Place, U. T. (1998h). The neuroanatomy of consciousness and the zombie-within. [Paper presented at the Second Annual Conference of the Association for the Scientific Study of Consciousness, Bremen, Germany, 20th June 1998].
[Abstract]In Chapter 3 of their book, Milner & Goodale (1995) concede that, since the ventral and dorsal streams as defined by Ungerleider & Mishkin (1982) bifurcate "downstream" of the striate cortex (V1), neither stream can account for the visual functions which survive lesions of V1 ("blindsight"). However, on their Figure 3.1 (p. 68) they show another pathway which I call the 'Sub-Cortical (S-C) to dorsal pathway' (SUPERIOR COLLICULUS, PULVINAR, POSTERIOR PARIETAL CORTEX) which bifurcates from the ventral pathway (LATERAL GENICULATE NUCLEUS, V1-V5, INFERO-TEMPORAL CORTEX) at the retina. Not only does the S-C to dorsal pathway explain blindsight. It also coincides exactly with Michael Posner's (Posner & Petersen 1990; Posner and Dehaene 1994) "posterior attention system". This allows us to identify the superior colliculus and pulvinar with that part of the "zombie-within" (Place 1997) which involuntarily attracts the focus of conscious attention to any input which it identifies as problematic and the posterior parietal cortex as the structure which, in addition to its role in the feedback control of voluntary movement, maintains voluntary control over the focus of conscious attention (in the ventral stream in the case of vision) until a satisfactory categorization of the input is achieved. This, when combined with the known functions of the ventral pathway, allows us, in the case of vision, to identify actual anatomically defined structures corresponding to most of the functionally defined modules envisaged in 'Consciousness and the zombie-within' (Place 1997) up to the point where conscious experience gives way to categorization.
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Download: 1998h The Neuroanatomy of Consciousness and the Zombie-within.pdf