How do we know that our own actions belong to us? How are we able to distinguish self-generated sensory events from those that arise externally? In this paper, I will briefly discuss experiments that were designed to investigate these questions. In particularly, I will review psychophysical and neuroimaging studies that have investigated how we recognise the consequences of our own actions, and why patients with delusions of control confuse self-produced and externally produced actions and sensations. Studies investigating the failure of (...) this 'self-monitoring' mechanism in patients with delusions of control will be discussed in the context of the hypothesis that overactivity in the parietal cortex and the cerebellum contribute to the misattribution of an action to an external source (). (shrink)

In this paper, I investigate in detail one theoretical approach to the symptom of thought insertion. This approach suggests that patients are lead to disown certain thoughts they are subjected to because they lack a sense of active participation in the occurrence of those thoughts. I examine one reading of this claim, according to which the patients’ anomalous experiences arise from a breakdown of cognitive mechanisms tracking the production of occurrent thoughts, before sketching an alternative reading, according to which their (...) experiences have to be explained in terms of a withdrawal, on the part of the patients themselves, from certain forms of active engagement in reasoning. I conclude with a discussion of the relationship between this view and the idea that patients’ reports of thought insertion reflect a situation in which the boundaries between the self and the world have become uncertain. (shrink)

A popular approach to monothematic delusions in the recent literature has been to argue that monothematic delusions involve broadly rational responses to highly unusual experiences. Campbell calls this the empiricist approach to monothematic delusions, and argues that it cannot account for the links between meaning and rationality. In place of empiricism Campbell offers a rationalist account of monothematic delusions, according to which delusional beliefs are understood as Wittgensteinian framework propositions. We argue that neither Campbell's attack on empiricism nor his rationalist (...) alternative to empiricism is successful. (shrink)

In this paper we defend the doxastic conception of delusions against the metacognitive account developed by Greg Currie and collaborators. According to the metacognitive model, delusions are imaginings that are misidentified by their subjects as beliefs: the Capgras patient, for instance, does not believe that his wife has been replaced by a robot, instead, he merely imagines that she has, and mistakes this imagining for a belief. We argue that the metacognitive account is untenable, and that the traditional conception of (...) delusions as beliefs should be retained. (shrink)

John Campbell (1999) has recently maintained that the phenomenon of thought insertion as it is manifested in schizophrenic patients should be described as a case in which the subject is introspectively aware of a certain thought and yet she is wrong in identifying whose thought it is. Hence, according to Campbell, the phenomenon of thought insertion might be taken as a counterexample to the view that introspection-based mental selfascriptions are logically immune to error through misidentification (IEM, hereafter). Thus, if Campbell (...) is right, it would not be true that when the subject makes a mental self-ascription on the basis of introspective awareness of a given mental state, there is no possible world in which she could be wrong as to whether it is really she who has that mental state. Notice the interesting interdisciplinary implications of Campbell’s project: on the one hand, a fairly precise notion elaborated in philosophy such as IEM (and the related notion of error through misidentification, EM hereafter) is used to describe a characteristic symptom of schizophrenia.1 On the other hand, such a phenomenon, described in the way proposed, is taken to be a possible counterexample to a sort of “philosophical dogma” such as IEM of introspection-based non-inferential mental self-ascriptions. In the first section of the paper I will point out the characteristic features of EM and explain logical immunity to error through misidentification of introspection-based mental self-ascriptions; in the second section I will consider the case of thought insertion in more detail and show why, after all, it is not a counterexample to the view that introspectionbased mental self-ascriptions are logically IEM. Finally, I will offer a re-description of the phenomenon of thought insertion. (shrink)

Chris Frith has argued that a loss of the sense of agency is central to schizophrenia. This suggests a connection between hallucinations and delusions on the one hand, and the misidentification of the subject’s imaginings as perceptions and beliefs on the other. In particular, understanding the mechanisms that underlie imagination may help us to explain the puzzling phenomena of thought insertion and withdrawal. Frith sometimes states his argument in terms of a loss of metarepresentational capacity in schizophrenia. I argue that (...) this formulation is unhelpful. (shrink)

