A Legion of Lesions: The Neuroscientific Rout of Higher-Order Thought Theory

Abstract

Higher-order thought (HOT) theory says that a mental state is conscious when and only when represented by a conceptual, belief-like mental state. Plausibly, HOT theory predicts the impairment of HOT-producing brain areas to cause significant deficits in consciousness. This means that HOT theory can be refuted by identifying those brain areas that are candidates for producing HOTs, then showing that damage to these areas never produces the expected deficits of consciousness. Building this refutation is a work-in-progress, with several key components of it already existing in the literature (e.g.,

An embarrassment of richnesses: the PFC isn’t the content NCC

“…Because of the kind of cognitive complexity such states involve, the PFC is the most likely place to produce HOTs ( Lau and Rosenthal 2011 , Lau 2011 ; see esp. Kozuch 2023 ; but see Gennaro 2012 ), and if this is true, then PFC Theory and HOT Theory would be allied. But consider now a well-known objection to HOT theory, one that we can call the “Problem of the Misrepresenting HOT” ( Neander 1998 ; Block 2011 ).…”

“…This ‘PFC Theory’ has been met with many early empirical successes, ones coming from numerous correlations found between visual experience and PFC activity (for review: Michel 2022 ). On the other hand, such evidence can be accounted for without hypothesizing the PFC to be essential for consciousness ( Kozuch 2014 ; Pitts et al 2014 ; but see Michel and Morales, 2020 ), and PFC Theorists have difficulty explaining why the PFC can be severely damaged without equally severe deficits in consciousness appearing ( Pollen 1999 , 2007 ; Kozuch 2014 , 2021 , 2023 , Boly et al. 2017 ; but see Odegaard et al.…”

“…2017 , Knotts et al. 2018 , Kozuch 2021 , 2023 ). Even researchers who argue against visual experience actually being rich in this way agree that it at least ‘appears’ rich ( Cohen et al.…”

“…2017 , Knotts et al. 2018 , Kozuch 2021 , 2023 ). For example, if we examine the visual experience that one has when standing on the beach, facing the ocean, it might look as follows: throughout one large, lower part of the visual field, the color of the sand is represented, interrupted only by the colors of the surfaces of whatever objects are located there; a little higher in the visual field, one finds the color of the water, its translucent green punctuated by the white of the foam of its breaking waves; in another part one finds the blue of the sky, interrupted by whiteness where clouds are located; and so on.…”