Visual Processing and the Visual Cortex

We learned about the structure of the eye in the Anatomy and Physiology series. But how do we process visual information? Light hits the retina at the back of the eye, and then what happens? Well quite a lot, to be honest! We have to go deeper regarding retinal structure, neural pathways to the brain, and the regions of the brain that receive and process this information, which are collectively referred to as the visual cortex. So let's get a closer look!
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[@TH6NAM6L6SSv3]

Bruh, I read the section in my textbook on this about 15 times, and it just didnt click. You sir, are a gentleman and scholar.

[@unboxer2487]

Honestly speaking, this is the best video for vision explanation I have seen so far. Detailed, short, talking slowly and writing the key points. Perfect for teaching . Thanks professor Dave.

[@deanwidiani3244]

(2)!!! agreed. it helps a lot!

[@monisshathiagu2971]

[10:17] Just a tweak: glutamate is an excitatory neurotransmitter, and this is not an exception in the eye. The way it inhibits signal transduction, rather, is by stimulating the release of GABA in horizontal cells, which is an inhibitory neurotransmitter.

[@wrldrcrds6946]

Thank youu soo much. I got cofused at that part of the video.

[@nonamefound9296]

Heeey thank you so much I was getting confused

[@joneriksen9257]

@@nonamefound9296 Thanks. I was confused

[@HarryNicNicholas]

do you know what form information about light takes in order for the brain to create an image? how does the electr-chemical signal contain information? i hope this is clear.

[@kadri246]

Is this the reason why light therapy is a treatment?

[@voidofmisery4810]

I am learning this in college now, and you made this subject so much easier to understand!!! Thank you so much! I am so grateful for this!

[@jamesh6441]

You the TRUTH Prof. Dave! I truly appreciate everything you do on here!

[@mariesellers953]

I remember when I was taking Gen Chem 4 years ago, your videos helped me understand things so well. Now that I'm taking upper neuroscience courses, you're STILL pulling through. You're a God sent!!

[@KamauriKing-ii5ke]

His shoulders needed to hide there is an alphabet

[@centsury]

You’re really helping me getting through midterms! Thank you so much! Can’t wait for more videos on this subject.

[@knoz35]

In university it took 40 hours to complete all this. and you just made it possible to understand in 16 minutes. just wow. amazing!!

[@fredericomarques4230]

Great job Professor, a really complete session about vision and all its path!! Congrats!

[@mitsunori222000]

Just what I've been waiting for. Thanks.

[@RockerProf]

Fantastic video. Your visual graphics very well done and helpful.Thank you for making this. It helps me understand much better how musicians process sight reading musical notes.

[@emat731]

This was very informative and helpful, thank you!

[@lordpredator8855]

Hello Professor Dave. I am admiring the work that you do, I want to suggest a topic for a future video. Can you please explain, how does fermentation and mould work. Thank you

[@jean-antoinenorbert1346]

Really great content and presentation!

[@CamronWiltshire]

Great video! Thanks Professor Dave!

[@LiftersClinic]

Excellent review of the intersections topics that unite cell biology to organism.

[@hypothesised4453]

thank you for this v concise explanation of the three weeks of class content i missed while i was ill! :,)

[@marianbundel1229]

Simply amazing. Thank you very much Dave!!!!

[@Zetsuke4]

Very well explained Professor Dave.

[@mahekmamgain1008]

Sir your videos are literally great and they are really helping me in college.. ❤️❤️❤️❤️

[@ErisvaldoJunior]

Thanks a lot from Brazil!

[@MG-oi2zy]

Excellent explainations!

[@isaiasyoyo]

Helpful video. detailed, thank you.

[@agnesetretjakova5405]

Thanks for great explanation! 🙏

[@roksanadawil]

Thank you so much, that helped me a lot :) I learnt more about how does the visual system in our minds work :)

[@chaimareader6091]

Hi Professor Dave, Can you help please. I want to change the wavelength of the Bragg mirror according to random distribution But i don't have any idia about the mathimaticals formula used to discribed this variation.

[@wa8642]

Im speechless. This is too good

[@NikhilSharma-td3hr]

Fantastic Sir. Respect from India.

[@ahababkhan6803]

Thank you so much for special lacture ❤️ keep it up please

[@pratikdeshmukh241]

Nicely explain

[@sowsudh]

You mentioned about the axons converging in the optic nerve to create a 'disruption' that in turn creates a blind spot. Could you please help elaborate on that?

