Melnyk provides a rigorous analysis of the notion of realization with the aim of defining Physicalism. It is argued here that contrary to Melnyk's Realization Physicalism, the idea that mental phenomena are realized by physical phenomena fails to capture the physicalist belief that the former obtain in virtue of the latter. The conclusion is not that Physicalism is false, but that its truth is best explained with some notion other than realization in Melnyk's sense. I also argue that the problems (...) with Melnyk's brand of Realization Physicalism generalize to other potential attempts to express Physicalism in terms of realization. The burden of proof is on the Realization Physicalist to show that physicalist intuitions can be adequately captured with the notion of realization. (shrink)

Within Piaget there is an implicit theory of the development of explicit memory. It rests in the dynamical trajectory underlying the development of causality, object, space and time – a complex (COST) supporting a symbolic relationship integral to the explicit. Cassirer noted the same dependency in the phenomena of aphasias, insisting that a symbolic function is being undermined in these deficits. This is particularly critical given the reassessment of Piaget’s stages as the natural bifurcations of a self-organizing dynamic system. The (...) elements of a theoretical framework required to support explicit memory are developed, to include, (1) the complex developmental trajectory supporting the emergence of the explicit in Piaget, (2) the concrete dynamical system and the concept of a non-differentiable time contained in Bergson’s theory required to support a conscious, as opposed to an implicit remembrance, (3) the relation to current theories of amnesia, difficulties posed by certain retrograde amnesic phenomena, the role of the hippocampus and limitations of connectionist models, (4) the fact that nowhere in this overall framework does the loss of explicit memory imply or require the destruction of experience “stored in the brain.”. (shrink)

Viewed from a first-person perspective consciousness appears to be necessary for complex, novel human activity - but viewed from a third-person perspective consciousness appears to play no role in the activity of brains, producing a "causal paradox". To resolve this paradox one needs to distinguish consciousness of processing from consciousness accompanying processing or causing processing. Accounts of consciousness/brain causal interactions switch between first- and third-person perspectives. However, epistemically, the differences between first- and third-person access are fundamental. First- and third-person accounts (...) are complementary and mutually irreducible. (shrink)

This article summarizes a variety of current as well as previous research in support of a new theory of consciousness. Evidence has been steadily accumulating that information about a stimulus complex is distributed to many neuronal populations dispersed throughout the brain and is represented by the departure from randomness of the temporal pattern of neural discharges within these large ensembles. Zero phase lag synchronization occurs between discharges of neurons in different brain regions and is enhanced by presentation of stimuli. This (...) evidence further suggests that spatiotemporal patterns of coherence, which have been identified by spatial principal component analysis, may encode a multidimensional representation of a present or past event. How such distributed information is integrated into a holistic percept constitutes the binding problem. How a percept defined by a spatial distribution of nonrandomness can be subjectively experienced constitutes the problem of consciousness. Explanations based on a discrete connectionistic network cannot be reconciled with the relevant facts. Evidence is presented herein of invariant features of brain electrical activity found to change reversibly with loss and return of consciousness in a study of 176 patients anesthetized during surgical procedures. A review of relevant research areas, as well as the anesthesia data, leads to a postulation that consciousness is a property of quantumlike processes, within a brain field resonating within a core of structures, which may be the neural substrate of consciousness. This core includes regions of the prefrontal cortex, the frontal cortex, the pre- and paracentral cortex, thalamus, limbic system, and basal ganglia. (shrink)

*[[This paper appears in _Toward a Science of Consciousness II: The Second Tucson Discussions and Debates_ (S. Hameroff, A. Kaszniak, and A.Scott, eds), published with MIT Press in 1998. It is a transcript of my talk at the second Tucson conference in April 1996, lightly edited to include the contents of overheads and to exclude some diversions with a consciousness meter. A more in-depth argument for some of the claims in this paper can be found in Chapter 6 of my (...) book _The Conscious Mind_ (Chalmers, 1996). ]]. (shrink)

