Here is a, Study about this structure. The dendrite and the dendrite synapse. So this is a cranial cell right? This is a mitral cell. They also have the dendrite and a dendrite synapse. Take a look here. This is a cranial cell, this structure and the then this is a mitral cell. I guess actually you don't mention the synapse to you. Can you recognize where is the granule cell presynaptic region, and the four mitral cells corresponding in the post synaptic region? For a presynaptic region, you need what kind of thing? >> Vesicles. >> You need a lot of vesicle right? Indeed, you see here, a lot of vesicle here. And actually, this is actually corresponding to a presynaptic region for the granule cell. And then this is a post synaptic region for the mitral cell. And then from granule cell to the mitral cell. Many use what, GABA right is a feedback signal. And then from mitral cell, you also have, you see here, a lot of this kind of vesicle, okay? And then this is a cranial cell receive the information from mitral cell. And then this cell, cranial cell will feed it back to the mitral cell. How this cell release neurotransmitter? If you use that dendrite to form a synapse we talk about actually neurotransmitter this you need action potential coming down to the axon terminal, and then you need the calcium channel. Once you get the calcium channel activated and the calcium going in and trigger the vesicle fusion, right? And it sends the release, but in this region, how can you trigger the neurotransmitter release? [FOREIGN] >> [INAUDIBLE] >> Okay. Calcium independently released right? So what kind of process in the calcium independent of release? >> [INAUDIBLE] >> [FOREIGN] >> [INAUDIBLE] >> Okay. This is a quite interesting topic, right? So, how these cells can release the neurotransmitter from the dendrite. So, it's a recording. So, if you want to study this this process. Actually it's quite challenging. You cannot do the patch for example. Just from a patch can recording from this kind of dendrite membrane. So, you then have some special way for this study. As I mentioned, this guy somehow you see this is endocrine cell. They release the neurotransmitter from the dendrite. From that study, people found actually the endocrine cell express those empire receptor. For example, the receiver with the glutamate stimulation from the bipolar cell. And then those empire receptor take in less calcium go in, okay? And it's those calcium from the empire receptor, and it trigger the release, okay? And the olfactory system I guess may be similar mechanism can be responsible for the neurotransmitter release. And so we mentioned that at the first lectures about this chemo reception we talked about actually the olfaction is very profound, has profound effect on a human being, right? That's actually for the, sometimes the long term memory and also sometimes for the emotion. Let's take a look how the olfactory information propagate in the brain. So this is the olfactory epithelium. This in our notes, okay? And then the information will propagate to the olfactory bulb. Olfactory bulb, and then is mainly used those glumernis right [FOREIGN] okay. And the information will process from the olfactory bulb and this olfactory system is really unique. In most the sensory system that information actually before going to the cortex, you'll need relate by the sentiments. [FOREIGN] the sentiments okay? But this guy, actually does not relate by the [FOREIGN] sentiments. Directly from this olfactory bulb, packaged with the olfactory cortex. It has is red direct. [FOREIGN] Let's take a look what kind of region to target row in. For example from this olfactory bulb they can target the TC information. Sending the information to this region. This region of cortex then is like a [FOREIGN], mainly for the emotion okay. [FOREIGN] that you'll feel, [FOREIGN] and also this information can directly go to this region, pure form cortex and [FOREIGN], okay? And also project to this region, redirect. So the cortex, again, it stores the information from the nodes. It's really direct, only about two synapse away. One synapse here and then another synapse here. In the visual system, you need to go to photo receptor to bipolar cell one, bipolar to ganglion cell one, ganglion cell to LGN one. LGN then go to the brain, the delay of four. And then you need a fourth synapse. Okay. So let's take a further look at the information processing or representation of this effect or signal. Okay. So we mentioned the the olfactory information. In the olfactory epithelium is distributed right? And then you go to the brain, the olfactory bulb, then you have, really, the map there. It's really discreet. [FOREIGN] Okay how about in the cortex? So for this coding, for your information coding, it looks actually, it's quite simple right now. For the decoding, because your information already code into these individual map cells right? So for a brain, like for us, we just need to take microscope, open this area. I don't need to know, actually, what kind of chemical you are using. I just need to read how many these what kind of pattern of this glomerulus activated then I would know. Which chemical you're using, right? But the problem is actually, in the brain there was a no microscope, and for this guy, for this brain cortex to decode this information, then need to use this neuro receptor. So how this map represented in this cortex region? That's really an important questions in the field. People try to understand the system, right? What kind of strategy will you use to study this problem? The question is how this map information from the olfactory bulb is represented in this cortex. It's in the map there or actually something what happened differently. So, to study this question. What kind of strategy will you use?