Cannabinoids that remembering soluble and retrograde fashionable bond to C B one |
|
| 51:23 | C B two receptors. CB one will reduce the influx of calcium and |
|
| 51:29 | transmission for both glutamate and GABA. we'll essentially in a negative feedback |
|
| 51:34 | will control excited during inhibitor neural And in addition in CB two |
|
| 51:42 | When this, uh, under cannabinoids two CB two receptors and Muglia, |
|
| 51:48 | will influence slower processes that are concerned the information from inflammatory Side of Crime |
|
| 51:55 | . Lawless some of the slower household on immune response of the brain that |
|
| 52:02 | mediated by CB two receptors. I this question whether it's actually many and |
|
| 52:09 | cannabinoid systems and the fact that under will bind to CB one CB two |
|
| 52:14 | . But they will also bind to receptors. Trevi receptors P part |
|
| 52:20 | They will influence iron channels. They're different body systems in different organs and |
|
| 52:28 | in this under economic system, and contaminated receptors or the contaminant molecules is |
|
| 52:34 | with distinct syndromes. Now I also questioned your understanding that the endogenous |
|
| 52:41 | such as under economic ones, combined other endogenous receptors such a certain elements |
|
| 52:46 | a strict view receptor. So there's lot of crosstalk between what we call |
|
| 52:51 | cannabinoid and serotonin system between serotonin system other systems in the brain and the |
|
| 52:58 | . This is an important lesson. low THC cannabis industrial home from high |
|
| 53:07 | cannabis, which is medical, recreational from synthetic marijuana sincerity, cannabinoids that |
|
| 53:15 | synthesized in the lab and made from again. You will not be responsible |
|
| 53:20 | answering these questions, but it's very that you know there's difference because Hampus |
|
| 53:24 | legal, you can grow it. researcher that there's products that are made |
|
| 53:30 | CBD that are regulated by state but federally legal. Then you have medical |
|
| 53:36 | recreational cannabis, which is becoming a part of the not only community in |
|
| 53:41 | , but medical community as well. these are the laws that are governed |
|
| 53:45 | each state, um, including State Texas synthetic and avenues. They're completely |
|
| 53:53 | , not regulated on, uh, deadly. Uh, we discuss this |
|
| 53:59 | cone, So please know the word cone, because these are the glandular |
|
| 54:04 | on many plants that will contain some the most important active ingredients. In |
|
| 54:09 | case of cannabinoids cannabis, try Combs contain cannabinoids and will contain other active |
|
| 54:16 | such as Turpin's, um, for medications. You have to realize that |
|
| 54:22 | have synthetic. Do you see since discovery in 1964 it was isolated from |
|
| 54:28 | plant material from hashish or hash in lab in Israel. And then in |
|
| 54:34 | eighties, we had synthetic THC medications were made and still available. And |
|
| 54:40 | in 2021st century saw the production of first plan based medications, such as |
|
| 54:46 | big small sir cannabidiol that are also different conditions for spasms and pain and |
|
| 54:53 | sclerosis. THC and CBD on for activity and Roddy Syndrome and childhood epilepsy |
|
| 55:02 | for the CBD preparation. Um, is an interesting take home message that |
|
| 55:09 | the plant cannabinoids are synthesized a specific . And if you have THC, |
|
| 55:15 | something's the plant will produce THC, CBD A something's the plant will produce |
|
| 55:21 | A and on Lee Heat and do elation will turn this non psychotropic, |
|
| 55:28 | intoxicating THC A into psychotropic THC. cannabinoids, all three of them, |
|
| 55:34 | be expressed by one plant and may a different relationship to CB one |
|
| 55:39 | So THC is an agonist. Activate one receptor C B G is an |
|
| 55:45 | CB one receptor, and CBD is negative al hysteric modulator. So that |
|
| 55:51 | it has a different binding site, it modulates the activity through the CB |
|
| 55:55 | receptor as it gets actively by In addition to cannabinoids and the |
|
| 56:01 | you also have Turpin's and Turpin's volatile volatile molecules on. They give very |
|
| 56:11 | smell, the cannabis plants and the plan. Preparations will contain a number |
|
| 56:17 | cannabinoids. We have over 120 different a number of Turpin's that would be |
|
| 56:22 | , but it all depends on processes which the plant is being processed, |
|
| 56:28 | on the products of being prepared. the take home message from this slide |
|
| 56:33 | not to memorize it, but thio what a complex interaction that is in |
|
| 56:38 | brain between the city cannabinoids, dicker dicker box related mutual cannabinoids, Europeans |
|
| 56:46 | the cannabinoids and the neurotransmitters major excited inhibit their neurotransmitters. And we basically |
|
| 56:53 | about how this CB one system is faster system. Regulating your transmission on |
|
| 56:58 | B two is a slower system regulating and some of the immune responses in |
|
| 57:04 | brain. And I refer to you . This National Academy of Sciences engineering |
|
| 57:10 | Medicine publication, which is publicly available the health effects of cannabis and |
|
| 57:15 | were in 2017. It was already that there is conclusive and substantial and |
|
| 57:21 | evidence for some cannabinoids in cannabis as medicinal blinds and medicinal preparations, and |
|
| 57:27 | is limited and inconclusive evidence for a of it. But in reality, |
|
| 57:32 | have millions of people that have and they're using cannabis, including |
|
| 57:37 | in many different ways, including here Texas, which has ah, compassionate |
|
| 57:42 | program, which is going to be over the next three years, providing |
|
| 57:48 | and jobs in Texas and creating what predicted to be over the next five |
|
| 57:54 | , or $3.2 billion economy in Texas , and we're just talking about medical |
|
| 58:02 | . High THC cannabis here. We're talking about low THC hom CBD, |
|
| 58:08 | is also a huge huge market So as you look into the |
|
| 58:13 | these air some of very interesting things be aware off golden 19 interactions in |
|
| 58:18 | brain and I think politically and biological , uh, renaissance of in the |
|
| 58:25 | system on medicinal cannabis |
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