What is involved in the consciousness of a conscious, "occurrent" propositional attitude, such as a thought, a sudden conjecture or a conscious decision? And what is the relation of such consciousness to attention? I hope the intrinsic interest of these questions provides sufficient motivation to allow me to start by addressing them. We will not have a full understanding either of consciousness in general, nor of attention in general, until we have answers to these questions. I think there are constitutive (...) features of these states which can be identified by broadly philosophical investigation, and in the early part of this paper I will try to do some of that identification. -/- Beyond the intrinsic interest of the topic, the nature of such conscious attitudes is highly pertinent to a philosophical account of psychological self-knowledge. So I will also say something about the significance of the constitutive features of these conscious attitudes for a philosophical account of how it can be that a thinker has a distinctive kind of knowledge of some of his mental states. The general challenge in this area is to find anything intermediate between the unexceptionable but uninformative, on the one hand, and the absolutely unbelievable on the other. (shrink)

The Capgras delusion is a condition in which a person believes that an imposter has replaced some close friend or relative. Recent theorists have appealed to Bayesianism to help explain both why a subject with the Capgras delusion adopts this delusional belief and why it persists despite counter-evidence. The Bayesian approach is useful for addressing these questions; however, the main proposal of this essay is that Capgras subjects also have a delusional conception of epistemic possibility, more specifically, they think more (...) things are possible, given what is known, than non-delusional subjects do. I argue that this is a central way in which their thinking departs from ordinary cognition and that it cannot be characterized in Bayesian terms. Thus, in order to fully understand the cognitive processing involved in the Capgras delusion, we must move beyond Bayesianism. 1 The Simple Bayesian Model2 Anomalous Evidence and the Capgras Delusion3 Impaired Reasoning4 Setting Priors5 Epistemic Modality6 Delusions of Possibility7 Delusions of Possibility in Different Contexts8 How Many Factors? (shrink)

Article copyright 2002. We provide a battery of examples of delusions against which theoretical accounts can be tested. Then we identify neuropsychological anomalies that could produce the unusual experiences that may lead, in turn, to the delusions in our battery. However, we argue against Maher's view that delusions are false beliefs that arise as normal responses to anomalous experiences. We propose, instead, that a second factor is required to account for the transition from unusual experience to delusional belief. The second (...) factor in the etiology of delusions can be described superficially as a loss of the ability to reject a candidate for belief on the grounds of its implausibility and its inconsistency with everything else that the patient knows, but we point out some problems that confront any attempt to say more about the nature of this second factor. (shrink)

A dominant view in contemporary cognitive neuroscience is that low-level, comparator-based mechanisms of motor control produce a distinctive experience often called the feeling of agency . An opposing view is that comparator-based motor control is largely non-conscious and not associated with any particular type of distinctive phenomenology . In this paper, I critically evaluate the nature of the empirical evidence researchers commonly take to support FoA-hypothesis. The aim of this paper is not only to scrutinize the FoA-hypothesis and data supposed (...) to support it; it is equally to argue that experimentalists supporting the FoA-hypothesis fail to establish that the experimental outcomes are more probable given the FoA-hypothesis than given the simpler hypothesis. (shrink)

I compare Frith and colleagues’ influential comparator account of how the sense of agency is elicited to the multifactorial weighting model advocated by Synofzik and colleagues. I defend the comparator model from the common objection that the actual sensory consequences of action are not needed to elicit the sense of agency. I examine the comparator model’s ability to explain the performance of healthy subjects and those suffering from delusions of alien control on various self-attribution tasks. It transpires that the comparator (...) model needs case-by-case adjustment to deal with problematic data. In response to this, the multifactorial weighting model of Synofzik and colleagues is introduced. Although this model is incomplete, it is more naturally constrained by the cases that are problematic for the comparator model. However, this model may be untestable. I conclude that currently the comparator model approach has stronger support than the multifactorial weighting model approach. (shrink)

There is an increasing amount of empirical work investigating the sense of agency, i.e. the registration that we are the initiators of our own actions. Many studies try to relate the sense of agency to an internal feed-forward mechanism, called the ‘‘comparator model’’. In this paper, we draw a sharp distinction between a non-conceptual level of feeling of agency and a conceptual level of judgement of agency. By analyzing recent empirical studies, we show that the comparator model is not able (...) to explain either. Rather, we argue for a two-step account: a multifactorial weighting process of different agency indicators accounts for the feeling of agency, which is, in a second step, further processed by conceptual modules to form an attribution judgement. This new framework is then applied to disruptions of agency in schizophrenia, for which the comparator model also fails. Two further extensions are discussed: We show that the comparator model can neither be extended to account for the sense of ownership (which also has to be differentiated into a feeling and a judgement of ownership) nor for the sense of agency for thoughts. Our framework, however, is able to provide a unified account for the sense of agency for both actions and thoughts. (shrink)

