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Matthew Ratcliffe - One of the best experts on this subject based on the ideXlab platform.
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Real Hallucinations
The MIT Press, 2018Co-Authors: Matthew RatcliffeAbstract:Real Hallucinations is a philosophical study of the structure of human experience, its vulnerability to disruption, and how its integrity depends on interpersonal relations. It focuses on the beguilingly simple question of how we manage to routinely distinguish between our experiences of perceiving, remembering, imagining, and thinking. This question is addressed via a detailed philosophical study of auditory verbal hallucinations (usually defined as hearing a voice in the absence of a speaker) and thought insertion (somehow experiencing one’s own thoughts as someone else’s). The book shows how thought insertion, and also a substantial proportion of auditory verbal hallucinations, consist of disturbances in the structure of experience and –more specifically - in our sense of the various types of Intentional State, such as believing, perceiving, remembering, and imagining, as distinct from one another. It is further argued that episodic and seemingly localized experiential disturbances such as these usually occur against a backdrop of less pronounced but much wider-ranging alterations in the structure of Intentionality. To do so, the book addresses types of experience associated with trauma, schizophrenia, and profound grief. The outcome of this is a more generally applicable account of how the integrity of human experience, including the most basic sense of self, is inseparable from how we relate to other people and to the social world as a whole.
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Real Hallucinations - Intentionality and Interpersonal Experience
Real Hallucinations, 2017Co-Authors: Matthew RatcliffeAbstract:This chapter addresses several interrelated ways in which other people are implicated in the development, sustenance, and disruption of the modal structure of Intentionality. It first considers some of the roles that relations with others play in shaping perceptual experience, focusing on how the cohesive, anticipatory structure of perceptual experience is interpersonally regulated. After that, it turns to belief, arguing that the structure of belief, the intelligibility of the distinction between what is and is not the case, rests on a more primitive sense of certainty. It then proceeds to develop a more general account of how the sense of being in a given type of Intentional State is largely attributable to its distinctive anticipation-fulfilment profile. All such profiles, it is argued, depend on an overarching pattern of anticipation and fulfilment, in the guise of habitual confidence or certainty. This pattern is inextricable from a certain way of experiencing and relating to other people in general. When the overall anticipation-fulfilment structure of experience is disrupted, the boundaries between Intentional State types become less clear. This renders a person susceptible to more pronounced and localized disruptions, of the kind involved in many delusions and hallucinations.
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Metaphilosophical Conclusion
Real Hallucinations, 2017Co-Authors: Matthew RatcliffeAbstract:This chapter draws the discussion to a close by summarizing and further exploring some philosophical implications of the book’s overall position. Among other things, it addresses the nature of ‘belief’, and argues that this term, even when it is used in a restrictive and technical way, most likely accommodates a range of subtly different kinds of conviction, different ways of taking something to be the case. This applies not only to psychiatric illness, but also more generally. Issues are therefore raised for the practice of philosophy itself. When one is said to believe a philosophical claim, it is not always clear what kind of conviction is involved or, for that matter, which kinds of conviction are appropriate to which kinds of philosophical position. More generally, the structure of Intentionality encompasses a wide range of different Intentional State types and does not respect clear-cut, categorical distinctions between them. These subtleties are masked by certain uses of language, in philosophy and elsewhere. Reliance on univocal notions of ‘belief’, ‘desire’, and the like is thus rendered problematic.
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Real Hallucinations - Schizophrenia and Selfhood
Real Hallucinations, 2017Co-Authors: Matthew RatcliffeAbstract:This chapter introduces some of the central concepts, themes, and issues addressed in the book. First of all, it discusses the concept of ‘minimal self’ and its recent application to schizophrenia and auditory verbal hallucination (AVH). Then it raises the question of whether minimal self includes only the sense of having some kind of experience or, in addition, a more specific sense of the type of Intentional State one is in. A refined account of minimal self is proposed, according to which it centrally involves the latter: a grasp of the modalities of Intentionality. It is further argued that certain anomalous experiences centrally involve disturbances of modal structure. Following this, the chapter considers an alternative account of AVHs, according to which they are diagnostically non-specific, meaningful symptoms of interpersonal trauma. In so doing, it stresses the need to place more emphasis on the interpersonal aspects of psychiatric illness, and shows how minimal self, as conceived of here, could turn out to be both developmentally and constitutively dependent on ways of relating to other people.