Can theories of mental imagery, conscious mental contents, developed within cognitive science throw light on the obscure (but culturally very significant) concept of imagination? Three extant views of mental imagery are considered: quasi‐pictorial, description, and perceptual activity theories. The first two face serious theoretical and empirical difficulties. The third is (for historically contingent reasons) little known, theoretically underdeveloped, and empirically untried, but has real explanatory potential. It rejects the “traditional” symbolic computational view of mental contents, but is compatible with recentsituated (...) cognition and active visionapproaches in robotics. This theory is developed and elucidated. Three related key aspects of imagination (non‐discursiveness, creativity, and seeing as) raise difficulties for the other theories. Perceptual activity theory presents imagery as non‐discursive and relates it closely to seeing as. It is thus well placed to be the basis for a general theory of imagination and its role in creative thought. (shrink)

This article presents a novel challenge to epistemic internalism. The challenge rests on a set of cases which feature subjects forming beliefs under conditions of “bad ideology”—that is, conditions in which pervasively false beliefs have the function of sustaining, and are sustained by, systems of social oppression. In such cases, the article suggests, the externalistic view that justification is in part a matter of worldly relations, rather than the internalistic view that justification is solely a matter of how things stand (...) from the agent’s individual perspective, becomes the more intuitively attractive theory. But these “bad ideology” cases do not merely yield intuitive verdicts that favor externalism over internalism. These cases are, moreover, analogous to precisely those canonical cases widely taken to be counterexamples to externalism: cases featuring brains-in-vats, clairvoyants, and dogmatists. That is, such “bad ideology” cases are, in all relevant respects, just like cases that are thought to count against externalism—except that they intuitively favor externalism. This, the author argues, is a serious worry for internalism. What is more, it bears on the debate over whether externalism is a genuinely “normative” epistemology. (shrink)

I. The Mind-Body Problem after Kripke This essay will explore an approach to the mind-body problem that is distinct both from dualism and from the sort of conceptual reduction of the mental to the physical that proceeds via causal behaviorist or functionalist analysis of mental concepts. The essential element of the approach is that it takes the subjective phenomenological features of conscious experience to be perfectly real and not reducible to anything else--but nevertheless holds that their systematic relations to neurophysiology (...) are not contingent but necessary. (shrink)

Um dos grandes desafios da era da informação consiste em filtrar informações claras, rigorosas e atualizadas sobre tópicos importantes. O mesmo vale para a filosofia. Como encontrar conteúdo filosófico confiável em meio a milhares de artigos publicados diariamente na internet? Para ir ainda mais longe, como encontrar uma introdução a algum tópico com uma lista de referências bibliográficas atualizadas e que seja organizada por um especialista da área? Já que você começou a ler este livro, é provável que tenha ouvido (...) falar em algum momento da Enciclopédia Stanford de Filosofia, disponível gratuitamente na internet desde 1995. A página da Stanford faz exatamente isso. Ela cobre inúmeros verbetes sobre quase tudo em filosofia, oferecendo informação confiável sobre temas como feminismo, filosofia na América Latina, zumbis, metafísica e milhares de outros tópicos. A sugestão típica aos profissionais da filosofia que têm interesse em começar a estudar algum tópico, mas não sabem sequer por onde começar, é procurar pelo verbete relevante da Stanford. Infelizmente, o grande empecilho da página para o nosso contexto é que todos os verbetes estão disponíveis apenas em inglês, algo que cria um obstáculo a inúmeros estudantes e interessados que não dominam a língua. Neste sentido, acreditamos que esta publicação preencha um hiato importante na filosofia brasileira. Embora a filosofia no Brasil tenha se profissionalizado e expandido ao longo dos anos, há ainda lacunas em diversas áreas, e os verbetes foram aqui selecionados cuidadosamente no intuito de preencher ao menos algumas dessas lacunas. Este livro apresenta quatro verbetes cruciais para a filosofia, aqui divididos em quatro capítulos: (1) condições necessárias e suficientes, (2) referência (3) causação e (4) consciência. (shrink)

In discussion on consciousness and the hard problem, there is an unquestioned background assumption, namely, our experience is stored in the brain. Yet Bergson argued that this very question, “Is experience stored in the brain?” is the critical issue in the problem of consciousness. His examination of then-current memory research led him, save for motor or procedural memory, to a “no” answer. Others, for example Sheldrake, have continued this negative assessment of the research findings. So, has this assumption actually been (...) proven since Bergson? Do we know how experience is stored? Or that it is stored? Here, a recent review and model of memory is examined to see where this assumption actually stands. Again, the assessment will be that nothing has changed. The core of the problem, it will be argued, lies in two things: Firstly, the search for how/where experience is stored is motivated—rephrasing Bergson—in the classic metaphysic, a framework on space and time whose logic cannot be coherently, logically adhered to in attempting to explain how experience is stored. Secondly, the search generally assumes an inadequate theory of perception that is implicitly based in this classic metaphysic. If framed within Bergson’s model of perception and his temporal metaphysic, conjoined with J. J. Gibson’s model, the storage-search appears misguided from the start. (shrink)

