Anatomical and functional connectomes underlying hierarchical visual processing in mouse visual system

Key Question Being Explored in This Insight:

Why is the claustrum considered one of the least understood structures in the mammalian nervous system despite its extensive connectivity and involvement in high-cognitive processes

View the page of: Răzvan Gămănuţ

Institution: Okinawa Institute of Science and Technology Graduate University

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Why is the claustrum considered one of the least understood structures in the mammalian nervous system despite its extensive connectivity and involvement in high-cognitive processes?

Image courtesy of interviewee. February 13, 2025

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This video video discusses the hierarchy of visual processing in the brain, particularly comparing mice and primates. It mentions the complexity of visual systems, the organization of neurons across different areas in the brain, and the presence of feedforward and feedback projections. The hierarchy is described with different levels of processing, but also acknowledges the complexity and nuance of these connections. While mice are studied extensively, they may not fully represent the advanced features seen in primate visual systems due to differences in brain structure and organization.

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1. The visual system in the brain needs to address the position of the self in space, the position of other objects in space with which the self will interact, and the speed of both the self and other objects during interactions.

2. Primates have the most advanced visual system compared to mice due to their ability to interact in complex ways, react cleverly to different situations, and process visual cues through dedicated neurons in the visual cortex.

3. The hierarchy of the visual system involves sequential processing of visual stimuli, with connections going from lower to higher brain regions. Neurons at higher levels of the hierarchy tend to respond later to visual stimuli.

4. While there are similarities in the visual systems of rodents and primates in terms of patterns of projections and receptive fields, there are key differences such as the density of connections and the depth of the hierarchy.

5. The visual system in mice, although complex, is not as sophisticated as in primates due to fewer connections and a shallower hierarchy. Studying the visual system in mice can provide valuable insights but may not fully represent the capabilities of more advanced visual systems.

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Here are the key quotes from the video you :

1. "The start of addressing this question is to clarify what a visual system needs to solve to address for the organism to which it belongs."

2. "The visual system in the brain needs to account for the position of the self in space and position of other objects in space to which the self will interact, and also for the speed of all the above."

3. "Primates have the most advanced visual system because they can interact in a complex way and react cleverly to different situations."

4. "The visual cortex of primates contains about 30 regions that respond to visual stimuli, covering more than half of the neocortex."

5. "Mice were not considered to have an ideal visual system, but in 2007, it was discovered that the visual system in mice is more complex than originally thought."

6. "Genetic tools used to study the brain in general and the visual system in particular are important because they target specific types of neurons."

7. "Mice are ideal for genetic studies due to their rapid reproduction rate."

8. "The visual system has an incredibly complex task to receive visual stimuli on two retinas and figure out the position of the self, other objects, and their movement."

9. "There are rules by which projections are done from lower hierarchical regions to higher hierarchical regions in the brain."

10. "There are similarities and differences in the visual systems of mice and primates, such as differences in the density of connections, hierarchy depth, and processing of visual features."

11. "The visual features in mice may be less sophisticated than in primates due to the shallow hierarchy and fewer connections."

12. "The processing of visual stimuli involves sequences but is more complex due to high-density projections and divergent pathways."

13. "The model of a strict hierarchy in the visual cortex must be nuanced to account for non-sequential processing of features."

14. "Although genetic tools allow complex studies in mice, the mouse brain is still less relevant than primate brains to understand advanced features of the visual system."

These quotes provide insight into the discussion about the visual system in mice and primates, highlighting their similarities and differences in processing visual stimuli.

X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:90000

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I think the, the start of,

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of addressing this question is to, to clarify

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what a visual system needs to, solve to, to, to address

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for the organism to which it belongs.

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So the, to put it very, very simply,

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the visual system in the, in, in the brain, it needs

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to account for the position of the self in, in space

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for the identity

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and position of other objects in, in space to which the,

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the self will, will interact,

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and also for the, the speed of, of all the, the above.

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So for the speed of the self

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and for the speed of, of the, the objects through which it,

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will interact.