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Thought Insertion Clarified
Real Hallucinations, 2017Co-Authors: Matthew RatcliffeAbstract:This chapter begins by considering the possibility that a number of factors contribute to the sense of being in an Intentional State, and that these can come into conflict. The remainder of the chapter argues that thought insertion (TI) and certain kinds of auditory verbal hallucination (AVH) are to be understood in this way. There is a difference between experiencing a process of thinking as alien and experiencing thought content as alien. It is argued that TI involves the latter. Hence it could just as well be described as experiencing one’s own thought contents in a strange, perception-like way. To further support this interpretation, the chapter considers AVHs and shows that a substantial proportion of experiences that are described in AVH terms can equally be conveyed in terms of TI. What we have is an anomalous experience that lies somewhere between thinking and perceiving. The content of the experience continues to resemble that of a thought. Even so, a sense of perceiving predominates. The chapter concludes by arguing that it is unhelpful to conceive of AVH / TI in terms of a distinction between agency and subjectivity or ownership.
Toshihisa Tanaka - One of the best experts on this subject based on the ideXlab platform.
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Asynchronous Brain–Computer Interfacing Based on Mixed-Coded Visual Stimuli
IEEE Transactions on Biomedical Engineering, 2018Co-Authors: Kaori Suefusa, Toshihisa TanakaAbstract:Objective: One of the challenges in the area of brain–computer interfacing (BCI) is to develop an asynchronous BCI or a self-paced BCI that detects whether a user intends to pass messages. This paper proposes a novel asynchronous BCI that uses mixed frequency and phase-coded visual stimuli, which can provide high-speed and accurate command entries. Methods: The mixed-coded visual stimuli were presented as flickers with a following blank interval to synchronize the recorder of electroencephalogram (EEG) with the stimuli, which was aimed to detect the phase in an asynchronous situation. For decoding from the measured EEG, multiset canonical correlation analysis (MCCA) was efficiently exploited for recognizing the Intentional State and the intending command. The proposed asynchronous BCI was tested on 11 healthy subjects. Results: The proposed decoder was capable of discriminating between the Intentional control/noncontrol State and determining the command faster and more accurately than the contrast methods, achieving area under the curve of 0.9191 $\pm$ 0.1206 and command recognition accuracy of 91.08 $\pm$ 13.97 $\%$ with data lengths of 3.0 s. Conclusion: The BCI based on mixed-coded visual stimuli was able to be implemented in an asynchronous manner, and the MCCA-based decoder outperformed the conventional ones in terms of discriminability of Intentional States and command recognition accuracy. Significance: The present study showed that an asynchronous BCI can be implemented with mixed-coded visual stimuli for the first time, which enables a large increase in the number of choices/commands.
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phase based detection of Intentional State for asynchronous brain computer interface
International Conference on Acoustics Speech and Signal Processing, 2015Co-Authors: Kaori Suefusa, Toshihisa TanakaAbstract:An asynchronous brain-computer interface (BCI) is one of the crucial challenges in biomedical signal processing. In asynchronous BCIs, a State when a user does not intend to input commands needs to be distinguished from a State when he/she does. These States are called non-control (NC) State and Intentional control (IC) State respectively. In this paper, a new phase-based method to discriminate between IC/NC States for steady-State visual evoked potential (SSVEP) based asynchronous BCIs is proposed. The method has a two-step tree structure: in the first step, a SSVEP frequency is recognized with canonical correlation analysis (CCA), and in the next step, the State of a user is detected as IC or NC with a classifier such as SVM using phase information. The proposed method was tested on six healthy subjects and has been proved to be reliable in terms of sensitivity and specificity.
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ICASSP - Phase-based detection of Intentional State for asynchronous brain-computer interface
2015 IEEE International Conference on Acoustics Speech and Signal Processing (ICASSP), 2015Co-Authors: Kaori Suefusa, Toshihisa TanakaAbstract:An asynchronous brain-computer interface (BCI) is one of the crucial challenges in biomedical signal processing. In asynchronous BCIs, a State when a user does not intend to input commands needs to be distinguished from a State when he/she does. These States are called non-control (NC) State and Intentional control (IC) State respectively. In this paper, a new phase-based method to discriminate between IC/NC States for steady-State visual evoked potential (SSVEP) based asynchronous BCIs is proposed. The method has a two-step tree structure: in the first step, a SSVEP frequency is recognized with canonical correlation analysis (CCA), and in the next step, the State of a user is detected as IC or NC with a classifier such as SVM using phase information. The proposed method was tested on six healthy subjects and has been proved to be reliable in terms of sensitivity and specificity.
Kaori Suefusa - One of the best experts on this subject based on the ideXlab platform.