Brains, it has recently been argued, are essentially prediction machines. They are bundles of cells that support perception and action by constantly attempting to match incoming sensory inputs with top-down expectations or predictions. This is achieved using a hierarchical generative model that aims to minimize prediction error within a bidirectional cascade of cortical processing. Such accounts offer a unifying model of perception and action, illuminate the functional role of attention, and may neatly capture the special contribution of cortical processing to (...) adaptive success. This target article critically examines this approach, concluding that it offers the best clue yet to the shape of a unified science of mind and action. Sections 1 and 2 lay out the key elements and implications of the approach. Section 3 explores a variety of pitfalls and challenges, spanning the evidential, the methodological, and the more properly conceptual. The paper ends (sections 4 and 5) by asking how such approaches might impact our more general vision of mind, experience, and agency. (shrink)

Patients with delusions of control are abnormally aware of the sensory consequences of their actions and have difficulty with on-line corrections of movement. As a result they do not feel in control of their movements. At the same time they are strongly aware of the action being intentional. This leads them to believe that their actions are being controlled by an external agent. In contrast, the normal mark of the self in action is that we have very little experience of (...) it. Most of the time we are not aware of the sensory consequences of our actions or of the various subtle corrections that we make during the course of goal-directed actions. We know that we are agents and that we are successfully causing the world to change. But as actors we move through the world like shadows glimpsed only occasional from the corner of an eye. (shrink)

Ordinarily, if you say something like “I see a comet,” you might make a mistake about whether it is a comet that you see, but you could not be right about whether it is a comet but wrong about who is seeing it. There cannot be an “error of identification” in this case. In making a judgement like, “I see a comet,” there are not two steps, finding out who is seeing the thing and finding out what it is that (...) is being seen, so that you could go wrong at either step. The only place to go wrong is in your description of what is being seen. We usually take it that the same point applies to present-tense ascriptions to oneself of psychological states in general. You can get it wrong about which psychological state you are in, but you cannot get it right about the psychological state but wrong about whose psychological state it is. In contrast, in a room full of people, I might hear a noise and conclude, “Bill sneezed,” and in this case I could be wrong either about who it was that sneezed or about whether it was a sneeze, rather than say a death-rattle. (shrink)

In this paper we defend the doxastic conception of delusions against the metacognitive account developed by Greg Currie and collaborators. According to the metacognitive model, delusions are imaginings that are misidentified by their subjects as beliefs: the Capgras patient, for instance, does not believe that his wife has been replaced by a robot, instead, he merely imagines that she has, and mistakes this imagining for a belief. We argue that the metacognitive account is untenable, and that the traditional conception of (...) delusions as beliefs should be retained. (shrink)

Experiences of thought-insertion are a first-rank, diagnostically central symptom of schizophrenia. Schizophrenic patients who undergo such delusional mental states report being first-personally aware of an occurrent conscious thought which is not theirs, but which belongs to an external cognitive agent. Patients seem to be right about what they are thinking but mistaken about who is doing the thinking. It is notoriously difficult to make sense of such delusions. One general approach to explaining the etiology of monothematic delusions has come to (...) be known as the endorsement model. This model claims that the patient holds her delusional belief because she simply trusts her bizarre experience and takes it at face value. The content of the bizarre experience thus plays a central role in the etiology of delusions. Despite being widely discussed with respect to delusions like Capgras and Cotard, an endorsement model of thought-insertion has not yet been formulated. This article seeks to fill this void by fleshing out and defending the endorsement approach to delusions of inserted thoughts. It aims to show that such an approach can be defended against objections that have been raised in the literature. In particular, it will be argued that there is nothing wrong with the idea of being first-personally aware of a thought which is presented in consciousness as being someone else's. The upshot is that with respect to delusions of thought-insertion, the endorsement model turns out to be a viable account of why patients come to believe that someone else is inserting thoughts into their minds. (shrink)

