INTRODUCTION: Delusional misidentification syndromes (DMS) are a group of psychopathological experiences occurring in psychosis, involving the misidentification of a person or place. DMS are often accompanied by hostility towards the object of delusional misidentification. This is of a particular concern in perinatal mental illness due to the potential disruption of the mother-infant bond, and risk of neglect, violence, or infanticide towards a misidentified child. This review aimed to collate all published cases of DMS in postpartum (...) psychosis to further understand how these syndromes present in perinatal mental illness. METHODS: In August 2021, an online database search was conducted using PubMed, MEDLINE, PsycINFO, CINAHL, and Embase to identify all publications reporting DMS in the perinatal period. RESULTS: Nine papers were included in the review involving 8 case reports of Capgras syndrome and one case series involving 4 cases of Fregoli syndrome. Three cases identified organic pathology, which may have contributed to the presentation. The most common subject of misidentification was the patient’s husband (n = 7), followed by their baby (n = 6), hospital staff (n = 4), other family members (n = 3), and self (n = 1). Five cases remark on the impact of perinatal illness on the maternal-infant bond, of which four result in the mother being unwilling to care for the infant as the result of their delusional beliefs. CONCLUSION: This is the first systematic review of the literature in this field. Although small in number, these cases reveal several important learning points including that DMS can occur with or without underlying organic disease. Active exploration of the nature of delusions in postpartum psychosis is required to mitigate the risk of harm to the infant and mother-infant bond. It may also uncover that these syndromes are more common in postpartum psychosis than previously realized. (shrink)

In this paper I consider a theory developed within cognitive neuropsychiatry to explain two delusions of misidentification, the Capgras and the Cotard delusions. These delusions are classified together with others in which the subject misidentifies persons, places or objects, including parts of her own body. Strictly speaking, the Cotard may not, at the level of content, be a delusion of misidentification, but I have described it as such because the theory I discuss treats it as sharing a causal (...) and a conceptual structure with the Capgras delusion. That theory, associated particularly with the work of Andy Young, raises a Wittgensteinian echo in its claim that, at the subpersonal, information-processing, level, perceptual recognition of familiar faces and scenes is laden with affect. Where affect is absent or distorted as a result of neurological damage the subject “feels” strange in the presence of familiar scenes or people. Thus Young and Leafhead in their discussion of the Cotard delusion: “What the patients often give as evidence of their nonexistence or death is that they don’t have proper feeling.”. (shrink)

In this paper I consider a theory developed within cognitive neuropsychiatry to explain two delusions of misidentification, the Capgras and the Cotard delusions. These delusions are classified together with others in which the subject misidentifies persons, places or objects, including parts of her own body. Strictly speaking, the Cotard may not, at the level of content, be a delusion of misidentification, but I have described it as such because the theory I discuss treats it as sharing a causal (...) and a conceptual structure with the Capgras delusion. That theory, associated particularly with the work of Andy Young, raises a Wittgensteinian echo in its claim that, at the subpersonal, information-processing, level, perceptual recognition of familiar faces and scenes is laden with affect. Where affect is absent or distorted as a result of neurological damage the subject “feels” strange in the presence of familiar scenes or people. Thus Young and Leafhead in their discussion of the Cotard delusion: “What the patients often give as evidence of their nonexistence or death is that they don’t have proper feeling.”. (shrink)

I suggest that we can think of delusional misidentification in terms of systematic errors in the management of mental files. I begin by sketching the orthodox “bottom-up” aetiology of delusional misidentification. I suggest that the orthodox aetiology can be given a descriptivist or a singularist interpretation. I present three cases that a descriptivist interpretation needs to account for. I then introduce a singularist approach, one that is based on mental files, and show how it opens the (...) way for different and potentially more plausible accounts of these three cases. I reflect on how this mental files approach can be viewed either as a supplement to the orthodox aetiology, or as suggesting an altogether different aetiology. I end by addressing a concern surrounding the explanatory power of mental files. (shrink)

This paper contrasts an interactionist account of delusional misidentification with more traditional one- and two-stage models. Unlike the unidirectional nature of these more traditional models, in which the aetiology of the disorder is said to progress from a neurological disruption via an anomalous experience to a delusional belief, the interactionist account posits the interaction of top-down and bottom-up processes to better explain the maintenance of the delusional belief. In addition, it places a greater emphasis on the (...) patient’s underlying phenomenal experience in accounting for the specificity of the delusional content. The role played by patient phenomenology is examined in light of Ratcliffe’s recent phenomenological account. Similarities and differences are discussed. The paper concludes that a purely phenomenological account is unable to differentiate between non-delusional patient groups, who have what appear to be equivalent phenomenal experiences to patients suffering from delusional misidentification but without the delusional belief, and delusional groups, something the interactionist model is able to do. (shrink)