[@nikoscharalampidis7153]

Amazing stuff!

[@suffragettefashion]

❤ this was fantastic! I’m an artist seeking greater understanding of how our eyes process light.

[@ArleighLauren]

I am a visual learner so my textbook was so hard to comprehend! This video was amazinggg

[@goodnessnwanebu8662]

You’re the man, brother 💪

[@user-fq7tt6yc6t]

This was amazing.

[@Dr_mae7733]

Really Great Video

[@arkitchen2231]

What kinds of visual information reach the pons, and why this connection may aid in coordination, balance, and movement?

[@itzikovadia851]

Amazing video thank you

[@mohammaddaraeim.d4649]

thanks prof dave

[@ophthojooeileyecirclehisha4917]

thank you so much professor

[@snoogumsboogums28]

this is is such a good video

[@palomabrt]

This video is amazing

[@eugenelenskih2885]

Very good very informative.

[@pooyarazzaghi388]

Very nice! thanks

[@chudiergonywiel5587]

Great explain, I will be professor one day like you.

[@tarq2126]

Thank so match. Sorry. if tha retenal found in yodopseen toogther rodopseen. Or what?? Can help me.

[@lolk7726]

great video

[@DANGJOS]

Amazing!

[@AsiaUmarMasud-je3ii]

Please can talk about the Synaptic organisation of the retina

[@BunnyLang]

Thank you.

[@Keana43]

i totally get it now thanks

[@needexotics8447]

wow thank you so much❤

[@TheAceLewis]

Do you think biological enhancements or cybernetic enhancements will be leading the charge in correcting or upgrading human vision in the future?

[@TheVeryHungrySingularity]

What determines which wavelength of light a particular cone is activated by? Hypothetically, could they be altered to see into IR or UV wavelengths?

[@iliakorvigo7341]

> What determines which wavelength of light a particular cone is activated by The absorption spectrum of its visual pigment. > Hypothetically, could they be altered to see into IR or UV wavelengths Hypothetically, yes, though the problem is not as much about finding a suitable pigment, as it is about passing through and focusing IR or UV light. Basically, different types (wavelength ranges) of EM radiation require different materials and focusing systems. For example, liquid water is transparent for visible EM radiation, but opaque for UV and IR radiation.

[@shalinig2739]

Beautiful

[@Minimum1337]

THANK YOU!!!!!

[@mollystringer3722]

So this is all good and well (thank you so much oh my god, it was so helpful) but the on and off ganglion cells and how they work kind of broke my brain, so maybe make a video on those as well? Or if anyone has already made a video on those, I desperately need to be pointed in that direction.

[@joelsteiger4439]

thankyou so much! +1 psychology-student-life saved

[@pavirajapaksha7276]

best ever explanation 🥰🥰🥰🥰🥰🥰🥰🥰

[@sakunwanmosika6073]

Thanks

[@shreyasimhadri3863]

professor Dave you are a blessing and I thank you on the night before my biological psychology exam.

[@younginsane90]

How can I Destimulate my Visual Cortex ?

[@MKUltraTutorials]

Excellent video tons of information Thank you. Question: do you believe we can heal our vision with proper nutrition? Or you still believe that glasses are the only way?

[@ProfessorDaveExplains]

well if by heal you mean improve inborn visual deficits, i don't know enough to say definitively, but i would imagine that diet can't really have any effect. on the other hand in terms of maintaining eye health and normal vision as you age, i have heard there is a link with certain nutrients and that sounds pretty reasonable.

[@HarryNicNicholas]

@@ProfessorDaveExplains 8:00 sorry, but this is misleading. i know everyone does this - i've only seen one video on the subject - but cones don't detect colour - there is no colour in objects or light, colour exists - is created - only in the image making part of the brain. cones detect energy levels of photons, not colour. i came to this video because i am not clear how any information gets to the brain, that is, electro-chemical signals tell the brain about taste, smell, light, but how exactly is that information conveyed / encoded? it can't be digital (i imagine), and there certainly aren't tubes of paint snaking around the eye. i believe neurons work by transferring ionisation of sodium . potassium / chlorine, but how is the INFORMATION , the colour, the taste, encoded? and please do a video explaining that objects and light have no colour, this is a big misconception that the vast majority of people can't get their heads around - i'm tired of arguing with people on this. thanks!!

