Higher Order Thought and the Problem of Radical Confabulation

Currently, one of the most influential theories of consciousness is Rosenthal's version of higher-order-thought (HOT). We argue that the HOT theory allows for two distinct interpretations: a one-component and a two-component view. We further argue that the two-component view is more consistent with his effort to promote HOT as an explanatory theory suitable for application to the empirical sciences. Unfortunately, the two-component view seems incapable of handling a group of counterexamples that we refer to as cases of radical confabulation. We begin by introducing the HOT theory and by indicating why we believe it is open to distinct interpretations. We then proceed to show that it is incapable of handling cases of radical confabulation. Finally, in the course of considering various possible responses to our position, we show that adoption of a disjunctive strategy, one that would countenance both one-component and two-component versions, would fail to provide any empirical or explanatory advantage

Mental Ownership and Higher Order Thought

Mental ownership concerns who experiences a mental state. According to David Rosenthal (2005: 342), the proper way to characterize mental ownership is: ‘being conscious of a state as present is being conscious of it as belonging to somebody. And being conscious of a state as belonging to somebody other than oneself would plainly not make it a conscious state’. In other words, if a mental state is consciously present to a subject in virtue of a higher-order thought (HOT), then the HOT necessarily representsthe subject as the owner of the state. But, we contend, one of the lessons to be learned from pathological states like somatoparaphrenia is that conscious awareness of a mental state does not guarantee first-person ownership. That is to say, conscious presence does not imply mental ownership

Self-as-subject and experiential ownership

In what follows, I investigate the distinction between the sense of self-as-object and the sense of self-as-subject, and propose an account that is different from Shoemaker’s immunity principle. I suggest that this distinction can be elucidated by examining two types of self-experience: the sense of body ownership and the sense of experiential ownership. The former concerns self-as-object: whether a body part or a full body belongs to me. The latter concerns self-as-subject: whether I represent myself as the unique subject of experience. A key point is that misrepresentation can occur not only in the sense of body ownership but also in the sense of experiential ownership. Then I examine the most relevant neuroscientific accounts of the sense of self-as-subject, including Damasio’s account of the core-self, Panksepp’s affective neuroscience, neural synchrony, and the subcortical-cortical midline structures. I argue that none of these successfully explains the neural basis of the sense of self-as-subject. In order to make progress, I suggest, the first step is to look for and then to study the various conditions in which one can pursue the “Wittgenstein Question”

Can experiential ownership violate the immunity principle? : A reply to Oliver Haug & Marius F. Jung

In what follows, I respond to Haug and Jung’s criticisms of my target paper and defend the following claims: (1) the sense of experiential ownership can misrepresent the fact of experiential ownership; (2) the sense of experiential ownership is eligible to serve as a bearer of IEM; (3) at least some versions of IEM face genuine counterexamples; and (4) as far as the sense of self-as-subject is concerned, IEM is not a trivial property. Finally, I describe a new set of experiments that induced what I call “the self-touching illusion.” The data, I suggest, strengthen the view that both the sense of self-as-subject and IEM are open to empirical as well as philosophical investigation

Self-Consciousness and Immunity

Sydney Shoemaker, developing an idea of Wittgenstein’s, argues that we are immune to error through misidentification relative to the first-person pronoun. Although we might be liable to error when “I” (or its cognates) is used as an object, we are immune to error when “I” is used as a subject (as when one says, “I have a toothache”). Shoemaker claims that the relationship between “I” as-subject and the mental states of which it is introspectively aware is tautological: when, say, we judge that “I feel pain,” we are tautologically aware that feels pain is instantiated and that it is instantiated in oneself. Moreover, he contends that this relationship holds not just for bodily sensations, but also for the sense of agency and for visual perception. But we deny that this relationship is tautological; instead, we treat Shoemaker’s principle (IEM) as a hypothesis. We then proceed to show that certain pathological states and experimentally-induced illusions can be adduced to show that IEM describes not a necessary relationship but a contingent relationship, one that sometimes fails to obtain. That we are not immune to error in the way Shoemaker describes has grave consequences for many aspects of his ideas concerning the first-person perspective. In the course of arguing that these empirical phenomena count against IEM, we also show that not only can the content of conscious experience be misrepresented, so too can the subject: that is, not only can the what of conscious experience be misrepresented, so too can the who

Curl-free ray mapping in three dimensions for freeform illumination design

An illumination design method that incorporates the entire 3-D geometry between the optical surface and target plane into the ray mapping calculation has been developed. The resulting mapping relationship is integrable along the specific contours of the optical surface instead of a 2-D plane. The method is capable of creating extremely high performance, off-axis designs (97% uniformity at 54-deg off-axis), and since it explicitly accounts for system geometry, appears to be easily generalizable. (C) 2019 Society of Photo-Optical Instrumentation Engineers (SPIE)National Institute of Biomedical Imaging and Bioengineering of the National Institutes of Health [UH2EB022623]; National Science Foundation Graduate Research Fellowship [DGE-1746060]This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Body-as-Subject in the Four-Hand Illusion

In a recent study (Chen et al., 2018), we conducted a series of experiments that induced the “four-hand illusion”: using a head-mounted display (HMD), the participant adopted the experimenter's first-person perspective (1PP) as if it was his/her own 1PP. The participant saw four hands via the HMD: the experimenter's two hands from the adopted 1PP and the subject's own two hands from the adopted third-person perspective (3PP). In the active four-hand condition, the participant tapped his/her index fingers, imitated by the experimenter. Once all four hands acted synchronously and received synchronous tactile stimulations at the same time, many participants felt as if they owned two more hands. In this paper, we argue that there is a philosophical implication of this novel illusion. According to Merleau-Ponty (1945/1962) and Legrand (2010), one can experience one's own body or body-part either as-object or as-subject but cannot experience it as both simultaneously, i.e., these two experiences are mutually exclusive. Call this view the Experiential Exclusion Thesis. We contend that a key component of the four-hand illusion—the subjective experience of the 1PP-hands that involved both “kinesthetic sense of movement” and “visual sense of movement” (the movement that the participant sees via the HMD)—provides an important counter-example against this thesis. We argue that it is possible for a healthy subject to experience the same body-part both as-subject and as-object simultaneously. Our goal is not to annihilate the distinction between body-as-object and body-as-subject, but to show that it is not as rigid as suggested by the phenomenologists