Other Disorders and Syndromes

This chapter provides a brief overview of the history of behavioral neurology, dividing it roughly into six eras. In the ancient and classical eras, emphasis is placed on two transitions: firstly, from descriptions of head trauma and attempted neurosurgical treatments to the exploratory dissections during the Hellenistic period and the replacement of cardiocentrism; and secondly, to the more systematic investigations of Galenus and the rise of pneumatic ventricular theory. In the medieval through post-Renaissance eras, the scholastic consolidation of knowledge and (...) the role of compendia are emphasized, along with the use of new methods from within a mechanistic framework. With the discovery of electrical conductance and the rise of experimentalism, we frame the modern era as period of intense debate over localization, decomposition, and other mechanistic principles, and marked by rapid discovery about the brain. The chapter ends with a discussion of the contemporary era, focusing on the establishment of behavioral neurology research on aphasia, apraxia, and neuropsychiatric conditions. (shrink)

Difficulties in distinguishing veridical reports of experience from confabulations have implications for theories of consciousness. I develop some of these implications through a consideration of out-of-body experiences (OBEs). Do these variations indicate individual variation in experience or are they post-hoc confabulations, stories told by subjects to themselves in an attempt to make sense of the core phenomenology? I argue that no existent or possible evidence would be sufficient to favour one hypothesis over the other. How such evidence is interpreted depends (...) on prior commitments to one or other of these hypotheses or to a theory of consciousness that is not neutral as to these hypotheses. One of these types of theory, namely vehicle theories, has difficulty accommodating the existence of confabulations and so allows for only the elaborate phenomenology hypothesis. Because we cannot know that reports are not confabulations, vehicle theories are insufficient to explain OBEs. (shrink)

Time is an essential feature in bipolar disorder (BP). Manic and depressed BP patients perceive the speed of time as either too fast or too slow. The present article combines theoretical and empirical approaches to integrate phenomenological, psychological, and neuroscientific accounts of abnormal time perception in BP. Phenomenology distinguishes between perception of inner time, ie, self-time, and outer time, ie, world-time, that desynchronize or dissociate from each other in BP: inner time speed is abnormally slow (as in depression) or fast (...) (as in mania) and, by taking on the role as default-mode function, impacts and modulates the perception of outer time speed in an opposite way, ie, as too fast in depression and too slow in mania. Complementing, psychological investigation show opposite results in time perception, ie, time estimation and reproduction, in manic and depressed BP. Neuronally, time speed can be indexed by neuronal variability, ie, SD. Our own empirical data show opposite changes in manic and depressed BP (and major depressive disorder [MDD]) with abnormal SD balance, ie, SD ratio, between somatomotor and sensory networks that can be associated with inner and outer time. Taken together, our combined theoretical-empirical approach demonstrates that desynchronization or dissociation between inner and outer time in BP can be traced to opposite neuronal variability patterns in somatomotor and sensory networks. This opens the door for individualized therapeutic “normalization” of neuronal variability pattern in somatomotor and sensory networks by stimulation with TMS and/or tDCS. (shrink)

The distinction between body image and body schema has been incredibly influential in cognitive neuroscience. Recently, researchers have begun to speculate about the relationship between these representations (Gadsby, 2017, 2018; Pitron & de Vignemont, 2017; Pitron et al., 2018). Within this emerging literature, Pitron et al. (2018) proposed that the long-term body image and long-term body schema co-construct one another, through a process of reciprocal interaction. In proposing this model, they make two assumptions: that the long-term body image incorporates the (...) spatial characteristics of tools, and that it is distorted in the case of Alice in wonderland syndrome. Here, I challenge these assumptions, with a closer examination of what the term “long-term body image” refers to. In doing so, I draw out some important taxonomic principles for research into body representation. -/- . (shrink)

The Idea of the World offers a grounded alternative to the frenzy of unrestrained abstractions and unexamined assumptions in philosophy and science today. This book examines what can be learned about the nature of reality based on conceptual parsimony, straightforward logic and empirical evidence from fields as diverse as physics and neuroscience. It compiles an overarching case for idealism - the notion that reality is essentially mental - from ten original articles the author has previously published in leading academic journals. (...) The case begins with an exposition of the logical fallacies and internal contradictions of the reigning physicalist ontology and its popular alternatives, such as bottom-up panpsychism. It then advances a compelling formulation of idealism that elegantly makes sense of - and reconciles - classical and quantum worlds. The main objections to idealism are systematically refuted and empirical evidence is reviewed that corroborates the formulation presented here. The book closes with an analysis of the hidden psychological motivations behind mainstream physicalism and the implications of idealism for the way we relate to the world. (shrink)

