Why would you assume that the decussation of projections from retinal
ganglion cells in the pyramidal tract have different origins than
those of the optic tract? Don't they have a common origin in the
retina?
rlh
>>>[Hammond]
>This is a very powerful line of analysis. The situation
>certainly is complex. For instance, there are two major
>decussations in optical-motor response. One in the decussation
>of the optic tract, and the other in the decussation of the
>pyramidal tracts. I would suppose they have different origins.
>the optic decussation is probably to nullify the lens inversion,
>but the (more massive) pyramidal decussation may be something along
>the lines you describe. Also, the fornix has a suspicious
>congruence with the optic chiasma which would have to be analyzed.
>>>>> Filip van den Bergh
>>>> Badly drawn figures (best viewed in courier font)
>> S = sensory unit
>> M = motor unit
>> | = straight connection
>> X = crossed connection
>>>> Figure A
>>>> S1 S2
>> | |
>> M1 M2
>>>> Figure B
>>>> S1 S2
>> X
>> M1 M2
>>--
>BE SURE TO VISIT MY WEBSITE, BELOW:
>-----------------------------------------------------------
>George Hammond, M.S. Physics
>Email: ghammond at mediaone.net>Website: http://people.ne.mediaone.net/ghammond/index.html>-----------------------------------------------------------
--
Richard L. Hall, Ph.D.
Comparative Animal Physiologist
University of the Virgin Islands
2 John Brewers Bay
St. Thomas, U.S.V.I. 00802
340-693-1386
340-693-1385 FAX
rhall at uvi.edu
"Live life on the edge...the view is always better" rlh
---