Over the last 20 years the comparator model for delusions of control has received considerable support in terms of empirical studies. However, the original version clearly needs to be replaced by a model with a much greater degree of sophistication and specificity. Future developments are likely to involve the specification of the role of dopamine in the model and a generalisation of its explanatory power to the whole range of positive symptoms. However, we will still need to explain why symptoms (...) can be so variable and we still do not understand the origin of the most mysterious symptom of all: thought insertion. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Philosophy, Psychiatry, & Psychology 9.1 (2002) 35-39 [Access article in PDF] The Ownership of Thoughts John Campbell Keywords: schizophrenia, thought insertion, immunity to error through misidentification. SYDNEY SHOEMAKER FORMULATED a basic point about first-person, present-tense ascriptions of psychological states when he declared that they are, in general, immune to error through misidentification (Shoemaker 1984). Assuming Shoemaker's point to be correct, the puzzle it raises is this: how are we (...) to explain this datum? Why should it be that first-person, present-tense ascriptions of psychological states are immune to error through misidentification? One type of explanation is in terms of the meaning of the first person: that "I" just stands for whoever is the owner of these (demonstrated) psychological states (including any states being self-ascribed). I argued against this account of the first person in a number of places, and in favor of an alternative explanation of Shoemaker's datum. On the alternative explanation, the reason for the immunity is provided by an account of the ownership of psychological states, on which what makes a psychological state mine is the possibility of self-ascription of it by me (Campbell 1986, 1999a). Suppose we call this the Introspectionist explanation of the immunity to error through misidentification of present-tense self-ascriptions of psychological states. I do think, though, that the simple Introspectionist account is too simple an account of Shoemaker's datum (Campbell 1999a, 1999b). The reason is that there is a certain complexity in our notion of the ownership of a token thought. We cannot give a full account of our ordinary notion of the ownership of a thought simply in terms of the person who is capable of introspective knowledge of the thought. The reason is that there is another dimension to our ordinary notion of the ownership of a thought. We also think of the possessor of a thought as being the person who generated that very thought; we think of the owner of the thought as being the person who brought that particular token thought into existence, the person who formed it. Of course, that token thought may be a copying of someone else's idea; that other person may have influenced my formation of that particular thought. But the point remains that I play a special role in the production of my thoughts.Suppose we have a document bearing a signature and we ask, "Whose signature is that?" In this case we are asking about the authorship of the signature; we are asking who made those particular marks on that bit of paper. Of course, someone else can copy my signature, trying to make it look as if what they write was written by me. But for a particular piece of writing to be an authentic signature of mine, the thing has to be generated by me personally. I think it is helpful to bear in mind this aspect of the notion of the ownership of a signature, when we consider a certain complexity in the notion of the ownership of a thought—I mean, an occurrent, episodic [End Page 35] thought. There are, I am saying, two strands in the ordinary notion of the ownership of a thought, which we do not ordinarily have any reason to separate. First, there is the notion of the person who generated that particular thought, which we might think of on the model of the person who inscribed a particular signature. Of course, in generating a particular token thought, you may be subject to all sorts of influences. Perhaps your thought is derivative, largely shaped by others. Perhaps your thoughts are sometimes simply echoes of the things other people have said. Nonetheless, when we consider how your individual token thoughts are being brought about, you play a proximal role in their formation that no one else does. To give an analogy, suppose that I am taking notes at your dictation. Then there is a sense in which the contents of my notes are entirely determined by you. But there is also a sense in which the token sentences are being generated by... (shrink)

Chris Frith has argued that a loss of the sense of agency is central to schizophrenia. This suggests a connection between hallucinations and delusions on the one hand, and the misidentification of the subject’s imaginings as perceptions and beliefs on the other. In particular, understanding the mechanisms that underlie imagination may help us to explain the puzzling phenomena of thought insertion and withdrawal. Frith sometimes states his argument in terms of a loss of metarepresentational capacity in schizophrenia. I argue that (...) this formulation is unhelpful. (shrink)

Circumscribed delusional beliefs can follow brain injury. We suggest that these involve anomalous perceptual experiences created by a deficit to the person's perceptual system, and misinterpretation of these experiences due to biased reasoning. We use the Capgras delusion (the claim that one or more of one's close relatives has been replaced by an exact replica or impostor) to illustrate this argument. Our account maintains that people voicing this delusion suffer an impairment that leads to faces being perceived as drained of (...) their normal affective significance, and an additional reasoning bias that leads them to put greater weight on forming beliefs that are observationally adequate rather than beliefs that are a conservative extension of their existing stock. We show how this position can integrate issues involved in the philosophy and psychology of belief, and examine the scope for mutually beneficial interaction. (shrink)

How do we know that our own actions belong to us? How are we able to distinguish self-generated sensory events from those that arise externally? In this paper, I will briefly discuss experiments that were designed to investigate these questions. In particularly, I will review psychophysical and neuroimaging studies that have investigated how we recognise the consequences of our own actions, and why patients with delusions of control confuse self-produced and externally produced actions and sensations. Studies investigating the failure of (...) this 'self-monitoring' mechanism in patients with delusions of control will be discussed in the context of the hypothesis that overactivity in the parietal cortex and the cerebellum contribute to the misattribution of an action to an external source (). (shrink)