This essay presents a new account of thought insertion. Prevailing views in both philosophy and cognitive science tend to characterize the experience of thought insertion as missing or lacking some element, such as a ‘sense of agency’, found in ordinary first-person awareness of one's own thoughts. By contrast, I propose that, rather than lacking something, experiences of thought insertion have an additional feature not present in ordinary conscious experiences of one's own thoughts. More specifically, I claim that the structure of (...) an experience of thought insertion consists of two distinct elements: a state of ordinary first-person awareness and a sense that this state of awareness is highly unusual. In addition to modeling the experience of thought insertion, I also explain how a delusional pattern of thinking could lead someone who has this kind of experience to adopt a belief that some other entity is inserting thoughts into her mind. Finally, I briefly sketch a neurocomputational framework that could be developed to explain the sense that one's state of first-person awareness is highly irregular. (shrink)

Mirrored-self misidentification is the delusional belief that one's own reflection in the mirror is a stranger. In two experiments, we tested the ability of hypnotic suggestion to model this condition. In Experiment 1, we compared two suggestions based on either the delusion's surface features (seeing a stranger in the mirror) or underlying processes (impaired face processing). Fifty-two high hypnotisable participants received one of these suggestions either with hypnosis or without in a wake control. In Experiment 2, we examined (...) the extent to which social cues and role-playing could account for participants' behaviour by comparing the responses of 14 hypnotised participants to the suggestion for impaired face processing (reals) with those of 14 nonhypnotised participants instructed to fake their responses (simulators). Overall, results from both experiments confirm that we can use hypnotic suggestion to produce a compelling analogue of mirrored-self misidentification that cannot simply be attributed to social cues or role-playing. (shrink)

A recent debate in the literature on delusions centers on the question of whether delusions are beliefs or not. In this paper, an overlooked distinction between egocentric and encyclopedic doxastic states is introduced and brought to bear on this debate, in particular with regard to delusions of misidentification. The result is that a more accurate characterization of the delusional subject’s doxastic point of view is made available. The patient has a genuine egocentric belief (“This man is not my (...) father”), but fails to have the commonly attributed encyclopedic belief (“My father has been replaced by an impostor”). (shrink)

Discussion on the Cotard delusion often focuses on the patient’s delusional belief that he/she is dead. Of interest to this paper, however, is the little referred to claim made by some Cotard patients that they are immortal. How might one explain the juxta-position of death and immortality evident in patients sharing the same clinical diagnosis, and how might these delusional beliefs inform our understanding of patient phenomenology, particularly regarding experiences of existential change? This paper sets out to explain (...) delusions of death and immortality in Cotard patients with reference to changes in their experience of being, owed in part to a conflict in recognition evident in other delusional disorders such as the Capgras and Frégoli delusions. This experiential change is positioned within an interactionist framework of bottom-up and top-down processing that is also compatible with explanationist and endorsement approaches to delusions. (shrink)

Delusional misidentification is commonly understood as the product of an inference on the basis of evidence present in the subject's experience. For example, in the Capgras delusion, the patient sees someone who looks like a loved one, but who feels unfamiliar, so they infer that they must not be the loved one. I question this by presenting a distinction between “recognition” and “identification.” Identification does not always require recognition for its epistemic justification, nor does it need recognition for (...) its psychological functioning. Judgments of identification are often the product of a non-inferential mechanism. Delusional misidentification arises as the product of this mechanism malfunctioning. (shrink)