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So, in this aspect, the, the primates are,

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are the, have the most advanced visual system

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because they, they can interact in a very complex,

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way to, with the world, around them.

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And they, can, react very,

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very cleverly to, different situations.

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And that may appear, during the, the lifetime.

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Uh, and this is, reflected in, the visual,

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cortex of, of the private, like the, the amount of,

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neurons that are, dedicated to, process

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visual, the, the, the vi

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the visual cues and, the visual information,

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but in the primate visual cortex contains, about 30,

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regions that respond to visual stimuli.

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And these regions, cover, more than half

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of the neuro cortex.

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And by comparison, the, the regions that respond

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to visual stimuli in mice, they, they were thought

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to be about four, so, up in the,

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until the late two thousands.

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And, it was known that they, they

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by about 15%, of, the,

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of the neocortex.

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So a much lower, lower proportion.

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And, for this reason, the mouse was not considered

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to be, to have an ideal visual, system to,

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to be a, an ideal model to study the,

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the, the visual system.

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So due to this, the small brain size

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and the low visual, visual activity,

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but, the, the breakthrough, here came,

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around 2007, when it, it was discovered

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that actually the visual system in mice is,

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much more complex that,

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originally had been, had been taught.

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And it actually, contains,

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some forms of, of the processing that, that,

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had been known from, from primate.

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These genetic tools, used to, to study the,

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the brain in general, and the visual system in,

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in particular are, are very important

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because they, the,

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they target specific types they like,

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they can target specific types of, of neurons.

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So, it is well known that the patterns

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of gene expression depend on the types of neurons

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and on the brain region, where, where these neurons are.

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What you do is what, once you, you identify a gene

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that it is possible to make the neurons expressing that gene

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to become fluorescent throughout their cell body

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accents and then drives.

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And, in this way, you can, visualize,

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the pattern of projections of these neurons

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or, you can, make the,

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the same neurons vary their,

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their fluorescence in direct proportion

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to their electrical activity.

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So then you can see to what stimuli from the,

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outside world, these neuro ones, respond.

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But in order to, get these, these genetics tools,

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one often needs several generations of, of animals.

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And mice are, ideal for, for this

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because, they have a first, a rapid,

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reproduction, rate.

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So, and, their gestation is about, three weeks.

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And then the, the time to need

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to reach maturity is about six weeks.

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So in, less than three months,

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you have about five function adult

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males from, from a female.

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And, by comparison, if you work with Maca,

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let's say from the moment of conception, you need to wait

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for, about three, four years to, to have,

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a functioning, adult maca.

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And, by,

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by using this, mice,

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you know, to have,

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by using mice in, in this, in this way, one could,

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could, could,

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it, it, yeah, it was a, a high,

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it was a basically a, an explosion of, studies

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that, that could, address, these,

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these incredible complex,

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it could this,

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Um, complex problems like, the patterns of projections

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and, the, the patterns of responses of, of,

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various types of neurons to, to define the,

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define visual stimuli, first, we need to define what,

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what the, what the hierarchy, means in, in this context.

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So, a hierarchy in, in the context

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of the visual visual processing means that once the stimulus

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enters, the, the retina, then, it,

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the information contained in, in the,

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in the visual stimulus is processed in, in steps.

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And, the, the later these,

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these, processing, this processing is done,

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the higher the region

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that does the processing is in, in the hierarchy.

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Um, a again, the,

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the visual system has this in incredibly complex task to,

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it receives, stimuli,

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vis visual ti stimuli, yeah, on, on two retinas.

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So basically two, two to the, images.

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And then it needs to figure out the, the position

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of the self, the position of other objects

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and the, the movement that, everybody has, in,

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in this landscape from these two to the, images.

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So, there, there are a lot of transformations

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to be done, and, these, these transformation, are,

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are done, sequentially.

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Um, so, there,

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there are two aspects of, of this hierarchy.

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Um, one can follow up the, the connections

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that go from the retina, along, to the thalamus

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and then to the, the brain

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and how, this, the, these connections are,

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are, are done through, throughout, throughout the brain.