In the past dozen years a number of theoretical models of schizophrenic symptoms have been proposed, often inspired by advances in the cognitive sciences, and especially cognitive neuroscience. Perhaps the most widely cited and influential of these is the neurocognitive model proposed by Christopher Frith (1992). Frith's influence reaches into psychiatry, neuroscience, and even philosophy. The philosopher John Campbell (1999a), for example, has called Frith's model the most parsimonious explanation of how self-ascriptions of thoughts are subject to errors of identification. (...) "On reflection, it also seems that this is not just one possible theory; it is the simplest theory which has any prospect of explaining the sense of agency, and we ought to work from it, introducing complications only as necessary" (1999a, p. 612). Not everyone agrees. In their recent analysis of alien voices and inserted thoughts in schizophrenia, Stephens and Graham (2000) offer a critique of Frith. Their criticism, however, although serious, is neither deep nor extensive. They outline three points. First, Frith fails to provide an adequate account of why a subject who experiences thought insertion would misattribute that thought to some other agent. Second, Frith does not clarify the distinction between thought insertion and thought influence. And third, Frith fails to explain how a subject can claim both that he is thinking the thought and that the thought is someone else's thought (Stephens and Graham.. (shrink)

Current models of delusion converge in proposing that delusional beliefs are based on unusual experiences of various kinds. For example, it is argued that the Capgras delusion (the belief that a known person has been replaced by an impostor) is triggered by an abnormal affective experience in response to seeing a known person; loss of the affective response to a familiar person’s face may lead to the belief that the person has been replaced by an impostor (Ellis & Young, 1990). (...) Similarly, the Cotard delusion (which involves the belief that one is dead or unreal in some way) may stem from a general.. (shrink)

Introduction. There is substantial evidence that patients with delusions exhibit a reasoning bias—known as the “jumping to conclusions” bias—which leads them to accept hypotheses as correct on the basis of less evidence than controls. We address three questions concerning the JTC bias that require clarification. Firstly, what is the best measure of the JTC bias? Second, is the JTC bias correlated specifically with delusions, or only with the symptomatology of schizophrenia? And third, is the bias enhanced by emotionally salient material? (...) Methods. To address these questions, we conducted a series of meta-analyses of studies that used the Beads task to compare the probabilistic reasoning styles of individuals with and without delusions. Results. We found that only one of four measures of the JTC bias—“draws to decision”—reached significance. The JTC bias exhibited by delusional subjects—as measured by draws to decision—did not appear to be solely an epiphenomenal effect of schizophrenic symptomatology, and was not amplified by emotionally salient material. Conclusions. A tendency to gather less evidence in the Beads task is reliably associated with the presence of delusional symptomatology. In contrast, certainty on the task, and responses to contradictory evidence, do not discriminate well between those with and without delusions. The implications for the underlying basis of the JTC bias, and its role in the formation and maintenance of delusions, are discussed. (shrink)

The standard approach to the core phenomenology of thought insertion characterizes it in terms of a normal sense of thought ownership coupled with an abnormal sense of thought agency. Recently, Fernández (2010) has argued that there are crucial problems with this approach and has proposed instead that what goes wrong fundamentally in such a phenomenology is a sense of thought commitment, characterized in terms of thought endorsement. In this paper, we argue that even though Fernández raises new issues that enrich (...) the topic, his proposal cannot rival the version of the standard approach we shall defend. (shrink)

The ‘mineness’ of thoughts has often been accepted as indubitable in philosophy. However, the symptom of thought insertion in schizophrenia seems to be an empirical counterexample to the dictum that every introspected thought is one's own. We present a thorough conceptual analysis of mineness of thought, distinguishing between ownership and authorship . We argue that it is indeed a conceptual truth that introspected thoughts are owned by the introspector. However, there are everyday and pathological cases of thoughts, for which we (...) do not ascribe authorship to ourselves. To explain inserted thoughts, however, we need an additional factor which is constituted by the lack of control over inserted thoughts . We present a review of empirical data on thought control and thought insertion in the light of the conceptual analysis. We conclude with a summary of the most important future direction of research. (shrink)

According to the principle known as “the principle of present-tense ascription immunity”, “It is impossible for anyone to have or entertain thoughts without being aware—immediately and self-evidently—that he is thinking that thought”. In other words, my thoughts are fundamentally experienced as mine, and I typically have this experience of mineness immediately, that is, without any inference based on evidence about who is the thinker of the thought. Thought insertion reveals instead that, under particular pathological conditions, people can be startlingly in (...) error about who is thinking a thought. How can this happen? In the attempt to specify how the capacity for self-ascription of a thought can.. (shrink)