Discussion on the Cotard delusion often focuses on the patient’s delusional belief that he/she is dead. Of interest to this paper, however, is the little referred to claim made by some Cotard patients that they are immortal. How might one explain the juxta-position of death and immortality evident in patients sharing the same clinical diagnosis, and how might these delusional beliefs inform our understanding of patient phenomenology, particularly regarding experiences of existential change? This paper sets out to explain (...) delusions of death and immortality in Cotard patients with reference to changes in their experience of being, owed in part to a conflict in recognition evident in other delusional disorders such as the Capgras and Frégoli delusions. This experiential change is positioned within an interactionist framework of bottom-up and top-down processing that is also compatible with explanationist and endorsement approaches to delusions. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Philosophy, Psychiatry, & Psychology 11.1 (2004) 35-41 [Access article in PDF] The Rationality of Psychosis and Understanding the Deluded Matthew R. Broome Campbell's important and influential paper (Campbell 2001) has framed the debate that Bayne and Pacherie (2004) most explicitly, and Klee (2004) and Georgaca (2004) more implicitly, engage in. Campbell has offered two broad ways of thinking about explanations of delusions—the empirical and the rational. He offers some (...) criticism of the former and an endorsement of the latter. Campbell uses examples from clinical psychopathology to illustrate his argument and Bayne and Pacherie in turn employ these. Campbell discusses the eponymously named delusions of Capgras and Cotard—the former a subtype of delusional misidentification and the latter a delusion whose content is colored predominantly with nihilistic and possibly hypochondriacal themes. Campbell, Bayne and Pacherie, and Klee discuss the empirical data in relation to such delusions and as an aid to discussing the empirical model more generally. It does seem a little unfortunate that these delusions, which are less than typical, become the focus of Campbell's paper, and Bayne and Pacherie's criticism of his work. Delusions are remarkably heterogeneous; this indeed may be part of the reason why there is so much difficulty in reaching a definition as Klee discusses, and occur in a wide variety of mental and neurological illnesses. The most common delusions are those of persecution and reference (World Health Organization [WHO] 1973) and typically occur in schizophrenia. By contrast, delusional misidentification occurs most commonly in patients with dementia, delirium, and focal cognitive impairment, but can occur in other functional psychoses such as an affective or schizophrenic psychosis. The most common form of delusional misidentification is not that of either the exotic Capgras or Fregoli syndromes but delusional misidentification for place; thus, although Bayne and Pacherie's arguments against Campbell may still hold, delusional misidentification tends to occur in the context of a patient believing that they are at home or on holiday rather than in hospital and may not necessarily involve close family members or other intimate relationships. Similarly, Cotard's syndrome tends to occur in the context of a severe depressive illness with mood-congruent psychotic symptoms, typically in an elderly individual. It does not have to have the content that the deluded is dead, but can include beliefs, for example, that the world no longer exists or that their internal organs are not present. Thus, a patient with either Capgras' or Cotard's syndrome is likely to differ from patients with delusions of persecution. They would [End Page 35] have different diagnoses, probably be older, and have a greater likelihood of structural abnormalities of the brain on imaging and consequent neuropsychological dysfunction. That is not to say that patients with schizophrenia have normal cerebral anatomy and neuropsychology, but rather that the Capgras' and Cotard's patients are likely to have neurological quality to their presentation that is clinically relevant, rather than what commonly the case in schizophrenia and the other functional psychoses, where the neurological abnormalities are only currently important at the level of academic research. Empirical Models of Delusion Formation Different delusions may not have that much in common, nor may the patients who believe in them. This in turn relates to the empirical paradigm that both Campbell and Bayne and Pacherie discuss. It is true that current research, and indeed the clinical practice of cognitive behavioral therapy for psychosis, is indebted to the work of Maher and it is within his legacy which we work. This, however, is not to say that we think his initial formulation was correct. Maher's (1988, 1992) work focused attempts in explaining delusions—both to support and refute his thesis that delusions are the consequence of normal cognitive mechanisms seeking to explain an anomalous sensory experience. Such a view initially led to work demonstrating delusions in the absence of anomalous perceptions, the presence of reasoning biases in the deluded population, and the possibility that abnormal sensory experience may be consequent upon biased cognitive processes (Garety and Freeman 1999). More recent work has demonstrated the prevalence of... (shrink)

Localizing the self in the brain has been the goal of consciousness research for centuries. Recently, there has been an increase in attention to the localization of the self. Here we present data from patients suffering from a loss of self in an attempt to understand the neural correlates of consciousness. Focusing on delusional misidentification syndrome , we find that frontal regions, as well as the right hemisphere appear to play a significant role in DMS and DMS related (...) disorders. These data are placed in the context of neuroimaging findings. (shrink)