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And then, one, one can do this,

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from the point of view of physiology

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and, see, record at what times, various,

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regions respond to, to visual stimuli.

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So for, for the structural, anatomy.

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So, following the pattern of

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the connections,

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it, it's, has been well documented,

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since about 50 years, ago,

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that there are rules in in which, by, by which the,

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the projections are, are, are done from,

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and lower hierarchical

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Region to a higher hierarchical region in, in the brain.

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So main, the, the cortex, now

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is, it's composed of the, of six layers,

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of the regions of the cortex are composed of,

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six layers.

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And, the rule is that, feedforward, projections,

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so, projections from a, a,

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a region that processes the stimulus at an early stage,

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project to, towards the region that processes, the

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stimulus at the, at the later, later stage.

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So these feedforward projections, mainly target the,

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the middle layer, layer four.

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Um, there are also projections from the higher

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vi, higher visual areas to lower vi visual areas.

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And these mainly, target layer one.

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So they, they go, they come from, from,

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neurons that, are above layer four in,

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in the source area and the target layer one in the,

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in, in the target area.

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Um, no, sorry, this was, a mistake.

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So we'll have to, do we take, do this again?

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So, the, the, the,

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the way the connections are, are arranged in, in the,

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in the hierarchy in the following.

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So connections, from the lower areas,

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so the areas that process the,

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the stimulus at an early stage, they,

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mainly, the,

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these neurons are mainly located in, above layer four,

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and they, they tie target layer four of,

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of, of the target area.

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Um, in contrast the, the opposite, the,

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the corrections done in the opposite directions.

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So from a higher, area to a lower area,

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they, originate in the, in those layers that,

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are below layer four.

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And then they, they target layer one of the, of the,

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of the low lower area in the early, two,

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2000 tests, 2020.

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So, few, a few year years ago, this

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has been, confirmed al also in, in mice.

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Uh, so injections, with injections

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with tracers, enabled the, the visualizations of,

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of these projections be between areas.

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They, based on, on the patterns of,

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of, of these projections.

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So, when you, when, when you followed the,

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the path from, from, along the,

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along the course cortex, once the visual stimulus,

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enters the, the, the, the main area

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of the visual, the V one.

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So afterwards, when you follow the, the pathway, the path

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of, of these, projections

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and their, their patterns, it was able to build a,

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a hierarchy based on how, on how

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feet forward and feedback,

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connections were, were arranged.

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So this is, confirming, according

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to the structure, the structure

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of, of the projections.

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But, it, it was also confirmed, by using recordings

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of, of neurons.

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And, I said, one of,

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of the main features for, for a hierarchy is that,

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neurons, across hierarchy, they,

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they tend to respond,

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the higher the region is in hierarchy, the later the neuron

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responses to the, the visual, stimulus,

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and this was, was confirmed in mice, u using,

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various, recording methods including the genetic,

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the, the genetic tools.

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There are similarities,

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but there also important differences.

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So the, the similarities is that there,

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there is,

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the pattern of projections, so from, higher,

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from lower areas to higher areas

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and from, higher areas to, to lower areas.

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Um, there, there is a, a pattern of projections, like in,

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like in primates, these rules are not,

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are not identical,

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but the, there are important, similarities.

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So, for example, the feedback, projections tend

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to target layer one in, in both orders, both rodents

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and, primates.

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You also, have higher receptive field,

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fields along the, the hierarchy.

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So a receptive fields is a region in space

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to which, particular neuron re responds to.

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So if, if you look at the activity of a, of a neuron

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and, you stimulate a certain part of, part

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of the space and, to that part of the space, the neuron,

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response, then that, that's the, the receptive field.

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And, the lower the,

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Uh, the, the higher the area in the hierarchy,

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the higher the, the receptive field,

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it is for, for a neuron.

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So you go from V one, in, in primary V one, V two,

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V three, and then the, the receptive fields

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of the neurons in these, areas, increase.