Background and Objective: Understanding how trauma impacts the self-structure of individuals suffering from the Post-Traumatic Stress Disorder (PTSD) symptoms is a complex matter and despite several attempts to explain the relationship between trauma and the “Self”, this issue still lacks clarity. Therefore, adopting a new theoretical perspective may help understand PTSD deeper and to shed light on the underlying psychophysiological mechanisms. Methods: In this study, we employed the “three-dimensional construct model of the experiential selfhood” where three major components of selfhood (...) (phenomenal first-person agency, embodiment, and reflection/narration) are related to three Operational Modules (OMs) of the self-referential brain network. These modules can be reliably estimated through operational synchrony analysis of the Electroencephalogram (EEG). Six individuals with PTSD symptoms and twenty-nine sex-, age- and demographic- (race, education, marital status) matched healthy controls underwent resting state EEG signal acquisition with the following estimation of the synchrony strength within every OM. Results: Our results indicate that subjects with PTSD symptoms had significantly stronger EEG operational synchrony within anterior and right posterior OMs as well as significantly weaker EEG operational synchrony within left posterior OM compared to healthy controls. Moreover, increased the functional integrity of the anterior OM was positively associated with hyperactivity symptoms, reduced synchrony of the left posterior OM was associated with greater avoidance, and increased right posterior OM integrity was positively correlated with intrusion and mood symptoms. Conclusion: The results are interpreted in light of the triad model of selfhood and its theoretical and clinical implications (including a new treatment approach) are discussed. (shrink)

The distinction between the body schema and the body image has become the stock in trade of much recent work in cognitive neuroscience and philosophy. Yet little is known about the interactions between these two types of body representations. We need to account not only for their dissociations in rare cases, but also for their convergence most of the time. Indeed in our everyday life the body we perceive does not conflict with the body we act with. Are the body (...) image and the body schema then somehow reshaping each other or are they relatively independent and do they only happen to be congruent? On the basis of the study of bodily hallucinations, we consider which model can best account for the body schema/body image interactions. (shrink)

Descartes was certain that he was thinking and he was accordingly certain that he existed. Like Descartes, we seem to be more certain of our thoughts and our existence than of anything else. What is less clear is the reason why we are thus certain. Philosophers throughout history have provided different interpretations of the cogito, disagreeing both on the kind of thoughts it characterizes and on the reasons for its cogency. According to what we may call the empiricist interpretation of (...) the cogito, I can only claim to be certain of having experiences, and this certainty, as well as that of my own existence, stems from their phenomenal and subjective character. According to rationalist interpretations, on the other hand, I am certain of having some self-reflexive propositional attitudes, and this certainty derives from their rational features. Psychiatric patients suffering from acute forms of depersonalization or of the Cotard syndrome often doubt that they think and exist, and might even believe that they don't. I argue that their study allows us to favor the empiricist interpretation of the cogito. (shrink)

Recent evidence points to widespread underconnectivity in autistic brains owing to deviant white matter, the fibers that make long connections between areas of the cortex. Subjects with autism show measurably fewer long-range connections between the parietal and prefrontal cortices. These findings may help shed light on the current debate in the consciousness literature about whether conscious states require both prefrontal and parietal/temporal components. If it can be shown that people with autism have conscious states despite such underconnectivity, this would constitute (...) an argument for the claim that conscious states can exist in posterior cortex without associated prefrontal activity. This in turn lends support to a class of theories according to which microconsciousness is possible—consciousness in small areas of cortex without active connections to the prefrontal cortex, as opposed to the higher-order thought (HOT) theory of consciousness, according to which conscious states can only occur when posterior cortical areas (in the parietal or temporal lobes) have active connections to the prefrontal cortex. In this chapter, after listing several candidate examples of consciousness without accompanying prefrontal connections, I will argue that autism provides yet another such example. I will also examine a recent version of the higher-order theory that acknowledges these cases of consciousness without prefrontal activity and, instead depicts consciousness as requiring higher-order thoughts located in posterior cortex. In the final section, I will examine the consequences of these views for our understanding of the metaphysical nature of consciousness itself—the classic mind-body problem. (shrink)

Common sense suggests that visual consciousness is essential to skilled motor action, but Andy Clark—inspired by Milner and Goodale's dual visual systems theory—has appealed to a wide range of experimental dissociations to argue that such an assumption is false. Critics of Clark's argument contend that the content driving motor action is actually within subjects' experience, just not easily discovered. In this article, I argue that even if such content exists, it cannot be guiding motor action, since a review of current (...) visual neuroscience indicates that the visual brain areas producing conscious representations are distinct from those driving motor action. (shrink)

In this report, we describe the case of a patient who has remained in a comatose state for more than one year after a traumatic and hypoxic brain injury. This state, which we refer to as long-lasting coma (LLC), may be a disorder of consciousness with significantly different features from those of conventional coma, the vegetative state, or brain death. On the basis of clinical, neurophysiological and neuroimaging data, we hypothesize that a multilevel involvement of the ascending reticular activating system (...) is required in LLC. This description may be useful for the identification of other patients suffering from this severe disorder of consciousness, which raises important ethical issues. (shrink)

Introduction - From the Illiad to the Studies on Hysteria: A chronology of the discovery of the unconscious mind - Freud's theories of the unconscious mind - Jung's collective unconscious - Lacan's linguistic paradigm.