Somatoparaphrenia is a pathology of self characterized by the sense of alienaton from parts of one’s body. It is usually construed as a kind of delusional disorder caused by extensive right hemisphere lesions. Lesions in the temporoparietal junction are common in somatoparaphrenia but deep cortical regions (for example, the posterior insula) and subcortical regions (for example, the basal ganglia) are also sometimes implicated (Valler and Ronschi 2009). Patients are often described as feeling that a limb belongs to another person (...) and thus attribute ownership of the limb and bodily sensation to someone else. There is also some question as to whether or not the higher-order thought (HOT) theory of consciousness can plausibly account for the depersonalization psychopathology of somatoparaphrenia (Liang and Lane 2009, Rosenthal 2010, Lane and Liang 2010). Liang and Lane argue that it cannot. The HOT theory of consciousness says that what makes a mental state a conscious mental state is that it is the target of a HOT to the effect that “I am in mental state M” (Rosenthal 2005, Gennaro 2012). When the HOT is itself is unconscious, the conscious state is still outer-directed. When the HOT is conscious, we have introspection and so the conscious thought is directed at the mental state. In section I, I briefly review the previous exchange between Lane and Liang and David Rosenthal. In section II, I further explore somatoparaphrenia and the nature of delusion while offering a number of additional replies to Lane and Liang. In section III, I examine the central notions of “mental state ownership” and “self-concepts” in an effort to account especially for the depersonalization aspect of somatoparaphrenia against the background of HOT theory. In section IV, I argue that to the extent that somatoparaphrenia casts doubt on the notion that some thoughts are “immune to error through misidentification” (IEM), the most fundamental aspect of IEM is still consistent with HOT theory. Overall, I argue that HOT theory is left unscathed by the pheneomenon of somatoparaphrenia and can even help to explain what happens in these cases. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Philosophy, Psychiatry, & Psychology 9.1 (2002) 65-72 [Access article in PDF] Multiple Paths to Delusion Philip Gerrans Response to Phillips JAMES PHILLIPS COMMENTS are summarized in four recommendations. Clarify the Relationship of the Cognitive Model to its Neuroscientific Base The cognitive approach postulates a cognitive entity whose information-processing properties explain a symptom or unify a set of symptoms. The key idea is that we can use a model of (...) normal cognitive functioning to explain a disorder in terms of failure of a component of the model. In the case under discussion, the symptom is the loss of affect, which is part of the clinical profile of both the Capgras and Cotard delusions. The body of neuropsychological data concerning links between recognitional and affective processes extends back at least to Charcot's patient M. X. whose affective responses to familiar situations were lost, together with his visual episodic memory. M. X described his phenomenology this way: A remarkable consequence of this loss of mental ability is, as I have said, the change in my personality and impressions. I am much less affected by sorrow or grief. I can tell you that, after losing one of my relatives with whom I was very close, I experienced a much less intense grief than if I had still been able to image the features of that relative, the stages of the illness he went through, or especially if I had been able to picture to myself [voir interieurement] the outward effect of this untimely death on the members of my family. (Young and van de Wal 1996) (It is interesting to note that M. X. retained insight into his condition and explained it in a lucid, rational way rather than forming a delusional belief. Initial evidence for a two-stage theory, one might have thought).Given convergent evidence that the limbic system is the basis of affective states, the hypothesis that the delusions under discussion are rationalizations of unusual affective experiences consequent on abnormal limbic function or loss of connection between limbic and other functions is an inference to the best explanation. The Young-Ellis model is a cognitive model that describes cognitive function at what Dennett calls the design level, intermediate between what Marr called the computational level and level of representation and algorithm. As such it implies only that the boxes and arrows are implemented neurally, but endorses no hypotheses about the nature of that implementation.It is correct of Phillips to observe that the crucial inference about the link between affective and cognitive function is grounded in a background theory of the relationship between cognitive models, clinical symptoms, and neurobiology. If Phillips' complaint is that the model cannot be sheeted home to a neurobiological substrate, [End Page 65] this is true. Implementation theories are thin on the ground in cognitive science because they would require a theory of biological computation that, despite partisan claims, is elusive. Nonetheless, information-processing models and partial implementation theories for specific functions such as perception, language, face recognition, and the affective systems do exist. The allusion to cognitive structure remains sound as long as it accounts for observable clinical and experimental data and makes verifiable predictions.The fact that the Young-Ellis model of face recognition can account for both normal function and a variety of forms of prosopagnosia together (under assumptions about the relation between belief and experience) with delusions of misidentification counts in its favor (Ellis 1998).Phillips objection to cognitive theories is stronger when we turn to models of belief and rationality. In the case of functions such as face recognition or language, there is a variety of convergent evidence, especially from deficit studies, to support a model of normal cognitive function. For example, we know that face recognition activates schemas concerning orientation, features, emotions, and gender because these components can be selectively damaged (Young 1998). However, we lack a model of normal human reasoning other than "folk theory" of belief-desire psychology. Cognitive theories of belief formation are often forced to use models derived from philosophy such as logic, probability theory, or decision theory, which are amenable to... (shrink)

