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Visual Pigments in Man
1156
BOOK
T h i s v o l u m e is available in m o s t medical libraries a n d d e s e r v e s perusal.
R E V I E W S
principle that a flashing light is m o r e easily seen against a bright b a c k g r o u n d if colored,
David Shoch.
obtained accurate sensitivity c u r v e s f o r the red, green a n d blue m e c h a n i s m s , respectively. H.
All this supports the conclusion that there
Springfield, 111.
are three visual p i g m e n t s , each connected to
Charles C T h o m a s , 1 9 6 2 . 3 8 p a g e s plus
a separate cone output, an idea first p r o p o s e d
ix, 16 figures, bibliography. P r i c e : $ 3 . 7 5 .
by T h o m a s Y o u n g in 1802.
VISUAL
PIGMENTS
Rushton,
Sc.D.,
IN
MAN.
F.R.S.
By
W.
A.
In this S h e r r i n g t o n Lecture, R u s h t o n , the distinguished p h y s i o l o g i s t o f the U n i v e r s i t y of Cambridge, interprets the results of recent refined e x p e r i m e n t s o n the nature of the visual p i g m e n t s in the h u m a n e y e . H i s scientific p r o f u n d i t y is, a s usual, presented with clarity and spiced with h u m o r . T h a t r h o d o p sin mediates h u m a n scotopic vision, h a s been conclusively d e m o n s t r a t e d . A n e y e w i t h a s o u n d retina, destined for enucleation, w a s kept c o v e r e d a n d e x c i s e d in red light. T h e r h o d o p s i n extracted revealed an absorption spectrum that coincided precisely with h u m a n scotopic visibility (Crescitella and Dartnall, 1 9 5 3 ) . R u s h t o n and Campbell determined the actual density of r h o d o p s i n under v a r i o u s c o n d i t i o n s f r o m a quantitative study of t h e blue-green light reflected from the h u m a n retina. C o m p a r i s o n s of t i m e a n d intensity s h o w e d that for 4 5 s e c o n d s the B u n s e n R o s c o e l a w held, indicating for this period a purely chemical response. T h e rods w e r e found to be visually inoperative w i t h less than 9 0 percent of their rhodopsin. T h e equivalent light of a s u m m e r day ( 1 0 , 0 0 0 m i l l i l a m b e r t s ) caused rhodopsin to be n o m o r e than half bleached. T e s t i n g the f o v e a similarly, R u s h t o n f o u n d that the protanope has o n l y the g r e e n - c a t c h i n g pigment, while the normal p e r s o n h a s also the red-catching pigment. T h e blue p i g m e n t could n o t be thus detected. T h e blue receptors cannot be rods since they s h o w a retinal directional effect w h i c h rods do not ( S t i l e s , 1 9 3 9 ) . T h o u g h the f o v e a of the protanope lacks t h e red p i g m e n t , it h a s twice the normal a m o u n t o f g r e e n p i g m e n t . A s v i t a m i n A serves both rods a n d c o n e s , the genetic absence o f the red p i g m e n t probably signifies a defect of specific protein. Stiles ( 1 9 5 3 ) , u s i n g the
James E . Lebensohn. T r a n s a c t i o n s o f the F i r s t C o n g r e s s o f the E u r o p e a n Ophthalmological Society. Edited b y J. F r a n ç o i s . Basel, S. K a r g e r , 1 9 6 1 . Available in the U . S . A . through Albert J. P h i e b i g , W h i t e P l a i n s , N . Y . Price $ 1 9 . 0 0 .
SECONDARY GLAUCOMA:
T h e first c o n g r e s s o f the E u r o p e a n O p h thalmological S o c i e t y w a s held in A t h e n s in April, I 9 6 0 . T h e subject of the entire conference w a s secondary glaucoma a n d 58 papers w e r e presented o n this subject. T h e official l a n g u a g e s o f the c o n g r e s s were F r e n c h , G e r m a n a n d E n g l i s h a n d about o n e third of the papers w e r e g i v e n in each ( w i t h the e x c e p t i o n of o n e in S p a n i s h and t w o in Italian). T h i s book is actually a treatise on the subject of secondary glaucoma since almost e v e r y s y s t e m i c a n d local disease with an associated increase in intraocular p r e s s u r e is discussed. F o r e x a m p l e , the first section discusses uveitis, heterochromic iritis and postoperative glaucoma. T h e second section i n cludes papers o n g l a u c o m a due to lens swelling, h y p h e m a , v e n o u s obstruction a n d t h r o m bosis, essential atrophy of the iris, rubeosis iridis a n d t h y r o g e n i c e x o p h t h a l m o s . T h e final section consists of m i s c e l l a n e o u s papers o n g l a u c o m a secondary t o a variety of c a u s e s , as well a s an interesting paper o n the electro32tinographic c h a n g e s in secondary glaucoma. T h e final paper, o n the functional state of the n e r v o u s s y s t e m in secondary g l a u c o m a , is, appropriately e n o u g h , b y A . D . P a v l o v . All the papers collected in this v o l u m e have been published in O p h t h a l m o l o g i c s , volu m e 1 4 2 , N o . 1 a n d 2 a n d a supplement. H o w e v e r , the rather i n t e r e s t i n g o p e n i n g ad-
BOOK
T h i s v o l u m e is available in m o s t medical libraries a n d d e s e r v e s perusal.
