-Near point is receding, lens gets thicker, the muscles get weaker therefore muscles
can’t bend lens as much, in order to bring the image onto the retina, therefore near
point gets far, and past the near point, one sees a blurry image.
-Presbyopia can be improved by wearing convex lens.
-Accomodation speed slows down: needed to adjust to change in distances.
-Visual acuity: the ability to tell apart small details of an image. Details can be
viewed better with a greater visual acuity.
-Visual acuity declines slowly, at 40 years, steepness of the slope increases therefore
acuity declines faster.
-At 80 years, one can see at an average of 20 feet, whereas an average 20 year old can
see at 200 feet.
Problems can occur in the optic nerve, or other organs.
-A lot of variability exists in terms of visual acuity among people- therefore a
question is asked: can practice with tasks that involve acuity, reduce the effects of
aging on acuity? Ex. shooting a basket ball
-It was found that there is a genetic predisposition to good visual acuity, however
training and practise can improve it. (both factors influence it)
Reduced Dynamic Visual Acuity: examines how one processes information in moving time.
Ex. reading signs on a bus as it moves.
Visual Field: if we keep our head still, and our eyes don’t move, everything we can see is
our visual field. After age 50, the size of the visual field reduces faster.
Depth perception: ex. look at a distance between things- researchers say that this occurs
due to a loss of binocular cells, which process information from the right and left eye
Processing of visual information: it takes longer to extract information form a source, and it
takes longer to do things.
As one gets older, one becomes more vulnerable to pathology.
Glaucoma: Leading cause of blindness: it is a steady increase in pressure in the interior
chamber: aqueous humor, which is responsible for bathing structures (is a part of the