Does the formation of delusions involve abnormal reasoning? According to the prominent ‘two-factor’ theory of delusions (e.g. Coltheart, 2007), the answer is yes. The second factor in this theory is supposed to affect a deluded individual's ability to evaluate candidates for belief. However, most published accounts of the two-factor theory have not said much about the nature of this second factor. In an effort to remedy this shortcoming, Coltheart, Menzies and Sutton (2010) recently put forward a Bayesian account of inference (...) in delusions. I outline some criticisms of this important account, and sketch an alternative account of delusional inference that, I argue, avoids these criticisms. Specifically, I argue that the second factor in delusion formation involves a systematic deviation from Bayesian updating, a deviation that may be characterized as a bias towards ‘explanatory adequacy’. I present a numerical model of this idea and show that my alternative account is broadly consistent with prominent prediction error models of delusion formation (e.g. Corlett, Murray et al., 2007). (shrink)

It is widely held that introspection-based self-ascriptions of mental states are immune to error through misidentification , relative to the first person pronoun. Many have taken such errors to be logically impossible, arguing that the immunity holds as an “absolute” necessity. Here I discuss an actual case of craniopagus twins—twins conjoined at the head and brain—as a means to arguing that such errors are logically possible and, for all we know, nomologically possible. An important feature of the example is (...) that it is one where a person may be said to be introspectively aware of a mental state that occurs outside of her own mind. Implications are discussed for views of the relation between introspection and mental state ownership, and between introspection and epistemic criteria for the “mark of the mental.”. (shrink)

The patient with Capgras’ syndrome claims that people very familiar to him have been replaced by impostors. I argue that this disorder is due to the destruction of a representation that the patient has of the mind of the familiar person. This creates the appearance of a familiar body and face, but without the familiar personality, beliefs, and thoughts. The posterior site of damage in Capgras’ is often reported to be the temporoparietal junction, an area that has a role in (...) the mindreading system, a connected system of cortical areas that allow us to attribute mental states to others. Just as the Capgras’ patient claims that that man is not his father, the patient with asomatognosia claims that his arm is not really his. A similar account applies here, in that a nearby brain area, the supramarginal gyrus, is damaged. This area works in concert with the temporoparietal junction and other areas to produce a large representation of a mind inside a body situated in an environment. Damage to the mind-representing part of this system (coupled with damage to executive processes in the prefrontal lobes) causes Capgras’ syndrome, whereas damage to the body-representing part of this system (also coupled with executive damage) causes asomatognosia. (shrink)

In both cognitive science and philosophy, many theorists have recently appealed to a predictive processing framework to offer explanations of why certain individuals form delusional beliefs. One aim of this essay will be to illustrate how one could plausibly develop a predictive processing account in different ways to account for the onset of different kinds of delusions. However, the second aim of this essay will be to discuss two significant limitations of the predictive processing framework. First, I shall draw (...) on the structure of explanatory why-questions to argue that predictive processing theories can only partially explain the formation of delusional beliefs. Second, I shall argue that predictive processing theories cannot explain how implausible delusional hypotheses are generated. Yet understanding why an agent even generates a delusional hypothesis is a crucial step to understanding why she eventually comes to believe it. The final section of the essay presents three alternative ways the process of hypothesis generation might be functionally divergent in cases of delusional cognition. (shrink)

Delusions are deeply evidence-resistant. Patients with delusions are unmoved by evidence that is in direct conflict with the delusion, often responding to such evidence by offering obvious, and strange, confabulations. As a consequence, the standard view is that delusions are not evidence-responsive. This claim has been used as a key argumentative wedge in debates on the nature of delusions. Some have taken delusions to be beliefs and argued that this implies that belief is not constitutively evidence-responsive. Others hold fixed the (...) evidenceresponsiveness of belief and take this to show that delusions cannot be beliefs. Against this common assumption, I appeal to a large range of empirical evidence to argue that delusions are evidence-responsive in the sense that subjects have the capacity to respond to evidence on their delusion in rationally permissible ways. The extreme evidence-resistance of delusions is a consequence of powerful masking factors on these capacities, such as strange perceptual experiences, motivational factors, and cognitive biases. This view makes room for holding both that belief is constitutively evidence-responsive and that delusions are beliefs, and it has important implications for the study and treatment of delusions. (shrink)

In Paradoxes of Delusion, Sass aims to use passages from Wittgenstein to characterize the feeling of “mute particularity” that forms a part of delusional atmosphere. I argue that Wittgenstein’s discussion provides no helpful positive account. But his remarks on more everyday cases of the uncanny and the feeling of unreality might seem to promise a better approach via the expressive use of words in secondary sense. I argue that this also is a false hope but that, interestingly, there can (...) be no interesting or substantial explanation of this failure. (shrink)