What is the primary function of consciousness in the nervous system? The answer to this question remains enigmatic, not so much because of a lack of relevant data, but because of the lack of a conceptual framework with which to interpret the data. To this end, we have developed Passive Frame Theory, an internally coherent framework that, from an action-based perspective, synthesizes empirically supported hypotheses from diverse fields of investigation. The theory proposes that the primary function of consciousness is well-circumscribed, (...) serving the 'somatic nervous system[. For this system, consciousness serves as a frame that constrains and directs skeletal muscle output, thereby yielding adaptive behavior. The mechanism by which consciousness achieves this is more counterintuitive, passive, and “low level” than the kinds of functions that theorists have previously attributed to consciousness. Passive frame theory begins to illuminate (a) what consciousness contributes to nervous function, (b) how consciousness achieves this function, and (c) the neuroanatomical substrates of conscious processes. Our untraditional, action-based perspective focuses on olfaction instead of on vision and is 'descriptive' (describing the products of nature as they evolved to be) rather than 'normative' (construing processes in terms of how they should function). Passive frame theory begins to isolate the neuroanatomical, cognitive-mechanistic, and representational (e.g., conscious contents) processes associated with consciousness. (shrink)

This introductory chapter attempts to clarify the philosophical, empirical, and theoretical bases on which a cognitive neuroscience approach to consciousness can be founded. We isolate three major empirical observations that any theory of consciousness should incorporate, namely (1) a considerable amount of processing is possible without consciousness, (2) attention is a prerequisite of consciousness, and (3) consciousness is required for some specific cognitive tasks, including those that require durable information maintenance, novel combinations of operations, or the spontaneous generation of intentional (...) behavior. We then propose a theoretical framework that synthesizes those facts: the hypothesis of a global neuronal workspace. This framework postulates that, at any given time, many modular cerebral networks are active in parallel and process information in an unconscious manner. An information becomes conscious, however, if the neural population that represents it is mobilized by top-down attentional amplification into a brain-scale state of coherent activity that involves many neurons distributed throughout the brain. The long-distance connectivity of these `workspace neurons' can, when they are active for a minimal duration, make the information available to a variety of processes including perceptual categorization, long-term memorization, evaluation, and intentional action. We postulate that this global availability of information through the workspace is what we subjectively experience as a conscious state. A complete theory of consciousness should explain why some cognitive and cerebral representations can be permanently or temporarily inaccessible to consciousness, what is the range of possible conscious contents, how they map onto specific cerebral circuits, and whether a generic neuronal mechanism underlies all of them. We confront the workspace model with those issues and identify novel experimental predictions. Neurophysiological, anatomical, and brain-imaging data strongly argue for a major role of prefrontal cortex, anterior cingulate, and the areas that connect to them, in creating the postulated brain-scale workspace. (shrink)

The 'non-sensory' feelings of familiarity, rightness and tip-of-the-tongue postulated in the target article all find a natural explanation within existing models, including Gray's comparator model, of the way in which top-down and bottom-up processing interact to select the contents of consciousness.

The "relational mind" approach to the inner content of consciousness is developed in terms of various control structures and processing strategies and their possible neurobiological identifications in brain sites. This leads naturally to a division of consciousness into a passive and an active part. A global control structure for the "single strand" aspect of consciousness is proposed as the thalamo-nucleus reticularis thalami-cortex coupled system, which is related to experimental data on the electrical stimulation of awareness. Local control, in terms of (...) excitatory transfer from pre-processing sites to posterior working memory regions, is supported by data on subliminal perception timing and disambiguation of poorly defined percepts. The inner content of consciousness is understood as arising from the resulting relational features between inputs and stored pre-processing and episodic memories. Strong analogies are drawn between emergent properties of the model and suggested properties of "raw feels", supporting the thesis that working memories are the initial sites for the emergence of phenomenal awareness, and the frontal lobes for its further adumbration in terms of higher cognitive processing, including the creation of self. (shrink)