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And, it is the, the same in, in, in,

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in rodents.

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Um, and there is, as I mentioned, the,

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the delayed response, along the, the hierarchy, how,

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however, these, are

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there, there are, also important differences.

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So, for example, the density of, of connections in,

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in the visual system of the, of mice, oma,

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all the connections that, can exist, do, do exist

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while in the visual system of, primates,

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about 66% of the connections that can exist,

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do, do exist.

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So, significantly less, less connections in,

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in primates.

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And, another difference it is that the,

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the hierarchy is shallow.

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So you, you have, about,

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1.4 levels in mice compared

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with the 10 levels in, in Macca.

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And, this, this can,

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partially be explained by, by the fact that in mice, you,

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you only have about 10, 10 areas

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that occupy 15% of the neocortex.

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While in, in primates, in macx, for example,

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you have about 30 areas that process, visual stimuli,

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and they occupy half of, the, the, the neocortex.

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And the, the result of,

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this shallowness shallowness in the hierarchy is

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that it takes only four steps of the hierarchy to,

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to reach neurons that have about, for, for degrees,

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receptive fields.

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So,

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part in the space, an angle in the space about,

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40 degrees while, in,

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maca in, in, in primates, in contrast,

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there are about 10 steps needed to reach a similar,

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similar dimension of the receptive fields.

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And, this shallow hierarchy, could also imply

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that the representation

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of the visual features in mice are themselves,

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less sophisticated than in primates.

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We've been, speaking about, hierarchy to,

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to which we understand that the,

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The processes, the processing

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of the stimulus is done in sequences.

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Uh, and, one might imagine

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that, this is exclusively done in sequences, meaning

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that, a lower level,

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does processing

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and then passes the information to the next level,

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and then the next level passes, does another type

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of processing and passes, to the next level and,

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and so on, should the, the reality is, more, more,

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more complex than than that.

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Uh, there are, for example,

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because of, of these, high density of,

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of projections where everybody's connected to everybody,

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there are,

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communications between, many, many, many levels

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of, of hierarchy.

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Um, and, also,

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this, this implies that, the,

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the, the model of, of how

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the processing is done in the visual cortex is, is,

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is more complex than, than that.

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It also had, was, discovered that,

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for example, in mice two, two areas,

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two visual areas, am

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and pm, they should be, should be

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higher in the hierarchy than pm and

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therefore it should respond.

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The neurons there should be, respond, later

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to the visual stimuli com.

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Compared to pm however, about 27% of,

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of neurons in pm, so in the lower area, respond

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after after am.

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So, the

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therefore, it's, the,

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the model of, of a strict hierarchy, strict hierarchy,

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has to be, has to be more nuance.

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There, there are also known divergent projections from,

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from, V one, so from the first level of hierarchy

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to to, to the other, areas in,

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in mice.

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So, neurons in V one, projecting to two or three,

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or even, or,

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or even four, visual areas simultaneously, meaning

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that they convey information to all, all these other,

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areas, simultaneously.

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So, this, this is,

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in, in conflict with the fact that the,

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the information is, is, processed sequentially.

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So, this is, all, all, this is not to say that the,

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the hierarchy does not exist,

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but, actually,

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00:20:56.485 --> 00:21:00.655
most probably some features are processed hierarchically in

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this se, serial fashion, while others,

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00:21:04.765 --> 00:21:09.095
depending on the, on the importance for, for the,

342
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for the organism and for, for the,

343
00:21:13.555 --> 00:21:18.255
vi visual scene, they, they might be processed,

344
00:21:18.995 --> 00:21:21.415
faster, more, more directly.

345
00:21:21.475 --> 00:21:23.455
But I would like to add is that,

346
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although, all these, genes, all,

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all these gen genetic tools are available in mice

348
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and, people, can do, many,

349
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complicated types of, studies in mice

350
00:21:40.135 --> 00:21:44.215
and, fast results can, can be,

351
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can be obtained.

