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General Anatomy of the Eye
& Degenerative Diseases
of Human Retina
Jennifer Hsieh
Psy 159
Physiological Basis of Perception
1/11/2005
Medical ppt
http://hastaneciyiz.blogspot.com
Background
Key Terms
 Vitreous humor – fluid in major chamber of eye.
 Retina – encodes the info as a neural signal to transmit
to the brain.
 Macula lutea – pigmented central region of the retina
containing fovea.
 Fovea – greatest capacity for fine detail discrimination.
 Optic nerves – bundle of ganglion cell axons carrying
visual info.
 Cornea – where light enters the eye.
 Iris – a smooth ring of muscle with a central opening.
 Pupil – central opening.
 Lens – helps the cornea to produce a focused image.
Anatomy of the Retina
Photoreceptors
(Rods and Cones)
Outer Plexiform Layer
Inner Nuclear Layer
Inner Plexiform Layer
Ganglion Cells
The Retina
 Receptors – absorb photons & begin to create neural signals.
 Outer plexiform layer – the receptors terminate here.
 Inner nuclear layer  Horizontal cells: responsive to lights across a wide area of the
retina.
 Bipolar cells: response can be either hyperpolarizing (light falling
directly on it) or depolarizing (light falling to the side).
 Amacrine cells: produce response (transient / phasic) when the
light level changed.
 Inner plexiform layer – signals within bipolar cells conducted to here.
 Ganglion cells
– receive the end products of all the previous
processing and communicate it to the brain.
Retinal Photo - Ophthalmoscope
Degenerative diseases of the
human retina
 In some eye diseases, the retina becomes
compromised, and the degenerative changes
lead to serious damage to the nerve cells
that carry the messages about the visual
image to the brain.
Age Related Macular Degeneration
Age related macular degeneration - the macular area and fovea
become compromised due to the pigment epithelium behind the
retina degenerating and forming white spots.
Glaucoma
Glaucoma - the pressure within the eye becomes elevated. The
pressure rises because the anterior chamber of the eye cannot
exchange fluid properly by the normal aqueous outflow methods.
Retinitis Pigmentosa
Retinits pigmentosa - a hereditary disease of the retina. Most of
the faulty genes affect the rod photoreceptors. Characteristic
pathology is the occurrence of black pigment in the peripheral
retina and thinned blood vessels.
Diabetic Retinopathy
Diabetic retinopathy - a side effect of diabetes that can cause
blindness. The vital nourishing blood vessels of the eye become
damaged, distorted and multiply in uncontrollable ways.
Now that we are done,
take the quiz!

1. The _____ transmits electrical impulses from the eye to the
brain.
A. Lens
B. Optic nerve
C. Vitreous humor

2. The eye works a lot like a...
A. Camera
B. Computer
C. Projector

3. Below is a view of the fundus of the retina in a patient with
______.
A. Glaucoma
B. Healthy Eye (Normal)
C. Macular degeneration
References
 Hagerman, G.S. and Johnson, L.V. (1991) The photoreceptorretinal pigmented epithelium interface. "Principles and
Practice of Clinical Electrophysiology of Vision" (Eds.
Heckenlively, J.R. and Arden, G.B.) Mosby Year Book, St.
Louis, 1991, pp. 53-68.
 Henkind , P., Hansen, R.I. and Szalay, J. (1979) Ocular
circulation. In "Physiology of the human eye and visual
system" (Ed. Records, R.E.) pp 98-155. Harper & Row, new
York.
 Kolb, H. (1991) The neural organization of the human retina.
In "Principles and Practices of Clinical Electrophysiology of
Vision" (Eds. Heckenlively, J.R. and Arden, G.B.) Mosby Year
Book Inc. , St. Louis, pp. 25-52.
 Polyak, S.L. (1941) The Retina. University of Chicago Press,
Chicago.
 Van Buren, J.M. (1963) The retinal ganglion cell layer. Charles
C. Thomas, Springfield, Illinois.
THANK YOU
Medical ppt
http://hastaneciyiz.blogspot.com