This essay discusses some central philosophical problems concerning the naturalistic concept of consciousness, as well as evidence from neuropsychology and neurophysiology regarding the relation of brain activity and conscious experience. Initially I review the problem of defining "consciousness", the philosophical approach to the phenomenon and its relation to emotional processes. The next step is a proposal of three conditions for the attribution of consciousness to physical systems. In the following section, I identify different modalities of consciousness and their respective neural (...) correlates in different spatial and temporal scales. Finally, I discuss possible biophysical mechanisms underlying conscious processing.Abordo neste trabalho alguns dos principais problemas filosóficos concernentes a uma concepção naturalista da consciência humana, assim como algumas evidências disponíveis na neuropsicologia e neurofisiologia, sobre a relação entre atividade cerebral e experiência consciente. Inicialmente faço uma revisão sobre a definição de "consciência", seu estatuto filosófico e relação com os processos emocionais, e proponho três condições para sua atribuição a um sistema físico. Em seguida, identifico diferentes modalidades de consciência, e seus correlatos cerebrais em diferentes escalas espaciais e temporais. Finalmente, discuto possíveis mecanismos biofísicos subjacentes aos processos conscientes. (shrink)

Can one be fooled into believing that one intended an action that one in fact did not intend? Past experimental paradigms have demonstrated that participants, when provided with false perceptual feedback about their actions, can be fooled into misperceiving the nature of their intended motor act. However, because veridical proprioceptive/perceptual feedback limits the extent to which participants can be fooled, few studies have been able to answer our question and induce the illusion to intend. In a novel paradigm addressing this (...) question, participants were instructed to move a line on the computer screen by use of a phony brain–computer interface. Line movements were actually controlled by computer program. Demonstrating the illusion to intend, participants reported more intentions to move the line when it moved frequently than when it moved infrequently. Consistent with ideomotor theory, the finding illuminates the intimate liaisons among ideomotor processing, the sense of agency, and action production. (shrink)

In his novel Remembrance of Things Past, Marcel Proust argues that conventional descriptions of the phenomenology of consciousness are incomplete because they focus too much on the highly-salient sensory information that dominates each moment of awareness and ignore the network of associations that lies in the background. In this paper, I explicate Proust’s theory of conscious experience and show how it leads him directly to a theory of aesthetic perception. Proust’s division of awareness into two components roughly corresponds to William (...) James’ division of the stream of thought into a “nucleus” and “fringe.” Proust argues that the function of art is to evoke the underlying associative network indirectly in the mind of the observer by using carefully chosen sensory surfaces to control the stream of thought. I propose a possible neural basis for this Proustian/Jamesian phenomenology, and argue that the general principles of Proustian aesthetics can be applied to all forms of art. I conclude that a scientific theory of art should follow in a straightforward manner from a scientific theory of consciousness. (shrink)

Temporal binding via 40-Hz synchronization of neuronal discharges in sensory cortices has been hypothesized to be a necessary condition for the rapid selection of perceptually relevant information for further processing in working memory. Binocular rivalry experiments have shown that late stage visual processing associated with the recognition of a stimulus object is highly correlated with discharge rates in inferotemporal cortex. The hippocampus is the primary recipient of inferotemporal outputs and is known to be the substrate for the consolidation of working (...) memories to long-term, episodic memories. The prefrontal cortex, on the other hand, is widely thought to mediate working memory processes, per se. This article reviews accumulated evidence for the role of a subcortical matrix in linking frontal and hippocampal systems to select and ''stream'' conscious episodes across time (hundreds of milliseconds to several seconds). ''Streaming'' is hypothesized to be mediated by the selective gating of reentrant flows of information between these cortical systems and the subcortical matrix. The physiological mechanism proposed for this temporally extended form of binding is synchronous oscillations in the slower EEG spectrum (< 8 Hz). (shrink)