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Asynchronous Brain–Computer Interfacing Based on Mixed-Coded Visual Stimuli
IEEE Transactions on Biomedical Engineering, 2018Co-Authors: Kaori Suefusa, Toshihisa TanakaAbstract:Objective: One of the challenges in the area of brain–computer interfacing (BCI) is to develop an asynchronous BCI or a self-paced BCI that detects whether a user intends to pass messages. This paper proposes a novel asynchronous BCI that uses mixed frequency and phase-coded visual stimuli, which can provide high-speed and accurate command entries. Methods: The mixed-coded visual stimuli were presented as flickers with a following blank interval to synchronize the recorder of electroencephalogram (EEG) with the stimuli, which was aimed to detect the phase in an asynchronous situation. For decoding from the measured EEG, multiset canonical correlation analysis (MCCA) was efficiently exploited for recognizing the Intentional State and the intending command. The proposed asynchronous BCI was tested on 11 healthy subjects. Results: The proposed decoder was capable of discriminating between the Intentional control/noncontrol State and determining the command faster and more accurately than the contrast methods, achieving area under the curve of 0.9191 $\pm$ 0.1206 and command recognition accuracy of 91.08 $\pm$ 13.97 $\%$ with data lengths of 3.0 s. Conclusion: The BCI based on mixed-coded visual stimuli was able to be implemented in an asynchronous manner, and the MCCA-based decoder outperformed the conventional ones in terms of discriminability of Intentional States and command recognition accuracy. Significance: The present study showed that an asynchronous BCI can be implemented with mixed-coded visual stimuli for the first time, which enables a large increase in the number of choices/commands.
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phase based detection of Intentional State for asynchronous brain computer interface
International Conference on Acoustics Speech and Signal Processing, 2015Co-Authors: Kaori Suefusa, Toshihisa TanakaAbstract:An asynchronous brain-computer interface (BCI) is one of the crucial challenges in biomedical signal processing. In asynchronous BCIs, a State when a user does not intend to input commands needs to be distinguished from a State when he/she does. These States are called non-control (NC) State and Intentional control (IC) State respectively. In this paper, a new phase-based method to discriminate between IC/NC States for steady-State visual evoked potential (SSVEP) based asynchronous BCIs is proposed. The method has a two-step tree structure: in the first step, a SSVEP frequency is recognized with canonical correlation analysis (CCA), and in the next step, the State of a user is detected as IC or NC with a classifier such as SVM using phase information. The proposed method was tested on six healthy subjects and has been proved to be reliable in terms of sensitivity and specificity.
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ICASSP - Phase-based detection of Intentional State for asynchronous brain-computer interface
2015 IEEE International Conference on Acoustics Speech and Signal Processing (ICASSP), 2015Co-Authors: Kaori Suefusa, Toshihisa TanakaAbstract:An asynchronous brain-computer interface (BCI) is one of the crucial challenges in biomedical signal processing. In asynchronous BCIs, a State when a user does not intend to input commands needs to be distinguished from a State when he/she does. These States are called non-control (NC) State and Intentional control (IC) State respectively. In this paper, a new phase-based method to discriminate between IC/NC States for steady-State visual evoked potential (SSVEP) based asynchronous BCIs is proposed. The method has a two-step tree structure: in the first step, a SSVEP frequency is recognized with canonical correlation analysis (CCA), and in the next step, the State of a user is detected as IC or NC with a classifier such as SVM using phase information. The proposed method was tested on six healthy subjects and has been proved to be reliable in terms of sensitivity and specificity.
John R. Searle - One of the best experts on this subject based on the ideXlab platform.
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Oxford Scholarship Online - Are there Non-Propositional Intentional States?
Oxford Scholarship Online, 2018Co-Authors: John R. SearleAbstract:Intentionality is that feature of the mind by which it is directed at or about objects and States of affairs in the world. Intentionality is simply aboutness or directedness. “Proposition” is more difficult, but the essential idea is this: every Intentional State has a content. Sometimes it seems that the content just enables a State to refer to an object. So if John loves Sally, then it appears that the content of his love is simply “Sally”. But if John believes that it is raining, then the specification of the content requires an entire “that” clause. “Are there non-propositional Intentional States?” amounts to the question, “Are there Intentional States whose content does not require specification with a ‘that’ clause?” This chapter explores whether there are any non-propositional States, and suggest that a very limited class, such as boredom, is in fact non-propositional.
