Home

About

Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network
FAQHELPSITE MAPCONTACT US


  Advanced Search  

 
Three-Dimensional Structure and Evolution of Primate Primary Visual
 

Summary: Three-Dimensional Structure and
Evolution of Primate Primary Visual
Cortex
ELIOT C. BUSH* AND JOHN M. ALLMAN
Biology Division, California Institute of Technology, Pasadena, California
ABSTRACT
In this study, three-dimensional reconstructions of primate primary visual cortex (V1)
were used to address questions about its evolution. The three-dimensional shape of V1 in
anthropoids is significantly longer and narrower than in strepsirrhines. This difference is an
effect of clade and is not due to differences in activity pattern or V1 size. New measurements
of V1 volume were also provided in order to reassess V1 size differences between strepsir-
rhines and anthropoids. It was found that for a given lateral geniculate nucleus (LGN)
volume, anthropoids have a significantly larger V1 than strepsirrhines do. This is important
since LGN is the principal source of V1's input. Finally, independent contrasts analysis was
used to examine the scaling of V1 relative to LGN, the rest of cortex, and the rest of the brain.
It was confirmed that V1 scales with positive allometry relative to LGN. A number of possible
explanations for scaling are discussed. V1 scaling may have to do with the tendency of large
brains to be more compartmentalized than small brains, or V1 scaling might reflect the
geometry of information representation. 2004 Wiley-Liss, Inc.
Key words: allometry; horizontal meridian; independent contrasts

  

Source: Allman, John M. - Division of Biology, California Institute of Technology

 

Collections: Biology and Medicine