E-mails from Patrik Vuilleumier trying to convince me that there is
really evidence for <a href="myths.html#spatial frequency">distinct
channels for processing different spatial frequnecies</a>. It is an
extended example of the "bogus refernce" technique, because he gives
many references, none of which actually supports his claim.

<p>

There are two message from him, in which he included the message 
from me to which he responds. He did not answer my third message. 
<p>
==========================================================<br>
<b>First message </b> <br> 
==========================================================<br>

<pre> 

From: "Patrik Vuilleumier" <patrik.vuilleumier_medecine.unige.ch>
To: "Yehouda Harpaz" <yh@maldoo.com>
Sent: Tuesday, June 10, 2003 9:43 AM
Subject: Re: spatial frequency channels

Hi
You will find information on parvo and magno pathways in virtally any
textbook of neurophysiology or of vision. A classical book iby DeValois
& DeValois
Here a few (arbitray) ref.
Braje, W. L., B. S. Tjan, et al. (1995). "Human efficiency for
recognizing and detecting low-pass filtered objects." Vision Res
35(21): 2955-66.
Brogan, D. (1985). "Spatial frequency range in the detection
process--1. Narrow bars." Ophthalmic Physiol Opt 5(2): 125-35.
Burbeck, C. A. (1987). "Position and spatial frequency in large-scale
localization judgments." Vision Res 27(3): 417-27.
Costen, N. P., D. M. Parker, et al. (1994). "Spatial content and
spatial quantisation effects in face recognition." Perception 23(2):
129-46.
Costen, N. P., D. M. Parker, et al. (1996). "Effects of high-pass and
low-pass spatial filtering on face identification." Percept Psychophys
58(4): 602-12.
Grounds, A. R., I. E. Holliday, et al. (1983). "Two spatio-temporal
filters in human vision. 2. Selective modification in amblyopia,
albinism, and hemianopia." Biol Cybern 47(3): 191-201.
Hammett, S. T. and A. T. Smith (1992). "Two temporal channels or three?
A re-evaluation." Vision Res 32(2): 285-91.
Julesz, B. (1975). "Two-dimensional spatial-frequency-tuned channels in
visual perception. pp. 177-97." In: Inbar GF, ed. Signal analysis and
pattern recognition in biomedical engineering. New York, Wiley.
Moscovitch, M. and M. Radzins (1987). "Backward masking of lateralized
faces by noise, pattern, and spatial frequency." Brain Cogn 6(1): 72-90.
Snowden, R. J. (1992). "Orientation bandwidth: the effect of spatial
and temporal frequency." Vision Res 32(10): 1965-74.
PV

On Dimanche, juin 8, 2003, at 14:36 Europe/Zurich, Yehouda Harpaz wrote:

> Dear Patrik Vuilleumier,
>
> In your articl in Nature Neuroscience (Distinct spatial frequency
> sensitivities
> for processing faces and emotional expressions, June 2003 Volume 6
> Number 6 pp 624 - 631), you write:
>
>
>
>    "High and low spatial frequency information in visual images is
>      processed by distinct neural channels."
>
> Can you give some references for that?
>
> Thanks,
>
> Yehouda Harpaz
>
>
</pre>

===============================================================<br>
<b>Second message </b><br>
===============================================================<br>

<pre>
From: "Patrik Vuilleumier" <patrik.vuilleumier_medecine.unige.ch>
To: "yehouda harpaz" <yh@maldoo.com>
Sent: Friday, June 13, 2003 3:59 PM
Subject: Re: spatial frequency channels


I can assure you there are many writings, see De Valois but also Merigan, W.
H.
Maunsell, J. H., and books by Milner and Goodale, or by Ivry and
Roberstson for reviews. but maybe your views of what is a "channel" is
different
pv

On Jeudi, juin 12, 2003, at 22:35 Europe/Zurich, yehouda harpaz wrote:





Hi,


> >You will find information on parvo and magno pathways in virtally any
> > textbook of neurophysiology or of vision.


> I didn't remember any association betwen the P, M , K pathways and
> spatial frequency, but since you wrote with such confidence I went
> and checked some of the latest textbooks. None of them mentions anything
> like distinct channels for spatial frequency beyond the LGN, whether
> in conjunction with the P,M,K pathways or not.
> There are some cursory referneces to evidence of different sensitivity
> to spatial frequency in the LGN itself, and maybe that what you mean.
> However, your statement is about processing of information in visual
> images, which is done mostly in the cortex, so your statement as is,
without
> qualifying it to the LGN only, is false according to the textbooks.


> > A classical book by DeValois & DeValois
> >Here a few (arbitray) ref.


> The Devalois's book is available here only in the central library, which
> is inconvenient for me. Do they actually bring evidence for distinct
> channels in the cortex? If so, why does everybody else ignore it?
> The arbitrary references seem all to be behavioural rather than
> anatomical. Does any of them really brings anatomical evidence
> for distinct channels? which one?

> Thanks,

> Yehouda Harpaz
</pre> 


===============================================================<br>
<b>My response to his second message, which he didn't answer</b><br>
===============================================================<br> 

<pre> 
From: "yehouda harpaz" <yh_maldoo.com>
To: "Patrik Vuilleumier" <patrik.vuilleumier_medecine.unige.ch>
Sent: Saturday, June 14, 2003 9:34 PM
Subject: Re: spatial frequency channels


> I can assure you there are many writings, see De Valois but also
> Merigan, W. H.
> Maunsell, J. H., and books by Milner and Goodale, or by Ivry and
> Roberstson for reviews.

I have now check the De valios's book, Ivry & Robertson and
Milner & Goodale. None of them quote any evidence for distinct
channels for spatial frequency beyond the LGN. In The De Valois's,
Plant (pp. 43-63) first quote the evidence about the LGN, and then
go on to interpret behavioural evidence and from brain damage as
supporting such channels in later stages. Ivry and Robertson don't
give any anatomical evidence. Milner and Goodale also quote only
evidence about the LGN. In p. 134 they give a comment from which
it may seem that the distinction of channels for spatial frequency also
exist in the V1, but this is not based on evidence.

> but maybe your views of what is a "channel" is different

If it is a linguistic difference, it is the difference in the understanding
of  the phrase "distinct channel".

Another possible difference is what we consider evidence. The bulk of
the evidence you quoted is behavioural, and maybe you believe that this
really can tell us anything about the structure inside, even when it
contradicts the anatomical evidence.

</pre>