# HPCT and object recognition

**URL:** <http://discourse.iapct.org/t/hpct-and-object-recognition/4965>\
**Category:** CSG1993\
**Created:** [November 5, 1993, 8:50pm UTC](http://discourse.iapct.org/t/hpct-and-object-recognition/4965 "1993-11-05T20:50:19Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Mark\_William\_Olson](http://discourse.iapct.org/letter_avatar_proxy/v4/letter/m/e95f7d/32.png) [@Mark\_William\_Olson](http://discourse.iapct.org/u/Mark_William_Olson)\
**Post date:** [November 5, 1993, 8:50pm UTC](http://discourse.iapct.org/t/hpct-and-object-recognition/4965/1 "1993-11-05T20:50:19Z")

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I am leading a discussion this week on a paper by G.C Baylis and J.  
Driver (1993). Visual Attention and Objects: Evidence for hierarchical  
coding of Location. JEP/HPP, 19, 451-470. It has relevance to  
questions/criticisms I had a number of months ago for HPCT concerning  
neuroanatomy.

I had said a while ago that HPCT just doesn't fit very well with what we  
know of neuroanatomy. For instance, I mentioned that one visual pathway  
(ventral from V1 to Inferior Temporal) is concerned with object  
recognition--something analogous to the configuration level--while the  
dorsal pathway (from V1 thru MT and parietal regions) was concerned with  
coding spatial location--something analogous to the relationship level.  
These systems are conceptualized as being in parallel.

But the article above reformulates our understanding of these separate  
pathways such that the ventral object recognition pathway (also known as  
the What pathway) lies hierarchically below the paretial spatial pathway  
(the Where pathway). The shift comes in conceptualizing the What pathway  
as a system which encodes the spatial relationships between the contours  
of the object. Hence, the What pathway encodes relationships between the  
oject's contours while the Where pathway encodes relationships between the  
objects themselves.

Baylis and Driver didn't think come up with this theory (I think Marr  
did), but this paper gives good evidence for it. Anyway, it has obvious  
implications for HPCT so I thought I'd mention it to ya all.

Mark Olson  
Neuroscience Program  
University of Illinois  
m-olson@uiuc.edu