In order to explain delusional beliefs, one must first consider what factors should be included in a theory of delusion. Unlike a one-factor theory, a two-factor theory of delusion argues that not only anomalous experience (the first factor) but also an impairment of the belief-evaluation system (the second factor) is required. Recently, two-factor theorists have adopted various Bayesian approaches in order to give a more accurate description of delusion formation. By reviewing the progression from a one-factor theory to a (...) two-factor theory, I argue that in light of the second factor’s requirements, different proposed impairments can be unified within a consistent belief-evaluation system. Under this interpretation of the second factor, I further argue that the role of a mechanism responsible for detecting bizarreness is wrongly neglected. I conclude that the second factor is a compound system which consists of differing functional parts, one of which functions to detect bizarreness in different stages of delusion; moreover, I hold that the impairment can be one or several of these functional parts. (shrink)

The aim of this article is to analyze those theories that interpret misidentification delusions in terms of mentalization. The hypothesis under examination holds that a mentalization framework is useful for describing misidentification delusions when identification is thought to be partially based on mentalization. The article provides both a characterization and possible interpretations of such delusions, and possible relations between misidentification and mentalization are scrutinized. Whether the mentalization approach may explain or describe such kinds of mental disorders is (...) considered, with the conclusion that while this approach is unsatisfactory, there is some room for future improvement. (shrink)

Sidney Shoemaker credits Wittgenstein’s Blue Book with identifying a special kind of immunity to error that is characteristic of ‘I’ in its “use as subject”. This immunity to error is thought by Shoemaker, and by many following him, to be central to the meaning of ‘I’ and thus to the topics of self-knowledge, self-consciousness and personal memory. This paper argues that Wittgenstein’s work does not contain the thesis, nor any version of the thesis, that there is a use of ‘I’—‘use (...) as subject’—which is ‘immune to error through misidentification’. It offers an interpretative corrective and shows that the passage in question is part of a deep challenge to IEM and to accounts of first-person thought that begin with the idea that there are two uses of the word ‘I’. With the corrective in place novel perspectives on the relation between self-consciousness and subjectivity become visible. (shrink)

Philosophers have been long interested in delusional beliefs and in whether, by reporting and endorsing such beliefs, deluded subjects violate norms of rationality (Campbell 1999; Davies & Coltheart 2002; Gerrans 2001; Stone & Young 1997; Broome 2004; Bortolotti 2005). So far they have focused on identifying the relation between intentionality and rationality in order to gain a better understanding of both ordinary and delusional beliefs. In this paper Matthew Broome and I aim at drawing attention to the extent (...) to which deluded subjects are committed to the content of their delusional beliefs, that is, to whether they can be regarded as authors of their beliefs (Moran 2001). We consider several levels of commitment one can have to a reported belief, delusional or otherwise, and we distinguish between _ownership_ and _authorship_ of beliefs (Gallagher 2000). After examining some examples of belief authoring (or lack thereof) in psychopathology, we argue that there is no straight-forward and unitary answer to the question whether deluded subjects author their beliefs. Nevertheless, introducing the notion of authorship in the debate can significantly contribute to the philosophical literature on the rationality of delusions and can also have important implications for diagnosis and therapy in psychiatry. (shrink)

Delusional mood is a well-recognized psychological state, often present in the prodromal stage of schizophrenia. Various phenomenological psychopathologists have proposed that delusional mood may not only precede but also contribute to the later formation of schizophrenic delusion. Hence, understanding experiential abnormalities involved with the delusional mood have been considered central for the understanding of schizophrenic delusion. Ranging from traditional and contemporary phenomenological and neurobiological accounts, it has been often mentioned that the peculiar affective saliency of the world (...) experience may underpin the emergence of delusional mood. In this paper, I employ Edmund Husserl’s account of affection and affective syntheses to clarify the nature of such an experience and illuminate how this experiential abnormality contributes to the emergence of the delusional mood. I conclude by relating the phenomenological account I advance here with a neurobiological account of aberrant salience hypothesis and chart out a possible way toward mutual enlightenment for both approaches. (shrink)

The suggested model is discussed with reference to two clinical populations with memory disorders – patients with misidentification syndromes and those with source memory impairment, both of whom may present with (broadly conceived) déjà vu phenomenon, without insight into false feeling of familiarity. The role of the anterior thalamic nucleus and retrosplenial cortex for autobiographical memory and familiarity is highlighted.