352
00:21:46.395 --> 00:21:49.935
Um, it, it's, it's still not the,

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00:21:50.315 --> 00:21:54.695
the ideal model, for, for setting the, the,

354
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the visual system, for, for many,

355
00:22:00.285 --> 00:22:01.705
for many reasons.

356
00:22:01.845 --> 00:22:06.535
So, it, it is still,

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the, the, the mouse brain is still very, very small

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complaint, compared to, any other pri brain.

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And, it,

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there are many details in, in the structure of, of the

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areas and, and on the projections between the areas

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and the way the, the neurons, function that, are,

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00:22:33.275 --> 00:22:34.935
are specific to, to mice.

364
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And, in the end might not be, relevant

365
00:22:39.975 --> 00:22:44.695
to understand how, of,

366
00:22:45.925 --> 00:22:49.615
more advanced feature features of the visual, system,

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OO operate, advanced features that, that,

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are, present only in primates.

Quick Answers

Complexity of Primate Visual System

00:00:00 - I think the, the start of, of addressing this question is to, to clarify what a visual system needs to, solve to, to, to address for the organism to which it belongs. So the, to put it very, very simply, the visual system in the, in, in the brain, it needs to account for the position of the self in, in space

00:00:31 - and position of other objects in, in space to which the, the self will, will interact, and also for the, the speed of, of all the, the above. So for the speed of the self and for the speed of, of the, the objects through which it, will interact. So, in this aspect, the, the primates are, are the, have the most advanced visual system because they, they can interact in a very complex,

00:01:07 - And they, can, react very, very cleverly to, different situations. And that may appear, during the, the lifetime. and this is, reflected in, the visual, cortex of, of the private, like the, the amount of, neurons that are, dedicated to, process

Comparing Visual Systems: Primate vs. Mouse

00:01:40 - the visual cues and, the visual information, but in the primate visual cortex contains, about 30, regions that respond to visual stimuli. And these regions, cover, more than half of the neuro cortex. And by comparison, the, the regions that respond to visual stimuli in mice, they, they were thought to be about four, so, up in the,

00:02:11 - And, it was known that they, they by about 15%, of, the, of the neocortex. So a much lower, lower proportion. And, for this reason, the mouse was not considered to be, to have an ideal visual, system to, to be a, an ideal model to study the, the, the visual system. So due to this, the small brain size

00:02:44 - but, the, the breakthrough, here came, around 2007, when it, it was discovered that actually the visual system in mice is, much more complex that, originally had been, had been taught. And it actually, contains, some forms of, of the processing that, that,

Significance of Genetic Tools in Neuro Study

00:03:13 - These genetic tools, used to, to study the, the brain in general, and the visual system in, in particular are, are very important because they, the, they target specific types they like, they can target specific types of, of neurons. So, it is well known that the patterns of gene expression depend on the types of neurons

00:03:45 - What you do is what, once you, you identify a gene that it is possible to make the neurons expressing that gene to become fluorescent throughout their cell body accents and then drives. And, in this way, you can, visualize, the pattern of projections of these neurons or, you can, make the, the same neurons vary their, their fluorescence in direct proportion to their electrical activity.

00:04:16 - outside world, these neuro ones, respond. But in order to, get these, these genetics tools, one often needs several generations of, of animals. And mice are, ideal for, for this because, they have a first, a rapid, reproduction, rate. So, and, their gestation is about, three weeks.

Mouse vs. Maca: Reproductive Contrasts & Research Impact

00:04:47 - to reach maturity is about six weeks. So in, less than three months, you have about five function adult males from, from a female. And, by comparison, if you work with Maca, let's say from the moment of conception, you need to wait for, about three, four years to, to have, a functioning, adult maca. And, by,

00:05:22 - you know, to have, by using mice in, in this, in this way, one could, could, could, it, it, yeah, it was a, a high, it was a basically a, an explosion of, studies that, that could, address, these,

00:05:52 - it could this, complex problems like, the patterns of projections and, the, the patterns of responses of, of, various types of neurons to, to define the, define visual stimuli, first, we need to define what, what the, what the hierarchy, means in, in this context. So, a hierarchy in, in the context

Processing Complexity in Visual System

00:06:27 - enters, the, the retina, then, it, the information contained in, in the, in the visual stimulus is processed in, in steps. And, the, the later these, these, processing, this processing is done, the higher the region that does the processing is in, in the hierarchy.

