Dear Hoover:
Could you please post this onto CVNET. Thank you in advance.
Silvio
-----
A large amount of data reported on the well-known spatial arrangement of
orientation preference in striate visual areas [1][2][3].
A similar columnar organization was observed also for direction selectivity
[8][14]. Recently, by optical imaging techniques, dense maps were
obtained pointing out relationships between orientation and direction
selectivities in striate cortex [4][5][13].
Moreover, spatial arrangements of directionality in extrastriate areas (MT
and MST) were observed suggesting their possible role in global optic flow
processing [6][7][9][10][11][12].
I'm carrying on my post-doc research on the cortical bases of motion
perception. In particular, I'm presently considering the computational
role of striate and extrastriate mappings of motion parameters (orientation,
direction, velocity), in the perception and interpretation of motion cues.
In order to make biologically plausible simulations I'm seeking data on real
maps.
Can anyone please suggest where I can find the following kind of information?
1) Are there available rough data files (i.e., angles) related to dense
direction selectivity in the striate cortex? ^^^^^
(I tried to `decode' data from the hue of scanned color maps [4][5], but I
didn't succeeded)
2) Are there similar data files for the organization of direction preferences
in extrastriate areas?
3) How are different velocities arranged within a direction preference column in
the striate cortex?
4) Could you please provide me any pointer on experimental evidence for
dense velocity maps in area MT (and MST).
(the only reference I got is [15])
5) Considering W_x and W_t the spatial and temporal frequency of a simple
cell in primary visual cortex, respectively
Are there available data on conjoint (W_x, W_t) maps?
I thank you in advance for any advice.
--Silvio Sabatini (silvio@dibe.unige.it)
PSPC Research Group
DIBE - University of Genova |
Via Opera Pia, 11A | voice: +39 10 3532289/3532794
I-16145 Genova (ITALY) | fax: +39 10 3532795/3532777
URL: http://dibe.unige.it/department/micro/pspc/home.html
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