Imbalanced plasticity of neural networks in the brain is proposed to underlie deficits in the integration of efferent and afferent processes in schizophrenia. These deficits affect the priming of the behavior implementing systems by prior knowledge, and thus impair both controlled regulation and automatic activation of mental and motor processes. The sense of self as a distinct entity can consequently be undermined. In predominantly reality-distorting patients, hypo-plasticity of neural connectivity may cause the emergence of highly focused but inflexible patterns of (...) activation in their representation and response systems. This may lead to dominance of prepotent patterns of activity in these systems and a relative inability of higher control systems to bias lower level activity towards congruence with the ongoing cognitive and motor context. By contrast, predominantly disorganized patients are characterized by hyper-plastic connectivity. This leads to a weakening of prepotent response tendencies but also, as in reality-distorting patients, to less effective top-down contextual constraining. (shrink)

Neurobiological and cognitive models of unconscious information processing suggest that subconscious threat detection can lead to cognitive misinterpretations and false alarms, while conscious processing is assumed to be perceptually and conceptually accurate and unambiguous. Furthermore, clinical theories suggest that pathological anxiety results from a crude preattentive warning system predominating over more sophisticated and controlled modes of processing. We investigated the hypothesis that subconscious detection of threat in a cognitive task is reflected by enhanced ''false signal'' detection rather than by selectively (...) enhanced discrimination of threat items in 30 patients with panic disorder and 30 healthy controls. We presented a tachistoscopic word-nonword discrimination task and a subsequent recognition task and analyzed the data by means of process-dissociation procedures. In line with our expectations, subjects of both groups showed more false signal detection to threat than to neutral stimuli as indicated by an enhanced response bias, whereas indices of discriminative sensitivity did not show this effect. In addition, patients with panic disorder showed a generally enhanced response bias in comparison to healthy controls. They also seemed to have processed the stimuli less elaborately and less differentially. Results are consistent with the assumption that subconscious threat detection can lead to misrepresentations of stimulus significance and that pathological anxiety is characterized by a hyperactive preattentive alarm system that is insufficiently controlled by higher cognitive processes. (shrink)

Science is always presupposing some basic concepts that are held to be useful. These absolute presuppositions (Collingwood) are rarely debated and form the framework for what has been termed paradigm by Kuhn. Our currently accepted scientific model is predicated on a set of presuppositions that have difficulty accommodating holistic structures and relationships and are not geared towards incorporating non-local correlations. Since the theoretical models we hold also determine what we perceive and take as scientifically viable, it is important to look (...) for an alternative model that can deal with holistic relationships. One approach is to generalise algebraic quantum theory, which is an inherently holistic framework, into a generic model. Relaxing some restrictions and definitions from quantum theory proper yields an axiomatic framework that can be applied to any type of system. Most importantly, it keeps the core of the quantum theoretical formalism. It is capable of handling complementary observables, i.e. descriptors which are non-commuting, incompatible and yet collectively required to fully describe certain situations. It also predicts a generalised form of non-local correlations that in quantum theory are known as entanglement. This generalised version is not quantum entanglement but an analogue form of holistic, non-local connectedness of elements within systems, predicted to occur whenever elements within systems are described by observables which are complementary to the description of the whole system. While a considerable body of circumstantial evidence supports the plausibility of the model, we are not yet in a position to use it for clear cut predictions that could be experimentally falsified. The series of papers offered in this special issue are the beginning of what we hope will become a rich scientific debate. (shrink)

Two aspects of consciousness are first considered: consciousness as awareness (phenomenological meaning) and consciousness as strategic control (functional meaning). As to awareness, three types can be distinguished: first, awareness as the phenomenal experiences of objects and events; second, awareness as meta-awareness, i.e., the awareness of mental life itself; third, awareness as self-awareness, i.e., the awareness of being oneself. While phenomenal experience and self-awareness are usually present during dreaming (even if many modifications are possible), meta-awareness is usually absent (apart from some (...) particular experiences of self-reflectiveness) with the major exception of lucid dreaming. Consciousness as strategic control may also be present in dreams. The functioning of consciousness is then analyzed, following a cognitive model of dream production. In such a model, the dream is supposed to be the product of the interaction of three components: (a) the bottom-up activation of mnemonic elements coming from LTM systems, (b) interpretative and elaborative top-down processes, and (c) monitoring of phenomenal experience. A feedback circulation is activated among the components, where the top-down interpretative organization and the conscious monitoring of the oneiric scene elicitates other mnemonic contents, according to the requirements of the dream plot. This dream productive activity is submitted to unconscious and conscious processes. (shrink)