[@knufyeinundzwanzig2004]

@@HarryNicNicholas Why do you think the information can‘t be binary? As far as I know the output of neurons is binary, signal or no signal.

[@kadri246]

My go-to-guy to pass my exams... Thanks for the videos.

[@kbieberlove101]

professor dave needs his name on my degree

[@windigo000]

so many cortex wow 😁👍

[@pfc-5503]

why are your images and explanations better than my professors who went to Harvard?

[@ChappalMarungi]

Your profs went to Harvard?

[@pfc-5503]

⁠@@ChappalMarungi the one that taught neurology did

[@mohamedghonaim6598]

Great ❤

[@TheWheelBry]

Watching this made my eyes hurt😅 but it was very helpful, thank you!

[@shalinig2739]

9:26 visual transduction

[@khalifalkhatatbeh]

Can retinal cones regenerate like cells?

[@Mrbluesplayer43]

Visionary!

[@liuliumama]

exelent！

[@cl7934]

GOLD

[@ralcool5932]

I would like to postulate that a photon is a node, a wave interaction point.

[@CAMIDRCS]

Why are the ganglions facing the light?🤔 It should have been the cones & rodes right?!!!!

[@turanbirligi6969]

But how actually vision creating in the brain what is brain actually doing

[@dianat2002]

How did the color cones "evolve" to work only in the visible spectrum range. The eye would provide no way for the animal to see during the "evolution" process if say the photoreceptors were working in the Microwave range. Your video is good Dave but there is way more to explain if you want us to buy into your evolution idea. It appears from an engineering perspective that the eye had to be designed to work in the visible spectrum from the beginning. I noticed you left out the motion sensing circuits in the retina that wire to the Superior colliculus and then to the Tectospinal tract to create our visual reflexes, like when a ball is coming at your head. The eye does much more than just compress vision.

[@marcoss6212]

Thank you for this informative video, Bravo!, but I have a curious question, now I have a basic understanding how we process visual information, my question is this, has anybody ever determined how fast visual process take before we know what we are looking at? Maybe crazy for me to try to find an alternative to the notion that nothing travels faster than light, I know, I'm crazy :).

[@Misslayer99]

About .15 seconds but varies depending on individual's cognitive processing and image complexity

[@marcoss6212]

@@Misslayer99 Thank you.

[@mieczyslawherba2723]

Five senses are mentioned, only four named.

[@transcendentphilosophy]

Just remember, these explanations don't resolve the hard problem of consciousness!

[@amehak1922]

Is there anything you don't know about?

[@user-iy5db2ic2x]

Intergrated census.

[@jmo8a_veda]

Sometimes bright lights getin the house it makes me so mad. Esp when Im reading

[@TK-mv6sq]

Lit!

[@googleyoutubechannel8554]

Wait, wtf, is this as far as neuroscience has gotten? How does object detection work? Forget obj det. how does the brain parse visual info into pre-object subunits (eg maybe lines) How does the brain parse shadows etc to build 3d inference? This explains basically nothing.

[@transcendentphilosophy]

Calm down, its a short video. Can't explain everything in one video.

[@achrafabouras2118]

i wish i was smart

[@HarryNicNicholas]

8:00 sorry, but this is misleading. i know everyone does this - i've only seen one video on the subject - but cones don't detect colour - there is no colour is objects or light, colour exists - is created - only in the image making part of the brain. i came to this video because i am not clear how any information gets to the brain, that is, electro-chemical signals tell the brain about taste, smell, light, but how exactly is that information conveyed / encoded? it can't be digital (i imagine), and there certainly aren't tubes of paint snaking around the eye. i believe neurons work by transferring ionisation of sodium . potassium / chlorine, but how is the INFORMATION , the colour, the taste, encoded? and please do a video explaining that objects and light have no colour, this is a big misconception that the vast majority of people can't get their heads around - i'm tired of arguing with people on this.

[@daniel9973]

I believe you are referring to the hard problem of consciousness.

[@knufyeinundzwanzig2004]

Why did you comment this more than once?

[@ayadali9112]

First!

[@simonmoore8776]

There are more than five senses! A professor should know better!

[@jmo8a_veda]

Dam they let you post photos of eyes like that... Is this even legal..idk. sorry.

[@eatshitlarrypage.3319]

Good video and all, but there are quite a few more than five senses.