R E V I E W S
principle that a flashing light is m o r e easily seen against a bright b a c k g r o u n d if colored,
David Shoch.
obtained accurate sensitivity c u r v e s f o r the red, green a n d blue m e c h a n i s m s , respectively. H.
All this supports the conclusion that there
Springfield, 111.
are three visual p i g m e n t s , each connected to
Charles C T h o m a s , 1 9 6 2 . 3 8 p a g e s plus
a separate cone output, an idea first p r o p o s e d
ix, 16 figures, bibliography. P r i c e : $ 3 . 7 5 .
by T h o m a s Y o u n g in 1802.
VISUAL
PIGMENTS
Rushton,
Sc.D.,
IN
MAN.
F.R.S.
By
W.
A.
In this S h e r r i n g t o n Lecture, R u s h t o n , the distinguished p h y s i o l o g i s t o f the U n i v e r s i t y of Cambridge, interprets the results of recent refined e x p e r i m e n t s o n the nature of the visual p i g m e n t s in the h u m a n e y e . H i s scientific p r o f u n d i t y is, a s usual, presented with clarity and spiced with h u m o r . T h a t r h o d o p sin mediates h u m a n scotopic vision, h a s been conclusively d e m o n s t r a t e d . A n e y e w i t h a s o u n d retina, destined for enucleation, w a s kept c o v e r e d a n d e x c i s e d in red light. T h e r h o d o p s i n extracted revealed an absorption spectrum that coincided precisely with h u m a n scotopic visibility (Crescitella and Dartnall, 1 9 5 3 ) . R u s h t o n and Campbell determined the actual density of r h o d o p s i n under v a r i o u s c o n d i t i o n s f r o m a quantitative study of t h e blue-green light reflected from the h u m a n retina. C o m p a r i s o n s of t i m e a n d intensity s h o w e d that for 4 5 s e c o n d s the B u n s e n R o s c o e l a w held, indicating for this period a purely chemical response. T h e rods w e r e found to be visually inoperative w i t h less than 9 0 percent of their rhodopsin. T h e equivalent light of a s u m m e r day ( 1 0 , 0 0 0 m i l l i l a m b e r t s ) caused rhodopsin to be n o m o r e than half bleached. T e s t i n g the f o v e a similarly, R u s h t o n f o u n d that the protanope has o n l y the g r e e n - c a t c h i n g pigment, while the normal p e r s o n h a s also the red-catching pigment. T h e blue p i g m e n t could n o t be thus detected. T h e blue receptors cannot be rods since they s h o w a retinal directional effect w h i c h rods do not ( S t i l e s , 1 9 3 9 ) . T h o u g h the f o v e a of the protanope lacks t h e red p i g m e n t , it h a s twice the normal a m o u n t o f g r e e n p i g m e n t . A s v i t a m i n A serves both rods a n d c o n e s , the genetic absence o f the red p i g m e n t probably signifies a defect of specific protein. Stiles ( 1 9 5 3 ) , u s i n g the
James E . Lebensohn. T r a n s a c t i o n s o f the F i r s t C o n g r e s s o f the E u r o p e a n Ophthalmological Society. Edited b y J. F r a n ç o i s . Basel, S. K a r g e r , 1 9 6 1 . Available in the U . S . A . through Albert J. P h i e b i g , W h i t e P l a i n s , N . Y . Price $ 1 9 . 0 0 .
SECONDARY GLAUCOMA:
T h e first c o n g r e s s o f the E u r o p e a n O p h thalmological S o c i e t y w a s held in A t h e n s in April, I 9 6 0 . T h e subject of the entire conference w a s secondary glaucoma a n d 58 papers w e r e presented o n this subject. T h e official l a n g u a g e s o f the c o n g r e s s were F r e n c h , G e r m a n a n d E n g l i s h a n d about o n e third of the papers w e r e g i v e n in each ( w i t h the e x c e p t i o n of o n e in S p a n i s h and t w o in Italian). T h i s book is actually a treatise on the subject of secondary glaucoma since almost e v e r y s y s t e m i c a n d local disease with an associated increase in intraocular p r e s s u r e is discussed. F o r e x a m p l e , the first section discusses uveitis, heterochromic iritis and postoperative glaucoma. T h e second section i n cludes papers o n g l a u c o m a due to lens swelling, h y p h e m a , v e n o u s obstruction a n d t h r o m bosis, essential atrophy of the iris, rubeosis iridis a n d t h y r o g e n i c e x o p h t h a l m o s . T h e final section consists of m i s c e l l a n e o u s papers o n g l a u c o m a secondary t o a variety of c a u s e s , as well a s an interesting paper o n the electro32tinographic c h a n g e s in secondary glaucoma. T h e final paper, o n the functional state of the n e r v o u s s y s t e m in secondary g l a u c o m a , is, appropriately e n o u g h , b y A . D . P a v l o v . All the papers collected in this v o l u m e have been published in O p h t h a l m o l o g i c s , volu m e 1 4 2 , N o . 1 a n d 2 a n d a supplement. H o w e v e r , the rather i n t e r e s t i n g o p e n i n g ad-