Delusional beliefs have sometimes been considered as rational inferences from abnormal experiences. We explore this idea in more detail, making the following points. Firstly, the abnormalities of cognition which initially prompt the entertaining of a delusional belief are not always conscious and since we prefer to restrict the term “experience” to consciousness we refer to “abnormal data” rather than “abnormal experience”. Secondly, we argue that in relation to many delusions (we consider eight) one can clearly identify what the (...) abnormal cognitive data are which prompted the delusion and what the neuropsychological impairment is which is responsible for the occurrence of these data; but one can equally clearly point to cases where this impairments is present but delusion is not. So the impairment is not sufficient for delusion to occur. A second cognitive impairment, one which impairs the ability to evaluate beliefs, must also be present. Thirdly (and this is the main thrust of our chapter) we consider in detail what the nature of the inference is that leads from the abnormal data to the belief. This is not deductive inference and it is not inference by enumerative induction; it is abductive inference. We offer a Bayesian account of abductive inference and apply it to the explanation of delusional belief. (shrink)

In this collection of newly commissioned essays, the contributors present a variety of approaches to it, engaging with historical and empirical aspects of the subject as well as contemporary philosophical work.

Misidentification syndromes occur commonly in neuropsychiatric practice and can be explained through aberrant integration of recollection and familiarity, in keeping with a dysfunction at the level of the attributional system in the new integrative memory model. We examine neuroimaging findings associated with Fregoli and Capgras syndromes and compare these with the proposed neural substrate of the integrative memory model supporting the core and attribution functions.

Identifying demonstratives are of the form 'this d', Where d is a descriptive noun phrase. I am concerned with the effect of a misidentifying identifying demonstrative on the truth of propositions such as 'this d is p'; I argue there are circumstances in which 'this d is p' can be true when the referent of 'this d' is a p but is not a d. Extending the results, I argue there are circumstances where 'i know that this d is p' (...) and 'i believe that this d is p' can be true when the referent of 'this d' is a p but is not a d. The philosophical importance of the results is discussed. (shrink)

The relationship between dream content and waking life experiences remains difficult to decipher. However, some neurobiological findings suggest that dreaming can, at least in part, be considered epiphenomenal to ongoing memory consolidation processes in sleep. Both abnormalities in sleep architecture and impairment in memory consolidation mechanisms are thought to be involved in the development of psychosis. The objective of this study was to assess the continuity between delusional contents and dreams in acutely psychotic patients. Ten patients with a single (...) fixed and recurring delusional content were asked to report their dreams during an acute psychotic break. Sixteen judges with four different levels of acquaintance to the specific content of the patients’ delusions were asked to group the dreams, expecting that fragments of the delusional thought would guide the task. A mathematical index was developed in order to compare correct groupings between the four groups of judges. Most judges grouped the dreams slightly above chance level and no relevant differences could be found between the four groups [F = 1.297; p = n.s.]. Scoring of dreams for specific delusional themes suggested a continuity in terms of dream and waking mentation for two contents . These findings seem to suggest that at least some delusional contents recur within patients’ dreams. Future studies will need to determine whether such continuity reflects ongoing consolidation processes that are relevant to current theories of delusion formation and stabilization. (shrink)

Even more than for other treatments, great importance must be given to informed consent in the case of electroconvulsive therapy. In a percentage of cases, the symbolic connotation of the treatment, even if mostly and intrinsically negative, may actually be a determining factor in the patient’s motives for giving consent. On an ethical and medicolegal level, the most critical point is that concerning consent to the treatment by a psychotic subject with a severely compromised ability to comprehend the nature and (...) objective of the proposed therapy, but who nonetheless expresses his consent, for reasons derived from delusional thoughts. In fact, this situation necessarily brings to light the contradiction between an explicit expression of consent, a necessary formality for the commencement of therapy, and the validity of this consent, which may be severely compromised due to the patient’s inability to comprehend reality and therefore to accept the proposal of treatment, which is intrinsic to this reality. With the use of an electric current, the symbolic experience associated with anaesthesia, and the connection to convulsions, ECT enters the collective consciousness. In relation to this, ECT is symbolic of these three factors and hooks on to the thoughts, fears, feelings and expectations of delusional patients. These are often exemplified in the violent intervention of the persecutor in the patient with schizophrenia, the expected punishment for the ’error’ committed for which the depressed patient blames himself and the social repression of the maniacal patient’s affirmation of his inflated self-esteem. (shrink)

How is confabulation related to self-deception? Obviously, that depends on what confabulation and self-deception are. In the first main section, I sketch a position that I have developed elsewhere on self-deception. I turn to confabulation in the second main section. Confabulation in general is more than I can take on in this chapter. I focus on confabulations associated with a trio of delusions.