00:06:56 - the visual system has this in incredibly complex task to, it receives, stimuli, vis visual ti stimuli, yeah, on, on two retinas. So basically two, two to the, images. And then it needs to figure out the, the position of the self, the position of other objects and the, the movement that, everybody has, in,

00:07:32 - So, there, there are a lot of transformations to be done, and, these, these transformation, are, are done, sequentially. so, there, there are two aspects of, of this hierarchy. one can follow up the, the connections that go from the retina, along, to the thalamus

Neural Connections and Visual Processing.

00:08:00 - and how, this, the, these connections are, are, are done through, throughout, throughout the brain. And then, one, one can do this, from the point of view of physiology and, see, record at what times, various, regions respond to, to visual stimuli. So for, for the structural, anatomy.

00:08:33 - the connections, it, it's, has been well documented, since about 50 years, ago, that there are rules in in which, by, by which the, the projections are, are, are done from, and lower hierarchical Region to a higher hierarchical region in, in the brain. So main, the, the cortex, now

00:09:09 - of the regions of the cortex are composed of, six layers. And, the rule is that, feedforward, projections, so, projections from a, a, a region that processes the stimulus at an early stage, project to, towards the region that processes, the stimulus at the, at the later, later stage.

Visual System Connections Hierarchy

00:09:40 - the middle layer, layer four. there are also projections from the higher vi, higher visual areas to lower vi visual areas. And these mainly, target layer one. So they, they go, they come from, from, neurons that, are above layer four in,

00:10:10 - in, in the target area. no, sorry, this was, a mistake. So we'll have to, do we take, do this again? So, the, the, the, the way the connections are, are arranged in, in the, in the hierarchy in the following. So connections, from the lower areas, so the areas that process the,

00:10:41 - mainly, the, these neurons are mainly located in, above layer four, and they, they tie target layer four of, of, of the target area. in contrast the, the opposite, the, the corrections done in the opposite directions. So from a higher, area to a lower area,

Hierarchical Projections in Visual Cortex

00:11:13 - are below layer four. And then they, they target layer one of the, of the, of the low lower area in the early, two, 2000 tests, 2020. So, few, a few year years ago, this has been, confirmed al also in, in mice. so injections, with injections

00:11:47 - of these projections be between areas. They, based on, on the patterns of, of, of these projections. So, when you, when, when you followed the, the path from, from, along the, along the course cortex, once the visual stimulus, enters the, the, the, the main area of the visual, the V one. So afterwards, when you follow the, the pathway, the path

00:12:17 - and their, their patterns, it was able to build a, a hierarchy based on how, on how feet forward and feedback, connections were, were arranged. So this is, confirming, according to the structure, the structure of, of the projections. But, it, it was also confirmed, by using recordings of, of neurons.

Visual Hierarchy in Neurons

00:12:51 - of the main features for, for a hierarchy is that, neurons, across hierarchy, they, they tend to respond, the higher the region is in hierarchy, the later the neuron responses to the, the visual, stimulus, and this was, was confirmed in mice, u using,

00:13:22 - the, the genetic tools. There are similarities, but there also important differences. So the, the similarities is that there, there is, the pattern of projections, so from, higher, from lower areas to higher areas and from, higher areas to, to lower areas.

00:13:53 - like in primates, these rules are not, are not identical, but the, there are important, similarities. So, for example, the feedback, projections tend to target layer one in, in both orders, both rodents and, primates. You also, have higher receptive field, fields along the, the hierarchy.