Most scientists and theorists concerned with the problem of consciousness focus on our consciousness of the physical world (our sensations, feelings, and awareness). In this paper I consider our consciousness of the mental world (our thoughts about thoughts, intentions, wishes, and emotions).The argument is made that these are two distinct forms of consciousness, the evidence for this deriving from studies of autism. Autism is a severe childhood psychiatric condition in which individuals may be conscious of the physical world but not (...) of the mental world. Relevant experimental evidence is described, including some recent neuroimaging studies pointing towards the neural basis of our consciousness of the mental. (shrink)

Conscious awareness of intentionality is considered to be a product of specialized monitoring processes which distinguish intentional, goal-directed actions from unintentional, passive/ reactive actions. When goals are not met or unfavourable conditions arise, this ability to distinguish intentional and unintentional enables us to direct adaptive efforts towards either changing plans and goals or towards altering the environment. The formulation is discussed in relation to monitoring theories of consciousness and the concept of 'locus of control', and is developed to explain several (...) common psychological disorders in terms of dysfunctional monitoring of intentions. It is suggested that it could provide a theoretical basis for psychological treatment methods. (shrink)

Velmans (1991a; 1991b) proposed that consciousness plays a minor explanatory role in the information processing approach and that unconscious mechanisms process stimuli and responses and intervene between them. In contrast, the present commentary describes a thought experiment suggesting that, although input information is initially processed unconsciously, subsequent processing involves consciousness, and consciousness plays an important role in the explanation of behavior.

Conscious events interact with memory systems in learning, rehearsal and retrieval (Ebbinghaus 1885/1964; Tulving 1985). Here we present hypotheses that arise from the IDA computional model (Franklin,Kelemen and McCauley 1998; Franklin 2001b) of global workspace theory (Baars 1988, 2002). Our primary tool for this exploration is a flexible cognitive cycle employed by the IDA computational model and hypothesized to be a basic element of human cognitive processing. Since cognitive cycles are hypothesized to occur five to tentimes a second and include (...) interaction between conscious contents and several of the memory systems, they provide the means for an exceptionally fine-grained analysis of various cognitive tasks. We apply this tool to the small effect size of subliminal learning compared to supraliminal learning, to process dissociation, to implicit learning, to recognition vs. recall, and to the availability heuristic in recall. The IDA model elucidates the role of consciousness in the updating of perceptual memory, transient episodic memory, and procedural memory. In most cases, memory is hypothesized to interact with conscious events for its normal functioning. The methodology of the paper is unusual in that the hypotheses and explanations presented are derived from an empirically based, but broad and qualitative computational model of human cognition. (shrink)

Twentieth century philosophy and psychology have been peculiarly averse to mental images. Throughout nearly two and a half millennia of philosophical wrangling, from Aristotle to Hume to Bergson, images (perceptual and quasi-perceptual experiences), sometimes under the alias of "ideas", were almost universally considered to be both the prime contents of consciousness, and the vehicles of cognition. The founding fathers of experimental psychology saw no reason to dissent from this view, it was commonsensical, and true to the lived experience of conscious (...) thinking. However, early in this century, just about when the behaviorist revolution in psychology was loudly declaring the scientific illegitimacy of any attempt to study consciousness, and the concomitant non-existence of imagery (Watson, 1913; see Thomas, 1989), philosophy was undergoing its "linguistic turn", a turn to seeing philosophy as essentially about language rather than the world, even the 'inner' world. For decades, the very concept of the mental image was suspect, and it was certainly banished from playing any major role in theories of mind and of thinking. Ralph Ellis' Questioning Consciousness, together with the recent speculations of certain influential neuroscientists (Edelman, 1992; Damasio, 1994), may be signaling the end this unusual era. (shrink)

People acquire new beliefs in various ways. One of the most important of these is that new beliefs are acquired as a response to experiencing events that one did not expect. This involves a form of inference distinct from both deductive and inductive inference: abductive inference. The concept of abduction is due to the American pragmatist philosopher C. S. Peirce. Davies and Coltheart elucidated what Peirce meant by abduction, and identified two problems in his otherwise promising account requiring solution if (...) that account were to become fully workable. Here we propose solutions to these problems and offer an explicit cognitive model of how people derive new beliefs from observations of unexpected events, based on Peirce's work and Sokolov's ideas about prediction error triggering new beliefs. We consider that this model casts light not only upon normal processes of belief formation but also upon the formation of delusional beliefs. (shrink)