Trace a nerve impulse from the retina to the visual cortex?
405112
1. Photon hits photoreceptor.\n2. Signal is transduced from photoreceptor to bipolar cells, then to retinal ganglion cells.  There is some retinal processing that occurs that involves horizontal and amacrine cells.  \n3. Signal goes through optic nerve, which takes the signal out of the retina into the lateral geniculate nucleus (LGN).  \n4. Signal goes from the LGN to the visual cortex, where the signal is further processed.  \n\nThat's really brief, but I hope that helps!
193366
A nerve impulse is the electro-chemical signal that is initiated between nerve synapses(the gaps between nerve endings). The primary agent for this is ace·tyl·cho·line ,a neurotransmitter C7H17NO3 released at autonomic synapses and neuromuscular junctions and formed enzymatically in the tissues from choline.
1184007
The colored part of your eye is the iris, and all it does is control the amount of light that passes into the eye by varying the size of your pupil.  Light passes through that opening to the retina at the back of the eye where the rods and cones convert the lightwaves into the nerve signals that your brain recognizes as objects, colors, etc.
381087
I read about this.  It happens in bright light because the optical and nasal nerves are so close together.  The brain is receiving all these signals from both that are so close together that it can sort of trick itself.
587179
The brain is the organ that composes the image the eyes send. So the vision that involves movement, profundity, distant, brightness occurs in the eyes. But the vision is not complete without interpretation. So if you can't understand what you are seeing you may not see at all.
620358
Your photoreptors and your visual cortex cells randomly fire, it is background noise a bit like you get with a CCD camera. Also you may notice that if you put pressure on your eyeball (not too much!) you will see a bright spot - so photoreceptors respond to more that just light.\n\nI get this too and my vision is fine.
278992
label the known protein with a radioactive isotope, or better yet, maybe you could label the protein with a flourescent dye (dont know how, its beyond my expertise) and where ever the protein binds on the receptive cell may be what you're looking for.  but i dont know of any assays per se for it.
581711
The word you are looking for is Phosphene.\n\nPhosphenes are the light sensation you experience often from pressure/stimulus on your retina.
344053
The other answers are okay as far as they go.  However, the unique feature of the retinal ganglion cells is that they are the only cells (i.e. defined as the cells) that project out of the retina to the brain.  The other cells in the retina make their connections within the retina.
1185534
I think you would do well to look a while at this excellent - but - simpliefied source on neuroscience:\n\nhttp://faculty.washington.edu/chudler/introb.html
292143
In your eyes. But vision actually takes place at the back of the brain.
752479
an electrical wave that travels down the membrane of a cell
1144813
Some nerve cells around the sight of the injurty are invariably dead. However the vast majority are still perfectly functional. The area of dead neurons means they can not transmit information to the brain.
194983
Assuming it passes through the cornea and lens and hits the retina, it'll be absorbed by the cells of the retina. Its energy is used in the chemical reaction in the cell which creates the nerve impulse that passes to your brain and allows you to "see" the light.
535997
no, feature detection is done by other cells, e.g. center surround detection in retinal ganglion cells, but also by cells in the visual cortex of the brain. \nWhere and how depends on what feature you are talking about.
318711
go to http://images.google.com type brain
7088
Hey, here's another idea you haven't worried about yet:\n\nSince nerve impulses travel at about 35 ft/sec, the sensory nerve impulses arrive at our brains a fraction of a second after the stimulus.  And, since our sense organs are separated from our brains by different distances, their arrival isn't coordinated.  Furthermore, it takes a bit for our brains to process the signals and for the motor nerve impulses to travel to our muscles to respond.  All together, we loose about one second from the time something happens until we can react to it.  We are all living about a second in the past, and different parts of our bodies are living in the past by different amounts.\n\nOne way this is important is in driving.  Whether your car has incandescent brake lights or LED brake lights can make the difference in whether you get hit by the car behind you.  LED lights turn on about one-fourth second faster than incandescent lights, giving the person behind you a little extra time to react to your braking.\n\nAt 50 mph, a car travels 73 ft/sec and the stopping distance is 173 ft.  Another one-quarter second gives the person an extra 18 ft to stop.