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Reply To B. Jeannie Lum
Searle’s Philosophy and Chinese Philosophy, 2008Co-Authors: John R. SearleAbstract:Jeannie Lum's work exhibits a thorough understanding of both the Chinese and the Western sensibility and a strong sense of the empirical reality of all the issues when applied to real life problems in education. The propositional content of the author's unconscious Intentional State functions causally in producing his behavior, and the same propositional content can be either conscious or unconscious. The unconscious, when unconscious, consists of a set of brain capacities which are in principle capable of turning the unconscious Intentional State into a conscious form. But that makes it look as if unconscious Intentional States, when unconscious, have the ontology of Background abilities. Of course, in actual cases, there may be all sorts of reasons why the unconscious Intentional State is blocked from consciousness, such as brain damage, repression, or simple forgetfulness. Keywords: Intentional States; Jeannie Lum; ontology
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The Connection Principle and the Ontology of the Unconscious: A Reply to Fodor and Lepore
Philosophy and Phenomenological Research, 1994Co-Authors: John R. SearleAbstract:I want to use the occasion of responding to Fodor and Lepore not only to answer their questions but also to enter into a more general discussion of the Connection Principle (CP). Here is a problem in cognitive science that is central to the whole enterprise but is generally neglected: How do we distinguish between the mental and the non-mental? This problem is important to cognitive science for several reasons, but for present purposes, it is especially important because mentalistic explanations have logical properties that other sorts of explanations do not have. Specifically, in mentalistic explanations the actual content of the explanation plays a causal role in the production of the phenomenon to be explained in a way that the content of other explanations does not play any causal role at all. You can see this -by contrasting two cases. If I say that a body falls a certain distance in a certain time because it is an instance of the law, S = 1/2gt2, I give an explanation of the behavior of a falling body by stating a law which has a certain semantic or Intentional content, but the content, S = 1/2gt2, plays no causal role whatever. It simply describes and explains, it does not cause. But if I explain the behavior of a runner by saying that the runner is trying to run a mile in six minutes, then the actual Intentional State present in the agent and specified in the explanation, "trying to run a mile in six minutes", plays a causal role in the production of the behavior, the behavior is precisely one of trying to realize the conditions of satisfaction of that Intentional State. This is a familiar distinction. A special case of the distinction is the familiar one between rule-described and rule-governed or rule-guided behavior. In general, mentalistic explanations are about phenomena that are content-guided, and in particular mentalistic explanations that appeal to rules are about phenomena that are rule-guided, not merely rule-described.
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Intentionality and its Place in Nature
Philosophy Mind and Cognitive Inquiry, 1990Co-Authors: John R. SearleAbstract:Intentionality is that feature of certain mental States and events that consists in their (in a special sense of these words) being directed at, being about, being of, or representing certain other entities and States of affairs. If, for example, Robert has the belief that Ronald Reagan is President, then his belief is an Intentional State because in the appropriate sense his belief is directed at, or about, or of, or represents Ronald Reagan and the State of affairs that Ronald Reagan is President. In such a case Ronald Reagan is the Intentional object of Robert’s belief, and the existence of the State of affairs that Ronald Reagan is President is the condition of satisfaction of his belief. If there is not anything that a belief is about, then it does not have an Intentional object; and if the State of affairs it represents does not obtain, it is not satisfied.
Mark Sainsbury - One of the best experts on this subject based on the ideXlab platform.
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Oxford Scholarship Online - Attitudes on Display
Oxford Scholarship Online, 2018Co-Authors: Mark SainsburyAbstract:Intentional States are representational States, involving the exercise of conceptual structures, which are vehicles of representation. Structures evaluable as true or false are called “thoughts”. We can describe two categories of Intentional States: those involving thoughts, call them “propositional attitudes”, and those not involving thoughts, call them “objectual attitudes”. We can distinguish among attributions of attitudes between those that involve full sentential complements, like “She believes that it will rain today” (call these “sentential attributions”), and those like “She wants rain” which do not (call these “non-sentential attributions”). Are the kinds of attribution fundamentally different? The main claim of the chapter is that they are not. In both kinds of attribution a conceptual structure is put on display, and the attribution is correct just if the displayed structure is suitably related to the structure in the Intentional State of the subject of the attribution.
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Oxford Scholarship Online - Relationality and Representation
Oxford Scholarship Online, 2018Co-Authors: Mark SainsburyAbstract:Thinking about Obama and thinking about Pegasus seem to be the same fundamental kind of thing, yet one is relational and the other not. I address this puzzle by distinguishing various different kinds of relationality. The Obama-thought and the Pegasus-thought are both metaphysically relational in that both thinkers are in States that relate them to representations. The relationality is covert: it is not overtly expressed in attitude attribution, and the second term of the relation is not what the Intentional State is about. Are representations relational? It is natural to think so, because representation is often analyzed by tracking relations that connect the concepts to entities in the world. I argue that we can understand representation in a non-relational way. The upshot is that all Intentional States are relational in that a subject is related to a representation, and some Intentional States have a further dimension of relationality if the relevant representation is a relational one.