Disturbed identity is one of the defining characteristics of Borderline Personality Disorder manifested in a broad spectrum of dysfunctions related to the self, including disturbances in meaning-generating self-narratives. Autobiographical memories are memories of personal events that provide crucial building-blocks in our construction of a life-story, self-concept, and a meaning-generating narrative identity. The cultural life script represents culturally shared expectations as to the order and timing of life events in a prototypical life course within a given culture. It is used to (...) organize one’s autobiographical memories. Here, 17 BPD-patients, 14 OCD-patients, and 23 non-clinical controls generated three important autobiographical memories and their conceptions of the cultural life script. BPD-patients reported substantially more negative memories, fewer of their memories were of prototypical life script events, their memory narratives were less coherent and more disoriented, and the overall typicality of their life scripts was lower as compared with the other two groups. (shrink)

Mania and hypomania involve dysfunctional beliefs about the self, others, and the world, as well about affect regulation. The present study explored the impact of these beliefs on self-defining memories and self-defining future projections of individuals with a history of hypomanic symptoms. The main findings showed that a history of hypomanic symptoms was related to enhanced retrieval of memories describing positive relationships and to reduced future projections about relationships, suggesting both a need for social bonding and a striving for autonomy. (...) Moreover, hypomania-prone individuals tended to describe more recent events and to produce self-defining memories with references to tension that were more integrated in their self-structure. All of these findings support the presence of conflicting dysfunctional beliefs and the importance of memories containing references to tension in hypomania. (shrink)

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

According to Rosenthal’s Higher-Order Thought (HOT) theory of consciousness, first-order mental states become conscious only when they are targeted by HOTs that necessarily represent the states as belonging to self. On this view a state represented as belonging to someone distinct from self could not be a conscious state. Rosenthal develops this view in terms of what he calls the ‘thin immunity principle’ (TIP). According to TIP, when I experience a conscious state, I cannot be wrong about whether it is (...) I who I think is in that state. We first suggest that TIP is a direct consequence of the HOT theory. Next we argue that somatoparaphrenia—a pathology in which sensations are sometimes represented as belonging to other people—shows that TIP can be violated. This violation of TIP in turn shows that the HOT theory’s claim that conscious states are necessarily represented as belonging to self is in error. Rosenthal’s attempt to account for pathological cases is found to be inadequate when applied to somatoparaphrenia, and other possible defenses are also shown to be incapable of preserving TIP. We further conclude by suggesting that the HOT theory’s failing in this regard is not a failing that is peculiar to this theory of consciousness. (shrink)

David Milner and Melvyn Goodale, and the many psychologists and philosophers who have been influenced by their work, claim that ‘the visual system that gives us our visual experience of the world is not the same system that guides our movements in the world’. The arguments that have been offered for this surprising claim place considerable weight on two sources of evidence — visual form agnosia and the reaching behaviour of normal subjects when picking up objects that induce visual illusions. (...) The present article shows that, if we are careful to consider the possibility that a demonstrative gesture can contribute content to a conscious experience, then neither source of evidence is compelling. (shrink)

Studies of perception have focussed on sensation, though more recently the perception of action has, once more, become the subject of investigation. These studies have looked at acute experimental situations. The present paper discusses the subjective experience of those with either clinical syndromes of loss of movement or sensation (spinal cord injury, sensory neuronopathy syndrome or motor stroke), or with experimental paralysis or sensory loss. The differing phenomenology of these is explored and their effects on intention and agency discussed. It (...) is shown that sensory loss can have effects on the focussing of motor command and that for some a sense of agency can return despite paralysis. (shrink)

Zadra, Desjardins, and Marcotte tested several predictions derived from the Threat Simulation Theory of dreaming in a large sample of recurrent dreams. In response to these findings, Valli and Revonsuo presented a commentary outlining alternate conceptualizations and explanations for the results obtained. We argue that many points raised by Valli and Revonsuo do not accurately reflect our main findings and at times present a biased assessment of the data. In this article, we provide necessary clarifications and responses to each one (...) of their main points of discussion. (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)

Rehabilitation For Traumatic Brain Injury (TBI) is a state-of-the-science review of the effectiveness of rehabilitation interventions.

The interest of this is threefold. First, patients with altered states of consciousness continue to represent a major clinical problem in terms of clinical assessment of consciousness and daily management.

Written by leading experts in the field, this invaluable text situates the practice of cognitive and behavioral rehabilitation in the latest research from ...