Becoming aware of the eye's blindspot??

[gingles]

This might sound like an odd thing to ask about, but is it possible that i might have just become aware of my eye's blindspots?

For example, if i sit in front of a monotone bright surface, i am aware of a tiny "blotch" just to the right and down from my focal point of right eye and an almost identical one to the left and down of the focal point of my left eye. But when i move my eyes to try and follw the blotch i lose it. This is only something i've just become aware of in the last few weeks though.

This is quite a difficult experience to have explained, and i hope it's clear enough to have some sort of explanation from somebody?

[Air Conditioned]

Gingles,

You do not seem to have a reply to your query of some weeks back. This is well known and should be explained in any Aviation Medicine document.

The blind spot is where the optic nerve enters the eyeball and does not respond to light, or sight is fuzzy at best.

You can locate and demonstrate it with a piece of card with two symbols on it, say an O and an X about 5cm apart. Hold the card about 60cm away, with the O-X axis horizontal, and focus on the O and observe that the X is visible, and remains so while moving the card towards the eye. When fairly close the X will disappear (or become too fuzzy to see). You will be able to see that other items outside the blind spot are still visible, ie, it is a spot, not a cut-off point. You have already seen this effect.

The function is important for pilots, since it is entirely possible for an object to be overlooked (pardon the expression) if it happens to fall into that place. Therefore if you are looking for air traffic, etc, you must scan continuously.

[Loose rivets]

I used to notice that if I was tired, especially after long drives, that I became more aware of my blind spots. I knew what they were, but sometimes they seemed alot bigger and intrusive.

[Farmer 1]

I await to be shot down in flames on this, but if you can see a "blotch", however tiny, then it is not a blind spot (because you can see it - geddit?). If you do as Air Conditioned describes, the symbol disappears, it does not turn into something else.

What he does not say is that you must have one eye closed for the experiment to work, and if you use your right eye you look at the symbol on the left for the other one to disappear.

So, if you are experiencing this with both eyes open, then I suggest a visit to an optician is called for, and as soon as possible.

Good luck.

[Loose rivets]

A layman's view point...ho, ho.

The problem with blind spots is that the brain is very good at painting in the missing information. You may think that this can only be done from information from the other eye, but this would be wrong.

So powerful is this function, that there have been cases of ‘blindness denial' in totally blind people. The statistics on this have to be taken as suspect, because of the human trait of seeking attention.

Considering how common such ‘filling in' data is in electronic video, for the brain to do it is not really very surprising.

The field test is better than I would have guessed it could be. After some time as a guinea pig, the computer printed out an almost perfect plan of my visual field. I had been very undecided on some of the stimuli, and was sure that the plan was going to be a poor representation.