I argue that immunity to error through misidentification primarily characterizes thoughts that are 'implicitly' de se, as opposed to thoughts that involve an explicit self-identification. Thoughts that are implicitly de se involve no reference to the self at the level of content: what makes them de se is simply the fact that the content of the thought is evaluated with respect to the thinking subject. Or, to put it in familiar terms : the content of the thought is a (...) property which the thinking subject self-ascribes (as in the Loar/Lewis/Chisholm analysis). After answering an objection (to the effect that immunity can affect explicit de se thoughts), I extend the analysis to demonstrative thoughts, which also exhibit the property of immunity to error through misidentification. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Philosophy, Psychiatry, & Psychology 11.1 (2004) 95-99 [Access article in PDF] Delusional Content and the Public Nature of Meaning:Reply to the Other Contributors Robert Klee The contribution by professors Bayne and Pacherie (2004) is an earnest attempt to defend a popular model of monothematic delusions against criticisms launched by John Campbell (2001). This model of monothematic delusions holds that such delusions are rational attempts by the sufferer to (...) explain to herself specific kinds of anomalous sensory/affective experiences. Bayne, Pacherie, Campbell, and for that matter Sass, Harper, and Georgaca, write as if semantic meaning accrued to words in a language term by term, as if meaning is "private" to the deluded person, and that she might therefore mean almost anything by her own idiosyncratic use of the public language she otherwise speaks. This is a notorious mistake. As Hilary Putnam famously put it in his classic 1975 paper "The meaning of 'meaning,'" "Cut the pie any way you like, 'meanings' just ain't in the head" (1975, 227). That is, meanings are not ethereal interior mental objects, private to the speaker—they are not private inner episodes that take place in some mental center stage of consciousness. The deluded person does not and cannot succeed in changing the meaning of a term in a public language like English merely by an individual act of imaginative will involving the making of a bizarre assertion—not even if she repeats it a thousand times. The public nature of meaning, if I can coin a phrase for it, is the central theme in the work of the later Wittgenstein. Even before Putnam, Wittgenstein had made the same point in his Philosophical Investigations via a famous footnote in which he writes, Can I say 'bububu' and mean "If it doesn't rain I shall go for a walk"?—it is only in a language that I can mean something by something. This shows clearly that the grammar of 'to mean' is not like that of the expression 'to imagine' and the like." (2001, 18e) Wittgenstein argues that the answer to the rhetorical question in the footnote is an emphatic No. To mean something by the use of words in a public language is not equivalent to an act of individual free imagination. The languages we each speak, including the unfortunately deluded among us, are public not private, and insofar as the notion of meaning has an understandable sense, the meaning of a term is fixed by its actual public use, across large time intervals, in many different contexts, by the many millions of speakers of the language in question. It is time that segments of the intellectual map beyond the borders [End Page 95] of philosophy got the news about this, for I think an appreciation of this point would forestall certain objections and argumentative moves that otherwise take up space in the psychological literature.Bayne and Pacherie (2004) describe Campbell's model of monothematic delusions as proposing that "delusions can be usefully regarded as Wittgensteinian framework propositions" (p. 7). I have discussed this notion in my main paper, although I do not use the terms framework propositions; I stick to Wittgenstein's own words. Wittgenstein called them, literally in the German, propositions that "stand fast for us" (feststehen). This description strikes me as less misleading than calling them framework propositions, for the latter expression suggests that they could in some sense be replaceable by a different framework of framework propositions, something that Wittgenstein in no way ever meant to suggest. Wittgenstein did not think of these propositions as individualized or privately owned—as beliefs that might vary considerably across the population of speakers of the language in which they are expressed. That is why he explicitly wrote that they stand fast for us. Note the plural pronoun. There is something irreducibly collective, something publicly owned, about the epistemology of these propositions. These propositions represent the accumulated certainties that precipitate out of what is commonly shared in human experience over long time intervals. Precisely because what stands fast for us is... (shrink)

Jennifer Radden has drawn attention to two features of delusion, ambivalence and subjectivity, which are problematic for theories of delusion that treat delusions as empirical beliefs. She argues for an ‘attitude’ theory of delusion. I argue that once the cognitive architecture of delusion formation is properly described the debate between doxastic and attitude theorists loses its edge. That architecture suggests that delusions are produced by activity in the ‘default mode network’ unsupervised by networks required for decontextualized processing. The cognitive properties (...) of these networks explain the features of delusion which generate the debate between doxastic and attitude theorists. (shrink)

This paper responds to arguments due to Joel Smith and Annalisa Coliva that try to show that James Pryor’s notion of wh-misidentification is philosophically uninteresting, and perhaps even spurious. It also proposes definitions of wh-misidentification and immunity to wh-misidentification which try to improve in various ways on the characterisations that standardly figure in the literature, and explores the relationship between misidentification and the epistemic structures characteristic of some kinds of Gettier cases.

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)