Visual System Hierarchy Differences

00:14:26 - to which, particular neuron re responds to. So if, if you look at the activity of a, of a neuron and, you stimulate a certain part of, part of the space and, to that part of the space, the neuron, response, then that, that's the, the receptive field. And, the lower the, the, the higher the area in the hierarchy,

00:14:57 - it is for, for a neuron. So you go from V one, in, in primary V one, V two, V three, and then the, the receptive fields of the neurons in these, areas, increase. And, it is the, the same in, in, in, in rodents. and there is, as I mentioned, the, the delayed response, along the, the hierarchy, how,

00:15:33 - there, there are, also important differences. So, for example, the density of, of connections in, in the visual system of the, of mice, oma, all the connections that, can exist, do, do exist while in the visual system of, primates, about 66% of the connections that can exist,

Visual Hierarchy Differences in Mice and Primates

00:15:59 - So, significantly less, less connections in, in primates. And, another difference it is that the, the hierarchy is shallow. So you, you have, about, 1.4 levels in mice compared with the 10 levels in, in Macca. And, this, this can, partially be explained by, by the fact that in mice, you,

00:16:33 - that occupy 15% of the neocortex. While in, in primates, in macx, for example, you have about 30 areas that process, visual stimuli, and they occupy half of, the, the, the neocortex. And the, the result of, this shallowness shallowness in the hierarchy is that it takes only four steps of the hierarchy to,

00:17:07 - receptive fields. So, part in the space, an angle in the space about, 40 degrees while, in, maca in, in, in primates, in contrast, there are about 10 steps needed to reach a similar, similar dimension of the receptive fields. And, this shallow hierarchy, could also imply

Visual Processing Complexity in Mice vs. Primates

00:17:37 - of the visual features in mice are themselves, less sophisticated than in primates. We've been, speaking about, hierarchy to, to which we understand that the, The processes, the processing of the stimulus is done in sequences. and, one might imagine that, this is exclusively done in sequences, meaning that, a lower level,

00:18:11 - and then passes the information to the next level, and then the next level passes, does another type of processing and passes, to the next level and, and so on, should the, the reality is, more, more, more complex than than that. there are, for example, because of, of these, high density of, of projections where everybody's connected to everybody, there are,

00:18:46 - of, of hierarchy. and, also, this, this implies that, the, the, the model of, of how the processing is done in the visual cortex is, is, is more complex than, than that.

Hierarchical Model Complexity in Mice Visual System

00:19:17 - for example, in mice two, two areas, two visual areas, am and pm, they should be, should be higher in the hierarchy than pm and therefore it should respond. The neurons there should be, respond, later to the visual stimuli com. Compared to pm however, about 27% of, of neurons in pm, so in the lower area, respond

00:19:47 - So, the therefore, it's, the, the model of, of a strict hierarchy, strict hierarchy, has to be, has to be more nuance. There, there are also known divergent projections from, from, V one, so from the first level of hierarchy to to, to the other, areas in, in mice.

00:20:22 - or even, or, or even four, visual areas simultaneously, meaning that they convey information to all, all these other, areas, simultaneously. So, this, this is, in, in conflict with the fact that the, the information is, is, processed sequentially.

Complexity of Visual Processing in Mice

00:20:52 - the hierarchy does not exist, but, actually, most probably some features are processed hierarchically in this se, serial fashion, while others, depending on the, on the importance for, for the, for the organism and for, for the, vi visual scene, they, they might be processed,

00:21:21 - But I would like to add is that, although, all these, genes, all, all these gen genetic tools are available in mice and, people, can do, many, complicated types of, studies in mice and, fast results can, can be, can be obtained. it, it's, it's still not the,

00:21:54 - the visual system, for, for many, for many reasons. So, it, it is still, the, the, the mouse brain is still very, very small complaint, compared to, any other pri brain. And, it, there are many details in, in the structure of, of the

Mice Neuron Function Specificity

00:22:27 - and the way the, the neurons, function that, are, are specific to, to mice. And, in the end might not be, relevant to understand how, of, more advanced feature features of the visual, system, OO operate, advanced features that, that,

00:22:55 -

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